Is it normal?
 

Ok, I've been worried that I've had a cooling problem since my 83 240D heats up on the freeway rather than city. Today it was 110-113oF and I was driving kind of uphill with the A/C on (of course :P) and the temperature guage rised to dead middle between 120 and the white line above 80 (so i'm guessing between 90-120) and just sat there... Is this normal under these conditions? :confused: Or should I be worried?, I was told the radiator cores might be blocked but after looking at them and washing them it's still doing it... but it's under hot conditions. what do you guys think? Thanks again!! :D

I had similar issues and replaced my radiator rather than trying to flush it. Now my temperatures, rather than being 115C-120C, are around 85C-90C at freeway speeds with A/C on, ambient 95F.

You're running a little bit hot at 100-110C but it could be worse. Flush your radiator (disconnect rad, remove from car, pour in CLR, leave overnight, flush well), change your thermostat, change your coolant and you'll probably see a big difference. After consulting around many places, an "out of car" radiator acid flush (with CLR or HCl or Citric or whatever) is preferable to doing one in-car where the chemical can eat through seals and gaskets and so forth.

Congrats on having a working A/C in your car btw, apparently thats a rarity ;)

in your previous post you said you have a coolant leak. can you take a picture and post it so we can see how bad the leak is. also that t-stat needs to be replaced. i can't believe it got that hot out there today here in the IE it was only like 90 or so. and like i said in the previous post make sure you be careful with the t-stat housing bolts. if they break its not the end of the word it will just add some frustration to the project.

I want to get a new thermostat and do the coolant flush like you said. Thanks about my air conditioning.... :D It was retrofitted to R13 and man is it great! It blows colder than my 300E ever did. Very nice to have in these hot as hell summers. I can't belive it's getting this hot either..... Can't wait to see what it's going to be like in the middle of summer 125oF? 128oF? ugh.... Ok the thing with the coolent leak is this mechanic that is starting his owns buisness claiming he worked for mercedes for like 10 years saw this leak which he tells me is a head gasket leak and it's where i'm leaking coolant. But I checked the coolant color and it's green... The fluid that is coming out of the eingine block in the pictures looks red... the tranny has it's own leak so the stuff that's on the floor in the morning is tranny fluid. But i don't know what is coming out of the block.... I don't know if this is why it's heating up or what. :confused: It's not letting me repost the pics, so I'll bring up the 1st thread and the pictures are in there :)

where is the red color coolant coming out of the block.

oh just saw the pics it looks like rust to me. If the coolant has been in there awhile then it can create rust. just flush it and drain the block. there is is drain bolt on the passanger side of the engine take the bolt out to drain the engine when you are ready to flush the rad.

I have a related question.

The gauge has hash marks numbered 40, 80, and 120. I'm assuming the un-numbered hash mark between 40 and 80 is 60 and the one between 80 and 120 is 100. Is that correct? They appear to be pretty linear and evenly spaced, but I thought I saw where someone said in another thread that the hash mark between 80 and 120 was 90*C...

I ask because I just swapped my t-stat and now instead of reading somewhere between 80 and the hash mark below it (which I assumed to be 60) it now sits between 80 and the hash mark ABOVE it (which seems like it should be 100).

since 100*C = 212*F somewhere right around 100 seems like it should be optimal for engine efficiency - right?

Ok cool, will do! So do you think I still have a failing head gasket? It puzzles me because it's not wet (the white stains) it just looks like it happened a long time ago and like you said it could be rust.. although it's white.. :confused: sometimes there is a little tiny bit that dribbles out at times but not enough to drip down onto the floor..

if you have a leaky head gasket it will leak inside the cylinder most of the time. So you wont really notice any liquid. Do you have **** smoke on hard accelerations? if you do the head gasket does have a leak and will need to be replaced. as for the color of the coolant dont replace with green replace with the mb coolant or zerox G-05 i think that is what its called.

I havn't seen any smoke when i'm driving, looking back. I'll have to drive infront of someone so they can tell me.. I'll flush and replace it with the MB coolant, just, how much does Mercedes charge for it? Can the zerox be found everywhere? i.e. autozone? :P Thanks again! :)

Rcounts, wouldn't it of made life so much better if they would have just numbered that line! :P it puzzles me too I think it's 90? Or 100?

the zerox stuff can be found anywhere. you might also want to find out if your temp sensor is actually working correctly and not giving you a false reading. borrow a infrared temp reader and read on the t-stat housing to see how hot it is and compare to your gauge if wrong then replace temp sensor.

(temp sensor driver side engine where all the glow plugs are at, just not a glow plug, sorta looks like one)

woOt
 

ok awesome! will do just that! Thanks so much you've been a big help! this forum is sooo pimp!!!! :D

Autozone doesn't carry the amber coolant, but I found one there that said it was safe for aluminum parts so just used that.

Sorry, but you don't have near enough info to make that diagnosis! Come on.........:rolleyes:


**Edit**
His pics are here: http://www.peachparts.com/shopforum/showpost.php?p=1854795&postcount=13
Let's hope that hose into the block is where the leak was.......:eek: