260E overheating FAST...
What could be the problem?
I have replaced the belt and the tensioner tightened up, so safe to say it is OK?
Radiator could be original, water pump is almost certainly original.
I am using Zerex G-05 coolant and the level looks ok. Cap releases pressure when I take it off, so I don't think it is a cap issue.
Any ideas? I cannot run like this or I will certainly blow the head gasket real fast.
But either way, it is something more than a fan clutch. It's gotta be a flow issue.
If you aren't sure, check the hoses a few minutes after startup. They should begin to warm up as the car does. If your car gets hot, and they don't feel as warm as you would expect for 100C water to be flowing in them, I would suspect the T-stat.
Last edited by rivcal4life; Jun 30, 2010 at 01:02 AM.
I have a feeling its gotta be a flow problem rather than fans...but then again I don't have much experience under my belt.
The hose before the TStat is red hot, so its gotta be working to some extent...For $15 though its a no brainer.
I hope it is not the tensioner or water pump though...
Last edited by ps2cho; Jun 30, 2010 at 09:21 AM.

I found the correct procedure to filling the coolant, so I will do that when I replace the radiator this time around.
By time I have paid a mechanic to diagnose it, I could replace half the system myself and be that step closer to a long lasting engine.
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Thats about all I can think of.
Hope I'm not jynxing anything, but you may have another headgasket failure. You may have had a crack in the head previously that went unnoticed.
Is there any loss of water pressure at all? Small leak can lose water volume and pressure for flow.
What is your temp when it's not 105 ambient? Is this the first time your car was in this high of temp?
Is the temp same when on highway and in traffic?
Is high temp with or without A/C on?
Is the temp accurate? Use another instrument to confirm.
Is the fan guard and lower engine panel installed?
Are the AMG front bumper lower front vents open?
Agree with checking for air bubbles that can prevent flow.
No drips or coolant loss.
I have no issues at all here in socal, even in 95F days. I guess the lack of moisture in the air in Arizona?
I left the car in AZ and flew home...so when I move out there next week I will tackle the issue...Thanks for the ideas guys.



