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View Full Version : Definitiely something wrong.Car is running hot.



kameraguy
09-26-2003, 08:29 AM
I had my coolant changed (flushed?) by the dealership about three months ago. I am not sure if they "flushed" it, but I assume they do this for any coolant change?

Anyway, about two months afterwards i notice my car running warmer than usual. For my car, it usually runs around 80-85 degrees, even after a long or hard drive.

But nowadays it hovers in the 90-97 degree range.

Being concerned, I added some Redline Water Wetter to the existing coolant, but this did not seem to make a diff.

So now the last few days, I notice my engine fan kicking in more often nowadays.

Also, right after the first start of the day, my engine warms up to around 87 degrees not even after 5 minutes of driving.

I was wondering if anyone has had similar experience, and any ideas of how to correct this? Coolant change? Thermostat? Radiator?

I know this is supposed to be in the "typical" operating parameters per Mercedes Benz, but we all know how our cars are "supposed" to run, so any change in behaviour is easily seen by the owner.

Any thoughts, ideas is greatly appreciated.

Denlasoul
09-26-2003, 08:47 AM
Kam:

My car runs between 80-90 degrees depending on the outside temp. If you are hovering around the 90 mark, and previously hovered around 80~ish, then I would check my thermostat.

Good luck. I'll try and dig up more info.

DLS

jnolte
09-26-2003, 09:31 AM
My car usually runs around 80-85 degree temps. BUt thwn i have been driving all day or under hot conditions it goes up to 90 sometimes.

kameraguy
09-26-2003, 09:56 AM
Thanks for the feedback guys. I know what you mean. My car used to be the same way!

I never exceeded 90 degrees, even on the hottest summer day while driving my car hard. So I know something is wrong as now i'm barely driving the thing and it's already past 90 degrees.

DLS, if you find any more info that may help me, i'd appreciate it. Thanks for looking.

So when you say thermostat.... meaning this can be faulty and my engine is not that hot, or would that affect how my engine runs (making it run warmer)?

I'm going to set up an appointment with the dealer to have them look at this too. I just hate going there as they have you pay up front just for a look. Maybe they'll be cool and at least have a quick look without hassle :(

Rocky
09-26-2003, 10:04 AM
A thermostat is cheap enough that you should just try and replace it yourself with an OEM one.

Does your temp move wildly? like up and down 5-10 degrees when driving? Does hot hot air come out with 'HI'?

It happened to me..change the thermostat and no problems.

ruffino28
09-26-2003, 10:10 AM
i got pretty much like the same problem as you but more worst mine run between 90- 110 degrees (in local) sometime even more and below 80 (highway)
i had them (dealer) checked that already but they didnt say anything they just changed the coolant hope u guys can find something

kameraguy
09-26-2003, 10:27 AM
Rocky, for my problem the temp doesn't fluctuate wildly, unlike my fuel guage....stoopid fuel guage...I HATE you!!!

But i digress, the temperature guage seems to behave normally....gradually picking up temp, or slightly reducing on occasion (probably due to the fan kicking in).

Is the Thermostat easy to swap? And how much do they usually run? Maybe i'll try this if it's easy enough.

I'll try to blow hot air from the climate control when my car is running hot to see if the air is warm, and if it reduces the engine temperature too....

kameraguy
09-26-2003, 10:28 AM
Ruffino,

What car and how many miles do you have?

And how long has this been an issue for you. 110...geez, that's up there!!!

Has that ALWAYS been a problem, or just recently?

ruffino28
09-26-2003, 10:37 AM
kam
been long time already
mine 95 c280 34000~ miles
sometimes when engine temp up to 110 then i have to turn on the heat and its help to drop the temp

kameraguy
09-26-2003, 10:44 AM
WOW! a 95 with only 34K?! Impressive!

So have you had this problem looked at Ruffino? It seems your problem is worse than mine....and i'm already stressed!!

Are there any problems with a MB running this hot? Or is this still truly within "normal" operating specs?

ruffino28
09-26-2003, 11:04 AM
i had them (dealer) checked that already 2 weeks ago but they didnt say anything they just changed the coolant

do u guys think this might help http://www.performanceproducts.com/ProductPage.aspx?productname=Exhaust+Insulating+Wr ap+by+Cool+It&productid=109473&producttype=10

kameraguy
09-26-2003, 11:17 AM
So the dealer changed your coolant 2 weeks ago?

Did this help any? Any difference at all?

I don't think running over 100 degrees is normal. It would be odd the dealer didn't find anything wrong, especially if your car ran cooler in the past.


I think that accessory in performance parts is going to mask what the true problem is, if it's an external heat issue. But if it's in internal problem, i doubt that would make a diff.

Plus, if you never had this issue before, that accerssory is only going to hide the fact something is still wrong :(

Denlasoul
09-26-2003, 11:28 AM
I got some info from the old B*nzsport site that I just happened to print out. I'll post it up when I get home.

DLS

kameraguy
09-26-2003, 11:30 AM
Thanks DLS, I appreciate the legwork!!! :D

Renn 208
09-26-2003, 12:09 PM
Originally posted by Denlasoul
I got some info from the old B*nzsport site that I just happened to print out. I'll post it up when I get home.

DLS

Is Benzsport a bad word or something? I miss that great ol site.

kameraguy
09-26-2003, 12:21 PM
So it appears from the poll there are already four of us who run at least 90 degrees consistently.

So for those that are hovering at or over 90, do you find this a problem?

This is my first experience with it, so i don;t know if this is a warning sign of problems manifesting, or me just being paranoid, and the car will be ok.


I am hoping it's the latter.

Rocky
09-26-2003, 01:05 PM
Originally posted by kameraguy
WOW! a 95 with only 34K?! Impressive!

So have you had this problem looked at Ruffino? It seems your problem is worse than mine....and i'm already stressed!!

Are there any problems with a MB running this hot? Or is this still truly within "normal" operating specs?

My uncle has a 2000 C230 with 2600 km on it.

the themostat is just as easy as the MAS..make sure when you take out the original you know where the hole is facing.

30 dolller part?

Renn 208
09-26-2003, 01:13 PM
I wont answer the poll to keep the results clean, but as I've stated before:

Right at 83C anytime I can cruise at highway speed, and close to 100C when stuck in traffic, or driving through SF. And when I turn on the defroster under stress conditions I can get it to drop to 86C...been that way ever since I got the car.

Rocky
09-26-2003, 01:18 PM
Celsius people....everyone else uses celsius hehehehe

kameraguy
09-26-2003, 01:59 PM
Originally posted by Renn 208
I wont answer the poll to keep the results clean, but as I've stated before:

Right at 83C anytime I can cruise at highway speed, and close to 100C when stuck in traffic, or driving through SF. And when I turn on the defroster under stress conditions I can get it to drop to 86C...been that way ever since I got the car.

