'99 E300 running a tad hot - PeachParts Mercedes-Benz Forum

raMBow · #1 07-14-2012, 11:15 PM

I know it's hot out, but seems like the dual fan up front is not always doing much. Should it be a two speed? Seems like when it is hot and I park it the two fans will just barely twirl around and can easily be stopped with minor pressure.

Or is it just the belt that runs them???

Thanks - seems like the temp has been maxing out around 212 degrees at times and I am NOT comfy with that. Fluid is full.

KarTek · #2 07-15-2012, 08:47 AM

The fans are controlled by the air conditioner, not the engine temp. (Or at least this is my observation)

On my car, the viscous fan clutch is so slack that I can stop the fan by hand when the engine is idling, even when hot. This causes the engine to run close to 10 deg. hotter if it's idling for any length of time with the AC on.

engatwork · #3 07-15-2012, 09:39 AM

Quote:

maxing out around 212 degrees

Sounds about right in this summer heat. If you have the car parked/idling with the a/c off what does the temp do after about 5 minutes of idling? How many miles are on the car? When was the engine coolant changed out?

raMBow · #4 07-15-2012, 10:41 AM

Quote:

Originally Posted by engatwork

Sounds about right in this summer heat. If you have the car parked/idling with the a/c off what does the temp do after about 5 minutes of idling? How many miles are on the car? When was the engine coolant changed out?

Has about 130k on it. Coolant changed probably 50,000 miles ago. Guess I'll go out and see how the temp does at idle with the AC off.

engatwork · #5 07-15-2012, 10:55 AM

Let us know. I'd put changing the coolant down for the next service if I were you. Also, how much trash, leaves and debris is between the radiator and the condenser?

When you try it without a/c after it has idled for awhile if it gets to around 105dC see how hard the fan mounted on the motor is pulling. You should be able to hear it. Have someone shut the car off and watch it to see how quickly it stops. If it free wheels for awhile you need to replace the fan clutch. Around 100k is a pretty good life for a fan clutch.

raMBow · #6 07-15-2012, 11:54 AM

Well tried to get the codes out of it and it refuses to allow me into the main codes. I can get into the ones on the right side and had three codes there that I cleared... 231, 234 & 235 - but not reference anywhere I can find as to what any of those are....

The two fans seem to be primary and a slave as one has a motor - I think and the other does not. They seem to be solidly connected.

So - any suggestions on getting codes from climate control system? I've done the HI/LO Rest/EC routine which promptly flashes the Recirc button, but the display DOES NOT display anything else, nor does repeatedly hitting the driver side Auto button do a thing.. tap the right one and got the other codes.

Ok, where would I find trash between radiator and condensor and be able to "see" that? The face of the radiator and its visible fins are relatively free from debris - much cleaner than anticipated. I cleaned a couple weeks ago.

Not liking where this is going.

engatwork · #7 07-15-2012, 12:08 PM

Personally, I don't think you have much to worry about in regards to a 100dC temp indication (other than maybe a coolant change and good radiator/condenser air side cleaning). You have to remove the radiator support and push the radiator towards the engine enough to look down in there to see if you have a build up of leaves and debris. I'm just making suggestions on what to look for and trying to determine if you really have a problem or not. Get the a/c fans out of the equation by leaving the a/c off and letting the car idle and see where the temp gets to.

raMBow · #8 07-15-2012, 12:23 PM

Quote:

Originally Posted by engatwork

Personally, I don't think you have much to worry about in regards to a 100dC temp indication (other than maybe a coolant change and good radiator/condenser air side cleaning). You have to remove the radiator support and push the radiator towards the engine enough to look down in there to see if you have a build up of leaves and debris. I'm just making suggestions on what to look for and trying to determine if you really have a problem or not. Get the a/c fans out of the equation by leaving the a/c off and letting the car idle and see where the temp gets to.

I now see the clips that would allow the radiator to be tilted toward the engine for more thorough cleaning. I cleared the codes and at idle the temp was basically sitting at 182 degrees.

Then AC on and the fan finally spooled up way fast, then dialed down. This is WAY faster than what it has been doing. How could deleting codes cause the fan to work properly?

raMBow · #9 07-15-2012, 12:49 PM

Well I'm presuming I have to remove several bolts to separate the fan and condenser??? If I tilt back the radiator everything comes with it.

Temps still higher than normal, but fan speed is at least up.

raMBow · #10 07-15-2012, 12:58 PM

Here is the readings from the system

1-85
2-94
3-58
4-57
5-118
6-184
7-16
8-141
9-32
10-3.0
11-2.5
12-4.1
20-10.9
21-42
22-00
23-32
24-13.1
40-164
41-32
42-08
43-136

raMBow · #11 07-15-2012, 03:08 PM

Note to self if removing the two bolts that hold the evap to the radiator - secure the two washers that look like oblong hats. Failure to do so WILL result in them ending up at the bottom wedged between the evap and radiator. This WILL take at least an hour to fish them out through a 1/4" gap as you hold the flashlight, improvized tool and hold the radiator out. Yes 3 -4 hands of which I only have two and can't see squat in those conditions regardless.

Elsewhere they say I have a bad engine temp sensor and evap temp sensor - why they say that I do not know. How to replace I have yet to find, but looking - thoughts?

Oh, I was amazed at the amount of crud found between the two.

TMAllison · #12 07-15-2012, 03:13 PM

MERCEDES-BENZ: A/C Diagnostics & Evaporator Replacement

Ignore eb1234, every W210 ever made has that fault. The others may be a result of loss of communication due to low voltage in the past. See if they return before worrying about them.

Your Aux fans are just that, Aux. I'm in Calif and mine have only come on a hand full of times in the past. Your fan clutch does the work and will begin to lock up at low speeds somewhere around 100-105C. If you are in stop and go traffic with teh AC on the Aux fans may come on while traveling at very low speeds or after the engine is shut down. When the fan clutch is locked up the roar of the fan will follow RPM untill somewhere around 3250 RPM when it begins to disengage again to keep it from flying apart.

There is a CCu test to activate the AUX fans. Can't recall it off hand but I know I've posted it previously. It has two speeds.

Other than cleaning out the rad/cooler fins and maybe new coolant I don't see that you've got a problem. Its been hot where you are lately......

raMBow · #13 07-15-2012, 04:13 PM

Have not gotten the codes to come back up. So, I'll have to presume they are from when the battery went dead, thanks Terry. Probably was going to start throwing parts at it due to the codes.

Yep is has been over 100 routinely and now that the radiator is all clean it is running a few degrees cooler as well. I'm probably due for a coolant change as well, though the level looks good.

engatwork · #14 07-15-2012, 05:09 PM

Can you tell anything about the condition of the fan clutch? I'm still not so sure you have an issue with 100dF ambients. Where does the temperature settle out at on 70+ mph interstate cruising?

raMBow · #15 07-15-2012, 06:22 PM

I would have no clue as to what to look for on the fan clutch. I am speaking of the two auxillary fans in front of the radiator which were bringing nothing to the party.

At cruising speed it settles back down rather quickly to its normal 80 degrees Celcius.