Renn, I appreciate the input. I must have missed the last time you posted this so sorry if you have to repeat yourself yet again.

I'm specifically interested in a w202. But does this type of issue hold true for any MB, including a CLK?

To me, this does NOT seem normal.

But I guess other people live with it fine???

Can ya tell i'm freaking out about this? My baby has a fever :(

Denlasoul
09-26-2003, 02:09 PM
Kam:

This was a post from the Ol Benzsport site:

"...I assume you mean stop-and-go traffic. If this is the case, it is most likely your fan cluch. That is why it is overheating when you stop! One easy way to find out if it is your fan cluch:
1. Turn on your car and let the temp rise up a little (be careful you dont overheat the engine).
2. Wiht the car on and parked, open the hood and look at the fan cluch. It should be spinning.
3. Turn off the car while looking at the fan cluch. If after turning off the car, the fan keeps on spinning, your fan cluch is messed up. However, if it stops when you turn off the car, then you are safe.
I would do this first, if the fan cluch is ok, then your next possibilities are thermostat, coolant tank and tap, radiator, and water pump. Hope this helps...."

-Inky Winky from Benzsport

I would suggest you do the same, Kam. If the fan cluch is good, I would just go down the list "IW" provided.

Good luck,

DLS

Renn 208
09-26-2003, 02:37 PM
Hmm, I think I need that explained to me. Why, if the fan keeps spinning, would this cause an overheating condition? Granted, I can take it at face value that is how to check if the clutch is broken, but it's the overheating part that I don't quite get.

kameraguy
09-26-2003, 02:45 PM
I'll certainly check this out....but I'm with renn on this one. I figure if the fan isn't spinning, now that's the problem.

Of maybe what IW was getting at was the fan isn't reliably spinning at the required rate...as it's slipping? So possibly it's not spinning as fast as it needs, or irregularly? Hmmmmm...

Well, i'll have a look-see. I seem to recall hearing the fan wind down more noticeably after turning off the car...I never noticed that before. Maybe that means the fan is still spinning.

I'll let you guys know. Thanks for all of your help :)

Recaro18
09-26-2003, 03:11 PM
95 C280 w/ 60k miles, its been running hot ever since i got the car...replaced the fan clutch, the thermostat (low temp rating so the fan kicks on earlier) and coolant flush.....same thing...driving to sacramento at 100 degrees, my temp goes up as high as 110 degrees on stop and goes back down to 100 on the highway...i was the same way as you before, but i guess i got used to it...

i've called MB about this problem, and they said its normal....but if you can find a way to lower the temp on your car, tell me so i can try on mine too....

kameraguy
09-26-2003, 03:14 PM
It seems MB always states this is "normal". Wierd.

I distinctly remember my car not running this hot until very recently. Something must have changed or gone bad. Just doesn't make sense to have a car working much cooler prior, then to change as drastically as 15 degrees.

Making an appointment with the dealership now....

ruffino28
09-26-2003, 04:05 PM
the temp problem is really annoying but i think i got used to it already actually i dont use the car much so...
i talked to 2 diff mb dealer mechanic they said normal
kam hope ur dealer fix ur problem

202rules
09-26-2003, 05:07 PM
I sort of got worried about this in the past too. But I have to say cars will run hot in certain conditions, which IS normal, as long as it doesn't redline. So if it's a really hot summer day, it's normal to run in the 100 even 110 if you have the air condition on. Slow traffic adds a lot to it coz you're not getting cooler air, you're getting the air from the exhausts of other cars in front of you (I noticed this at an automatic car wash once trust me). So I would only worry if it got really hot in normal conditions. My mechanic once told me too that the 95 C280s do get hot in there coz of the relatively big 6 inline.

So notice the conditions you're driving in. And it never hurts to run checks on the car.

marksbenz
09-26-2003, 05:31 PM
Yo Kam just to be on the safe side. Change the thermostat. Probably its not opening all the way. Mercedes cars seems to run hot. Mine goes up to 90 when driving in traffic. But goes back down. If your temp doesnt go down and keeps on going up, then you have a problem. I'll try changing the thermostat.

oaktownc43
09-26-2003, 08:41 PM
Hello...my 1999 C43 on a hot day in traffic goes up to 100C max..then when I get rolling on the freeway it goes down to approx 85C.
If your car didnt run as warm before the coolant change then it is possible that the previous mixture of water/antifreeze had more water in it then antifreeze thus allowing the engine to run cooler since water cools a engine better but doesnt have the protection of antifreeze. You can get a antifreeze checker or lithium stick to check your percentage of water/antifreeze.

Hope this helps
Phillip
1999 C43

Denlasoul
09-26-2003, 09:45 PM
Originally posted by kameraguy
I distinctly remember my car not running this hot until very recently. Something must have changed or gone bad. Just doesn't make sense to have a car working much cooler prior, then to change as drastically as 15 degrees.

I am with you on this one. I would think some parameter has changed and has caused the increase in temp. It makes sense.

edit: oaktown, I sent you an email, but not sure if you got it. I was having email problems. just tell me if you didnt get one, and I'll try to recall what I wrote.

kameraguy
09-27-2003, 09:12 PM
Well guys, guess what?!

http://kameraguy.8m.com/images/hot.jpg


Today my car decided to go all the way!

So after 1 hr of driving, with my car at 100degrees almost all the way, it decides to call it quits and go all the way to 120+ once i stopped at my destination :confused:

It was the most amazing thing. I see my temp needle at 100 once i stopped...then 105..107 (my eyebrow is now raised like the Rock), 115...and it kept going. Fans were whining as they have been in the recent past...full and loud!

Once it started to go past 120, I shut the engine off!!!!!!!! Man, I had a heart-attack I swear.

So, I check the engine. Fortunately it does not look like anything has boiled over.

So I wait about 15 minutes, and start the engine again. Still at 115.

Stop engine, and check the coolant. Looks full and the same as before. No loss of coolant or anything.

So i'm thinking what I should do. then I remember someone mentioned to check the oil too. So I did, thinking I wouldn't find anything odd cuz I just got an oil change about three months ago...

Guess what....I was at the bare minimum. Wierd!

So of course i'm speculating an oil leak, or maybe whoever worked on my car last didn't change it or f*cked with my car to cause this on purpose :mad:

But no sense in dwelling on what-ifs. So I found a Kragen and bought a few bottles of mobile one 10w-30 syn and brought the oil levels back to normal.

I was hoping this was the culprit. But unfortunately not. Once i got going again, the car got back up to 118.

So i called my mechanic and he said to bring it by. Thing is i'm like 1hr away from him. So I eventually coordinated a tow truck to the shop, which cost $680!! $10/mi...and I was 68 miles away :(

http://kameraguy.8m.com/images/towhooks.jpg

http://kameraguy.8m.com/images/flatbed.jpg

Fortunately I was also able to contact Joey and Mona, and their brother Richie, so they helped me and my parents (yup, I was not alone :( ) get to the shop safely and shuttle us back home, which was like another 70 miles from the shop. Man, they are the best. Thanks again guys. I'm really glad you were there and i'm real sorry to have thrown a wrench in your Saturday plans :(

So my car is now at Topline in Burlingame. I have faith my car is in good hands with Zim. I'm just a bit stressed and pissed of such a problem.

http://kameraguy.8m.com/images/topline.jpg

I am anxious to find out what the problem is, but I sure hope it's not related to something the dealership might have done (not done). I'll be sure to let you guys know what happens next.


So for now, I await an update as to what the culprit is. But if there's anything I can share with you guys....it is better be safe than sorry. if your car is running hot, better check it out and fix it before it gets worse!

It is still my standpoint anything above 100 degrees is a problem, and maybe your car isn't overheating like mine, but it's a possible sign of an existing problem that can eventually get worse :(

If MB says our cars are running "normally" above 100 degrees....BULLSHIT!!!

nokia8860
09-27-2003, 09:17 PM
Nice pics :confused: :p

Denlasoul
09-27-2003, 10:12 PM
DAMN! Something is definitely wrong! Your first pic is your temp running at 120 Degrees and yet the outside temp was 59?

Crap! Sorry yu wne through all this mess. I hope Zim gets to the bottom of the problem.

Big ups to Nokia, Mona, and brother? You guys all represent what Club202 and friendships are about.

Good luck

DLS

Rocky
09-27-2003, 10:38 PM
dang kam...hope thing work out.

*thermostat* hehehe 20-30 bucks *hint* *hint*

To test the thermostat, take it out..let it cool and boil it in water with a thermometer..see when it starts to open.

BTW, you using MB coolant or other stuff?

Not suppose to use non-mb coolant.

ruffino28
09-27-2003, 10:54 PM
wow... thats happened once on my car too in local long time ago almost reached 120 but it went down to 90 after got into highway and pressed on defroster ...
kam i totally agree with u "MB says our cars are running "normally" above 100 degrees....BULLSHIT!!!"

714guy
09-28-2003, 07:24 PM
sorry to hear about your car problems man, I am going thru the same the thing now.

Good lucj with things, keep us updated on the situation.

Thanks

CKlasse
09-28-2003, 08:59 PM
Sorry to hear that KAM... Hopefully TOPLINE can solve the issue ASAP. There are too many possibilities - Detonation might be your cause. Good luck to you.

kameraguy
09-29-2003, 08:59 AM
Thanks for the support guys. I know a lot of you are also having "normal" overheating issues, so i hope I can provide some insight once my car is fixed. I'd hate to have this happen to anyone else. It sucks. It might be a simple fix, but it can cause major headaches.

To anser some questions, yes I was using OEM coolant, but the engine still ran hot. It wasn't until very recently I added Water Wetter to try and help things but it really didn't make a diff, nether good or bad.

Other variable:
* Low Oil. At the bare minimum mark.

Well, i'll call up Zim this afternoon and see if he's had the chance to look at it yet.

I suppose I may as well have him change the oil too as it is almost time anyway.

And yup. Nokia, Monatheism, and his bro Richie were lifesavers. Awedsome friends to have :)

Brabus
09-29-2003, 10:06 AM
Dang Chris, sorry to hear... I know Zim will find the problem...

kameraguy
09-30-2003, 09:42 AM
Zim updated me end-of-day yesterday and said he hasn't found the problem yet. Said my car didn't overheat, but was running between 87 and 90 degrees consistently. Asked me if that was normal....to which i replied NOPE!!!

But he changed the thermostat and that didn't resolve anything.

I asked him to drive the car longer and harder, as i was cruising at 80mph when i notice dthe engine really get hot. So he said he would try that. He suggested he should drive the car home last night, which i replied was fine, as long as he didn't blow the engine or get stranded!!! :p

So hopefully i'll have an update with good data by this afternoon....

Rocky
09-30-2003, 09:48 AM
Hmm.very baffling.

Maybe the temp sensor itself is buggy just like the way some fuel gauges were?

Are your rad fans pushing air the right way? Do they come on?

moedigga
09-30-2003, 01:43 PM
I just drove home this weekend to MA, 80-90mph whole way 60-80 degrees and temp never went above 81-83 maybe. No a/c aswell. In mid summer when its 98 and I'm sittin in stop and go traffic with a/c on full temp will get to 90 even. Thats the hottest I've seen to date. Average temp is between 85-90.-MOE

kameraguy
09-30-2003, 02:08 PM
Moe, that's how i remember my car. Even while driven hard, it would barely break 85 degrees, even on a hot summer day. And in fact I never even hit 90...nor 87.

So I know there's a lot of inconsistency with how all our cars run. But once you see another 202 running closer to 80-85 degrees at most, it's hard to consider anything hotter "normal".

Well, still waiting for an update.....

nokia8860
09-30-2003, 02:20 PM
grrrr

CKlasse
09-30-2003, 06:05 PM
KAM..if you leave your car at idle constantly, 85-90C is normal. If Zim happened to drive it around all day, it should be between 80-85C.

BTW.. many C280s have faulty temp sensors. I dont know about C36, but this is something you should really look at.

oaktownc43
09-30-2003, 06:27 PM
I checked with the mercedesshop parts and the stock factory thermostat on a 1999 C43 is 87C so the tempature must at least reach that at a minimum for it to even open. My car will go to about 100C max on a hot day and I have been told by very good mercedes techs that this is ok and normal.It has never gotten higher than 100C at any time so far. At speed it will go to approx 88C a little above thermostat rating.
Phillip
1999 C43

kameraguy
09-30-2003, 07:20 PM
Ok, so Zim called me back and said my thermostat was indeed messed up. In a bucket of warm/hot water, it did not open up. So that may explain part of the issue.

I say PART because it appears my car is still running a bit warm. He drove it home and back to the shop and the car did not overheat with the new thermostat per-se, but my car was still around 90 degrees, even while driving.

Now I suppose 85 degrees is "normal" when the car is idling...but i figure if you are driving, especially on a cool day, the car should drop between 80 and 85. According to Zim it did not. It remained around 87-90 degrees.

So, he said he will look at the temperature sensor and see if that is good.

It seems you guys are right where he is regarding the temp sensors. So i hope those check out faulty or something. I'd rather know there was a problem with some component than have a "gremlin" issue, you know?

If this issue is indeed a faulty sensor, I will feel much better. I just don't want to take the chance the car really is that hot and overheat the engine!

Thanks again guys for the help and support. I really appreciate the insight and advice :)

CKlasse
10-01-2003, 07:32 AM
Perhaps a quick tune up is in order Kam...

Clean Injectors - RC ENGINEERING STYLE
Clean fuel Rail
Ignition tune up (yours DIS right?)
BG Oil Cleaner, and BG Vavle Cleaner....

will bring your car back to factory specs! Total cost to do it yourself is less than a large bill. This is a good chance to do write up! :D

In any case..good to know that your car is back!

kameraguy
10-01-2003, 08:08 AM
Thanks for the info cklasse. Actually i don't have my car back yet, but i'll consider these things once I do get it back :)

kameraguy
10-02-2003, 03:51 PM
Ok guys, I picked up my car and so far a bit better.

Ok...no more redzone, so it's all better now :p

But it's still not as "cool" as how I remember it.

So I think the problem is 90% fixed...with a bit that still needs to be sorted out....


Question for you guys with C36's....

What is your "normal" engine temperatures for the following situations:

1) idle after warm-up, first start of the day.

2) idle after the end of the day

3) consistent cruising on the freeway

4) stop and go traffic

Here's mine (after getting my car back with replaced T-Stat and change-oil):

1) 82 degrees

2) 83-84 degrees

3) 84-82 degrees

4) 85-90 degrees

I just want to know if this is consistent with other C36 owners. Maybe i'm beeing paranoid, or maybe my car is warmer than others.

I know Junaidi hardly has any heating issues...so I like to use his as a baseline of what is "normal" :p

Rocky
10-02-2003, 04:36 PM
Mine runs about the same as yous kamer.

davis449
10-02-2003, 06:05 PM
You guys convinced me, I'm taking mine to the dealer to get the thermostat looked at. This would be the third thermostat, counting the one that originally came with the it, that's been replaced on this car.

kameraguy
10-03-2003, 09:18 AM
So after some research it appears the OEM thermostat for a w202 is supposed to open only at approx 87 degrees.

So, if this is correct, shouldn't a w202 only run as hot as that before cooling down?

So maybe with this in mind, my car temps are ok (i'm still trying to reduce this further though), but for those running 95-100 or more....especially in "normal" driving situations...I still think this is not normal. Unless this indicates a w202 cooling system is not able to effectively cool the system. But since there are a few of us who don't see anything over 100...or even 90 for that matter....i'd still advice to have the car checked out.

Some things I found while researching this which may help someone who may not know already:

1) Coolant Cap....if it doesn't create a strong seal, the cooling system can't pressurize, so in essence you have a breach in the cooling system. Check that and replace if in doubt.

2) Make sure to use MB Antifreeze. Which i believe is also Zerex. Some MB owners report warmer temperatures unless using this stuff.

3) Ratio of coolant to water. The more water in the system, the more heat absorbing properties the system has. It seems this is one of the biggest variables which affects engine temps. So I suppose it depends on where you live, but make sure the ratio is correct. If in doubt, re-do it yourself. I believe there is a device to mesure the specific gravity of the coolant mixture to help determine if it is ideal or not.

4) Thermostat. My issue was defintely a bad t-stat. Seems to be an easy fix, so double check it.

5) Temperature sensor. Have this checked to see if it is functioning correctly.

6) Make sure you have EXACTLY the correct amount of coolant. Too little, or even too MUCH can cause cooling system issues. This must be exact for ideal operation. If you need to top-off, adding distilled water is preferred over more coolant as more water always helps with the cooling.

7) coolant color should be clear. i'm still confirming this, but I read online MB coolant is clear. If it's not, this is probably not MB coolant.

* if someone can confirm or correct me on this one i'd appreciate it.

8) Fan relay. Make sure your fans are working correctly. I reasd the ceramic sensor is also in a poor location which can easily be damaged. For example, a car wash may damage this sensor.

*if someone can confirm the location, i'd appreciate it. I read it was somewhere in the front bumper?

8) obviously check for any leaks.

9) fan belts. Make sure they are not loose or damaged.

10) fan clutch. Check to make sure this is indeed operating correctly.

11) Radiator. I suppose it stands to reason an older car with the OEM radiator loses it's ability to cool the engine over time. Whether it is a gradual issue which increases engine temp slowly over time, or if it is an abrupt change, i do not know. But I suppose in a worse case scenario this will need to be checked as well. With a car over 100K on the clock, might as well replace it and related hoses. It sure can't hurt and 100K is not a bad service life anyway. I will do this soon.



This is something i'm still looking into, but I hope the above may help others get an idea of what to look for if they have temperature issues. I'll add more info as i find it.

Edit: btw, I found some good info at mercedes shop related to engine temp issues. And i also found Duck Muck there. I guess that's where he is hanging out nowadays :p

Recaro18
10-03-2003, 09:29 AM
so Kam, what did Zim actually replace on your car? i get paranoid specially on hot weather...and guess what, i'm moving to sacramento, so i need to know a way to get my temp to go down....

thanks

Ricky

Renn 208
10-03-2003, 09:54 AM
MB coolant is clear, but not colorless, it's a super faint yellow, but is essentially clear when mixed in your coolant tank.

This is one of the ways that MB techs can tell if you've used anything other than MB Coolant. Put a drop of the green stuff in and you'll be flushing for days to get the green to disappear.

speedybenz
10-03-2003, 10:26 AM
On my C43 I use very little anti-freeze, about 1/2 gallon of Halvoline stuff and the rest is water and then watter wetter.

I would like to find a thermostat that opens at say 75 degree C but haven't had any luck finding one.

Kam, could you send me your old thermo so I can see if the are other models out that will have the same phyical dimensions but maybe a lower opening temp.

Jeff

kameraguy
10-03-2003, 11:32 AM
Ricky, Zim replaced my thermostat.

Jeff, i'll see if that thermostat is still in the shop. If not, i'll see if he can give me another broken t-stat for a w202.

I would definitely be interested in a cooler opening t-stat.

Are there any problems using a thermostat that opened at say 75 or 80 degrees? Would this also cause problems if the car ran between 80 and 75?

From what i'm seeing with my car, if it's true the t-stat opens at 87degrees, then this basically keeps my car hovering around 87 -91. So I suppose a t-stat which opens at 75-80 would theorhetically keep my car at 80-84-ish...

Would sound much better than how it is now.

Any reason MB chose to use 87 degrees?

Also, I wonder if these t-stats are not consistent, explaining why we have so many variances of "normal" operating temperatures.

kameraguy
10-03-2003, 11:40 AM
Originally posted by speedybenz
On my C43 I use very little anti-freeze, about 1/2 gallon of Halvoline stuff and the rest is water and then watter wetter.

I would like to find a thermostat that opens at say 75 degree C but haven't had any luck finding one.

Kam, could you send me your old thermo so I can see if the are other models out that will have the same phyical dimensions but maybe a lower opening temp.

Jeff

Jeff, with this mixture, is this applicable for the I6 cooling system?

Also, do you also experience engine temps above 85 on a regular basis? What has been the max sustained temp you've had during normal driving...not tracking :p

Renn...so your car runs over 100 degrees at times?!

kameraguy
10-03-2003, 11:51 AM
Originally posted by oaktownc43
I checked with the mercedesshop parts and the stock factory thermostat on a 1999 C43 is 87C so the tempature must at least reach that at a minimum for it to even open. My car will go to about 100C max on a hot day and I have been told by very good mercedes techs that this is ok and normal.It has never gotten higher than 100C at any time so far. At speed it will go to approx 88C a little above thermostat rating.
Phillip
1999 C43

My bad Philip, I overlooked the fact you already confirmed 87degrees is the t-stat open temp.

100 degrees or higher.....for some reason that doesn't sit right with me. Maybe because i've seen my needle go all the way to 120. So if I see my needle go past 100....then what's considered "not" normal?? like, is 118 still normal? That's pretty damn close to red.

Also, had I not been worrying about my engine after it past 100...I could have easily overlooked it going all the way...

This is definitely personal opinion, but i'm sure you guys already know how freaked I get over problems which i could avoid, and for me, I want that temp needle registering as close to the middle as possible. And i'm not talking about "fixing" the needle so it only registers 80! I mean I would love the peace of mind knowing my engine is as close to 80 as possible. 85-90 I suppsoe can't be helped due to the OEM t-stat. But anything higher just gets under my skin.

kameraguy
10-03-2003, 11:57 AM
Originally posted by Rocky
Mine runs about the same as yous kamer.

Thanks for the feedback Rocky. This makes me feel a bit better.

So is it not correct to want a cooler running engine, or is 90 degrees really just a fact of life.

But if we can find a way to reduce engine temps, that would be awesome. At the very least, there's gotta be a way to get those running around 100 or so even lower.

kameraguy
10-10-2003, 03:49 PM
Question:

Any problems running a W202 without a thermostat?

I understand the car will take longer to warm up without it. Would this be a problem in itself if the engine is running cold? More fuel consumption, higher emmisions, etc?

But once it is warm, is the thermostat needed?

Would this theoretically keep the engine cooler once the 87 degree restriction is bypassed?

Just a thought.

nokia8860
10-13-2003, 08:43 PM
Runing the part numbers you find that the thermostat 110 200 05 15 which opens at around 87C, I say around because there are +/- to it as its not that exact... hey its wax, the part is used for alot of different MB models. Which means then of course the selection in the aftermarket is alot more than just searching for a 93-00 202.

So basically if you lust for a 78C/174F thermosat then visit your local autoparts store and pick up a Beck/Arnley 1430578 for around 20 bucks. However, 78C might be a little to cold for most applications and you might be better off with Beck/Arnley 1430602 which opens up at 82C/180F.

Either way, if youre unhappy with your thermostat opening at 87C you do have other selections out there. Also keep in mind you can find other brands that make the replacement thermostat just ask the parts guy what are the cross part equiv of the ones mentioned above cuz maybe you like mr gasket, be cool, stants or whatever else.

Also make sure you change up your mixture with more water than coolant as this will help lower temps as well.

Recaro18
10-14-2003, 09:26 AM
cool joey, i'll try that...

kameraguy
10-14-2003, 01:37 PM
You the MAN Joey!!! I think that 82 degree thermostat sounds great. I will try and pick that up this week!


btw- someone told me their should be no problems running WITHOUT a thermostat. Is this true???

nokia8860
10-14-2003, 02:27 PM
Originally posted by kameraguy
You the MAN Joey!!! I think that 82 degree thermostat sounds great. I will try and pick that up this week!


btw- someone told me their should be no problems running WITHOUT a thermostat. Is this true???

np man. i know you want a fridge. i answered the 2nd one via mail

Denlasoul
10-14-2003, 05:25 PM
nokia:

you the man. looks like another mod to consider.

CKlasse
10-14-2003, 05:43 PM
Do not take out your thermostat.. your engine will have hard time warming up... then ECM will stay in the open loop. Repetitious event like this will trigger your CEL.

Correct me if I am wrong anyone?

CKlasse
10-14-2003, 05:49 PM
BTW Kameraguy... I was talking about your issue with few guys here. One tech had long experience working on his own S500. He tried all the simplest stuffs until finally he replaced the Radiator itself eventhough there is no apparent problems. Sure enough, his temp is back to normal.

Perhaps after all those things we looked at, its simply the radiator conduction is getting old. :)

nokia8860
10-14-2003, 10:45 PM
Originally posted by Denlasoul
nokia:

you the man. looks like another mod to consider.

sorry man but this is only for the inline 6. I will see what is available for the v6/v8 as they use a different type of thermostat.

kameraguy
10-16-2003, 09:12 AM
Originally posted by CKlasse
BTW Kameraguy... I was talking about your issue with few guys here. One tech had long experience working on his own S500. He tried all the simplest stuffs until finally he replaced the Radiator itself eventhough there is no apparent problems. Sure enough, his temp is back to normal.

Perhaps after all those things we looked at, its simply the radiator conduction is getting old. :)


Thanks for the insight Cklasse. So before your friend replaced his radiator, can you confirm how "hot" it was running on average? And what it typically is at now? Like, after the radiator change, is his car typically dead even with 80 now? And if it does warmk up, what's the warmest it runs now?

If my car temperature doesn't get better after a re-mix of the coolant to water ratio, and possibly a new lower temp thermostat.....new radiator it is.

I know it's one of the costliest things to do in terms if the cooling system...but I suppose over 100K on the OEM is already a good service life. So hopefully if I replace it, I can expect at least another 100K more...

And Joey, your 190 runs PERFECT man. When you say it runs hot...nowhere near as hot as my car!!! That thing was dead even with 80 on the freeway...and you KNOW I was looking every minute! :p

714guy
10-16-2003, 09:55 AM
Originally posted by kameraguy
Thanks for the insight Cklasse. So before your friend replaced his radiator, can you confirm how "hot" it was running on average? And what it typically is at now? Like, after the radiator change, is his car typically dead even with 80 now? And if it does warmk up, what's the warmest it runs now?

If my car temperature doesn't get better after a re-mix of the coolant to water ratio, and possibly a new lower temp thermostat.....new radiator it is.

I know it's one of the costliest things to do in terms if the cooling system...but I suppose over 100K on the OEM is already a good service life. So hopefully if I replace it, I can expect at least another 100K more...

And Joey, your 190 runs PERFECT man. When you say it runs hot...nowhere near as hot as my car!!! That thing was dead even with 80 on the freeway...and you KNOW I was looking every minute! :p

Kam

i heard over time you radiator gets cloged and isn't effiecent, most people only change it when its leaking. That could very well be the problem, I wonder if there is any way that you could flush it out and give it a real good cleaning instead of replacing the whole thing, b/c they dont look cheap at least ours don't.

Eurosport
10-18-2003, 08:13 PM
i missed this thread
but
wholy shit that's expensive towing

mine runs idle to warmup to 80
then stuck in traffic 85-90
freeway 80 sometimes just below 80

i have noticed about 5 degrees lower than these numbers after i put in water wetter, BUT only first day after putting it in, after that back to normal so i guess it's not worth it

another thing to think about which definitely is a common problem is head gasket on these (from history of the car on star report i know mine has been changed by previous owner under warranty at 49k so it'll be good for a long time) but i just hope yours won't go out soon, running hot is a sign for that to happen
hopefully it was the thermostat
gl

CKlasse
10-18-2003, 10:11 PM
Originally posted by kameraguy
Thanks for the insight Cklasse. So before your friend replaced his radiator, can you confirm how "hot" it was running on average? And what it typically is at now? Like, after the radiator change, is his car typically dead even with 80 now? And if it does warmk up, what's the warmest it runs now?


During highway or even city driving, his car was in the 85-90 range. In the traffic, it would go beyond 90. So, he replaced the thermostat and things got a lil better. Then, he noticed lil particles in his disposed coolant. That convinced him to buy a new radiator. Few bucks later... The S class is running perfect. :D

Three Point 6
10-26-2003, 11:17 AM
Kam,

When I first got my C36 I did alot of research before I purchased & I remember a site where a Guy in the Phillipines bought a 'tropics' clutch for his fan which was a Sachs part#. He said it dropped running temps 10-15 degrees. It will lock up a little earlier and do its job. Oh yhea if your a horsepower junkie it will cause more parasitic drag and maybe more noise but I bet it solve your problem cheaper than a new radiator.

Check this site out. This gut apparently knows how to make a Benz run cool............

http://pages.prodigy.net/jforgione/MB_S500.html

kameraguy
10-26-2003, 03:48 PM
Thanks for the link 3.6. I spent some time admiring his S500 coupe before remembering to check out his enginer cooling tips/products.

I am interested in his cool harness. Has anyone tried that? I guess it tricks the engine to turn on the fans earlier than usual. And the testimonials sound promising.

I'll drop him an e-mail to inquire about a w202 as I did not see our cars supported on the list.

The article on properly using WW was very interesting. No doubt this is a must-do as well. I nee done of those AF checkers!!

Well, my car has consistently run between 85-95 degrees...which still bugs me, but I am getting the picture this is "acceptible". But anything I can do to drop it down to no more than 87 degrees would be welcome.

Recaro, have you changed your thermostat yet?

Three Point 6
10-26-2003, 04:17 PM
quote kameraguy

'Is it a sin I think the Crossfire looks cool?'

I started a thread on this over on bnzsport, but I think a 36K mile one will be had for $20k in the next 18 mos or so & an HPS blower installed on the 3.2L will be a fun project car!

DaLawTx
04-29-2004, 09:18 AM
Hey guys,

I am a new C280 Owner, and luckily found this sight right after I bought the car... SO on to my story. I found out that the car was running hot.. 90+ and skitzed out. Clicked on the forum and saw the solutions that you guys proposed. The next day I started having rough idle issues as well. So I came back to the forum only to find that you guys covered that also. I took it in for service, and exactly what you guys prescribed as a fix was what the shop did.

I had a failing thermostat and bad spark plugs.. thankfully nothing else. :D

Keep up the good work and giving out of the Great info.. now if you could point me in the direction of some bad ass mods for this chickies 94 C280

:cool:

Ang

Denlasoul
04-29-2004, 09:45 AM
Originally posted by DaLawTx
Keep up the good work and giving out of the Great info.. now if you could point me in the direction of some bad ass mods for this chickies 94 C280

:cool:

Ang

Welcome and what mods are oyu looking into doing?

DaLawTx
04-29-2004, 09:51 AM
I am looking into exhaust, but as I am told... its mighty expensive to go after exhaust first.. so maybe just babysteps in the mod department till i can pay for the exhaust. I've kinda looked at some other cars on here, I don't want to mod too much just because I like the way it looks already. But I do want to at least do the lowering and get a tint job done on it. I need to shoot some pics of it just to show off my baby. Im thinking of swapping out the interior overhead lights to LED's as well.. (stealing this idea off my M3 BMW buddy) and some other interior items. But i am open to any suggestions at this point.

Any websites you might suggest too would sure benefit me!

Ang:bunny:

J Irwan
04-29-2004, 09:55 AM
Dang...

how did I missed this one.. :(


Kam in answering your question before I did a coolant flushed my car always run in 80-85 temp range even on the traffic..

I guess that might explain why my car still accelerating hard in peak summer time say 90 deg outside..


But after I had my last coolant flush the range goes up to 85-90 range...

but never ever exceed 90 deg...

I know it's weird...., the coolant temp was better before coolant flush..



In my experience with my BMW, I have learned
these are the thing that will attributes to overheating issue:
1. clogged radiator.
2. failing thermostat.
3. failing water pump.
4. failing fan clutch (the fan doesn't kick in soon enough).

PS: If I am not mistaken isn't there is a resister to tinker around in order to make the fan kicks in earlier. Jim with S500 coupe from Mercedesshop seel those resistor I think. (If I am not mistaken) :)

Regardz,

fastmayte
04-29-2004, 12:38 PM
is the fan (machanical radiator one) supposed to move faster and faster as the engine increases in rpms?

mine doesn't seem to be going much faster and seems to be really free while the engine is stalled.

i'm reading over 110 most of the time especially with the a/c on and standing in traffic. cools to 90 when on highway.

need to go electric fan conversion soon.

jnolte
04-29-2004, 01:32 PM
Originally posted by fastmayte
is the fan (machanical radiator one)supposed to move faster and faster as the engine increses in rpms? mine doesn't seem to be going much faster and seems to be really free while the engine is stalled. i'm reading over 110 most of the time expecailly with the a/c on and standing in traffic. cools to 90 when on highway. need to go electric soon.

OVER 110? oh dear god!!!

kameraguy
04-29-2004, 02:02 PM
J, thanks for the info. So is your car still around 85-90 on average? Or did you find a way to drop the temps?

Next month I will do a coolant flush. Maybe the dealership put in a different ratio than what it had before. Would 80& water 20% coolant be ok for summer?

LV202
04-29-2004, 11:10 PM
Thermostats are often faulty out of the box.

Mercedes run hot. Mine sits at 100 in traffic and that doesn't bother me at all. If it's under load and with the AC on it can and will be hotter and that's ok too.

If you don't burp the system when you change the coolant it will cause the system to overheat as well. Trapped air inside is the culprit.


You don't want to drop your car below 85-90 as the operating temp.

J Irwan
04-30-2004, 06:28 AM
Originally posted by LV202



You don't want to drop your car below 85-90 as the operating temp.


Why is that..??


Of all car I have driven or rode , they all have the operating temp at the middle mark. With the exception on mercedes, however the hotter your car runs the more power you loose, the car will feels slugish... (80 is the middle mark on my car)

I guess it all also depend on the climate on where you live.
Lets say if you leave in cooler area but your car operating temp is always near 100 mark while I live in the hotter area but my operating temp is always near 90 mark then something is definitely wrong with your car..

My car has been running 80-85 mark before coolant flush , and now running abit warmer..
Keep in mind that 100 mark is the 3/4 of the max...
If I even run 100 mark as operating temp I'd be worry.. To me that's not normal.. (operating temp should be just right in the middle)


PS: Heat is always bad ;)


Regardz,

Ahmad
04-30-2004, 06:56 AM
yes, all german cars runs on a hot temp say like bmw, porsche, but you can fit a bigger radator to make it run on a cooler temp.

J Irwan
04-30-2004, 07:00 AM
Originally posted by Ahmad
yes, all german cars runs on a hot temp say like bmw, porsche, but you can fit a bigger radator to make it run on a cooler temp.


Not BMW, I have own BMW for so many years that's why I brought it up that most car normal operating temp is right at the middle mark..
(I speak from experience ;))

Porsche: hm...let see prior to 996 model all carrera is not water cooled.. Meaning they don't use water pump and coolant to cool the engine, the older porsche uses air cooled method..

that's why on older porsche if you stuck in traffic for a long time your're toast.. ;)

PS: The only Germany car that I know the engine temp can fluctuate up and down (stop and go on the road) is Mercedes..



Regardz,

kameraguy
04-30-2004, 08:54 AM
Originally posted by J Irwan


PS: The only Germany car that I know the engine temp can fluctuate up and down (stop and go on the road) is Mercedes..





I agree with this, except maybe to add some of the older Audis too! My dad had an '83 5000S which fluctuated, as well as my mom's '87 4000s which was given to me during HS. I drove that car over 150K and it always ran hot if not moving. Very similar to my experience with MB. I don't know about say the newer MBs like the w203 and maybe even the w208 CLK, but I was suprised my car would fluctuate too.

Granted it didn't move much when i first bought the car. At most it would get barely to 85 degrees. Even during summer. But after my coolant flush is when my car really started to hit past 85, which I don't consider "normal" since the car ran "cooler" before.

All my friend's BMWs run "normal", meaning they are usually reading a temperature which is in the middle mark. Even during aggresive driving this rarely fluctuates only unless in extreme situations, but even still the temperature drops back to normal after a short amount of time. Even my friend's E30 M3 appears to be ok in this regard.

But maybe during the coolant flush some air did get trapped. I'll see what happens during this next flush.

As far as ratio of water to coolant, does anyone have a suggestion to bias towards a warmer region of the country?

kameraguy
04-30-2004, 08:57 AM
Originally posted by LV202


If you don't burp the system when you change the coolant it will cause the system to overheat as well. Trapped air inside is the culprit.




I'll consider the trapped air and hopefully try and make sure this doesn't happen on my next flush.



Originally posted by LV202


You don't want to drop your car below 85-90 as the operating temp.


I'm not as knowledgeable about cars as a lot of members, but this doesn't sound right. Is there a reason you feel this way? What do you consider normal and why? I always figured "normal" would be 80-85.

LV202
04-30-2004, 10:37 AM
Well 85-90 is just fine. But I thought I read somebody wanting to get it lower. The car is going to operate more effeciently at a warm temp. If your thermostat is keeping the car temp too low it's going to get crap gas mileage too.

The Benz needles are very acurate. Toyota and Hondas always go up and stay right at that spot under half way. But that doesn't mean the temp isn't fluctuating. It's just where the needle is. So it might make you more secure with the Japanese cars, or more worried with the German ones. But that's just the way they are.

Middle to 3/4 is common UNDER LOAD and if it's hot. I used to run up a canyon in the summer from 4500 ft to 9500 ft with the ac on.
By the time it hit the top it was almost in the red. Then it would come back down. If you are going to get the mail and the thing is spiking up then that's a concern.


Note on burping:


I had a friend get her water pump changed and it started overheating the next day. I took a look at it and could not see much coolant. There was no leak or smoke. We turned the car on, filled it up and burped it too. Huge air bubbles coming out of that thing. The guy changed the pump and for whatever reason didn't fill it up properly. Took us about ten minutes outside of work and everything was fine. The needle didn't budge again after that.

You can also buy a coolant tester for a few bucks to test the ratio of water/coolant.

Ahmad
04-30-2004, 04:39 PM
i wonder if the cooling liquids could help reducing the temp.like the redlines.
http://www.redlineoil.com/products_coolant.asp (http://)

jlomon
05-02-2004, 05:45 AM
One piece of information I haven't seen in this thread is concerning *how* thermostats open. When a thermostat has an 87C rating, it *begins* to open at 87C. It doesn't fully open until 102C. If this is how it is designed to work, then temperatures in this range must be considered "normal". This is information I picked up at mercedesshop.com when I first started my '94 C280 running much hotter than I was comfortable with. It ran consistently at about 87C, except immediately after a run on the highway. When I got off the highway and got stuck in traffic the temperature would soar. But the moment I got rolling again the temp dropped right back down to where it belonged. I remember one time pulling in to a drive-through at Mickey D's right after coming off the highway in the summer, and watching my temperature move up to 110. After about an hour of diagnostic time at the dealer, I was assured that this is "normal" operation. I've had my coolant changed twice since then, as well as having my thermostat replaced when my water pump blew in January, and the car still behaves exactly the same. After years of driving Hondas and Acuras, where the temp needle just moves to the middle and remains there no matter what, it was difficult to adjust to having a temp gauge that actually provides information about what is going on with the coolant temp.

Has anyone changed to a lower temp opening thermostat? Perhaps that 82C thermostat that someone mentioned in the thread? I'd be interested to see what happened to the fuel economy as I suspect it would get worse if the car was running at 82C instead of 87C. I'd like to see if anyone has experienced that. One additional thing to keep in mind is that when we are quoting temperatures based on the needle in the gauge cluster, it is always +/- 1-2 degrees, as that is not a perfectly calibrated instrument.

BTW...on the modification front....I just put in the Bilstein HDs and all I can say is "wow". Just the perfect amount of additional firmness withouth making the ride uncomfortable. I did the plus one on wheels/tires last year, and the Bilsteins finish it perfectly.

Jonathan

SLAMMED_C
05-02-2004, 07:04 PM
My W202 seems to run at 80-85..
some things you will want to check out are the thermostat, new coolant for starters.. check out your fan.. put your finger in the centre of the fan clutch (engine not running!!) and see if there is any wetness there.. if it is wet.. its a sign of leaking. and have a look at your coolant reservoir cap.. check it after your car has been running and let sit for a bit (or you will get a face full of coolant) and see if it is holding vacuum.. when u open the cap it should go pshhhhh.. or something like that! air rushing.
I think all of which was already mentioned before..

cthirtysizzle
05-02-2004, 10:57 PM
Originally posted by kameraguy
I just want to know if this is consistent with other C36 owners. Maybe i'm beeing paranoid, or maybe my car is warmer than others.

I'm bummed out I missed this thread too! Anyways, my C36 runs at a steady 80 degrees. It was 105 degrees here today and my car ran at a steady 80 degrees.

kameraguy
05-03-2004, 08:40 AM
cthirtysizzle, did you do anything in particular to have your car run this cool? Such as do a specific coolant mixture, or change the thermostat?

My car used to run that way, well, it used to never go past 85 degrees in the summer......so I know it's possible to do something to have the car run cooler.

J Irwan
05-03-2004, 08:53 AM
Originally posted by kameraguy
cthirtysizzle, did you do anything in particular to have your car run this cool? Such as do a specific coolant mixture, or change the thermostat?

My car used to run that way, well, it used to never go past 85 degrees in the summer......so I know it's possible to do something to have the car run cooler.


yeah man, I want to know to...:)

The last coolant flush I did, was by the dealership. So it should be using MB coolant ..


Regardz,

LV202
05-03-2004, 09:35 AM
Originally posted by cthirtysizzle
I'm bummed out I missed this thread too! Anyways, my C36 runs at a steady 80 degrees. It was 105 degrees here today and my car ran at a steady 80 degrees.

This is too low. Not good for the car.

Sounds like the thermo is stuck.

kameraguy
05-04-2004, 01:26 PM
Interesting....

I spoke to a service advisor by the name of Mike at Beshoff in San Jose and discussed the temperature guage. When I asked him about the engine temperature and referred that my car was runing a bit warm at 85-90 degrees, he said that scale is actually +100, meaning 80 on the scale means 180 degrees. He also said 185-190 degress is considered "normal".

Does this make sense or sound right?

I didn't know the scale is actually referring to 180 degrees as dead middle.

But anyways, the dealership says this range is normal. Which I know we have all heard before.

So i guess I am curious if the info regarding the temp scale is correct. can anyone confirm?

moebiusgold
05-05-2004, 09:40 PM
In the winter My C36 ran 82 to 83 all the time. In stop and go it shoots to 90 now and turns on the fans. I bought a new Rad and Thermostat. I'll see how that changes things this weekend. My temp scale is clearly marked Degree C. 100 therefor = 212 Degree F.

kameraguy
05-07-2004, 09:43 AM
moebius, can't wait to hear how that combo will work.
I just dropped my car off to get a major tune-up and explained to the mechanic what i was seeing. He checked the usual, such as the fan-clutch and coolant and said that was fine. When he checked my hoses he noticed they were very warm. He suspected the radiator might be blocked or restricted. When I told him the issues started happenning after the last coolant flush he said he has seen that before. It could have been that the last coolant flush circulated the deposits into the radiator but were not completely released. So in essence it made the issue due to deposits not able to circulate through the radiator. So it would seem the flush process might have been the trigger in my case, and possibly Junaidi's.

At this time i'm still running "ok" according to the tech. And he did agree you don't want the car running cooler than necessary. When i asked about including an 82 degree thermostat he said he wouldn't do it unless I wanted a work-around. He felt the radiator was the real issue in my case. But he said i don't need to replace it yet, but if i wanted to make my car run cooler then he'd suggest the radiator replaced since I have over 100K now on the original. He said the 87 degree thermostat is fine.

His opinions on how a c-class should run was that with a car running optimally the needle should be anywhere between 80 and 85 degrees. Under load possibly to 95 degrees but no more than 100. if over 100 he felt there is definitely a cooling issue, especially if it is sustained. Grante dthis is "normal driving" and not driving hard. But either way the cooling system should drop the temperatures down between 80 and 85 degrees once the car's load becomes less. he did agree that the c-class should be in the 80's and not 90's under normal driving. if the car exceeds 87 degrees this is where the car's cooling system should start the process of going into maximum cooling to prevent overheating. if the fans are kicking in at max then that should only be temporarily under excessive heat. It is not normal to encounter all the time. but then again this is what he considers normal where I live. i'm sure in hotter areas the cars will run hotter.

Well, it appears i'll be looking into a radiator replacement soon. I suppose 100K is a lot and if I can get another 100K from the new one then it's not so bad. I just hope it is indeed the culprit. How much does this service cost btw?

714guy
02-09-2005, 10:11 PM
Ok this is an old thread, but my cousin just changed his radiator since his car was over heating at stop lights and what not.
After a normal stop and go drive, his car would spit out radiator fluid from the resivor.

Our Mechanic friend told us to feel our radiator for cool/warm spots as those spots maybe clogged.

Anyways for those who want to change their radiator, get and OEM one. Thats the only way. I got it(97 c280) from Caliber motor Wholesale price $254 + tax which i though was pretty cheap. I am goin to change mine out next month.

Oh yeah his car now runs just above the 80 mark instead of just below the 100 mark. So guess it was a pretty big improvement.

Just wanted to share.

slam96c36
02-13-2006, 07:25 PM
I have the same problem recently regarding my guage temperature going up to 90 degree. I have a 96 C36 currently at 75k..even in the winter, it only took about 2 minutes of driving and my temperature reach 90. Eventhough it stay there Iam still worry. So I did, like everyone here, took into Mercedes Deaership and other MB shop to have them check it out. They couldn't find anything wrong and say it's normal for Mercedes to run at 90 degree. I told them this is not normal (I know my car), when my car use to run around 80-85,even in the summer.

Been planning to get on the forum to research but never had the chance. Kam am glad am not the only one freaking out about this. Thanks for all the researched and answer. I will take my car in and have them check out all the parts and area you pointed out earlier.

Please let me know if you found out anything else to correct this. I hope my car won't have any more problems...this is my first Benz, so I hopeing to enjoy this ride for a long time.