124 300E 24v - hot running

[fatherpierre]

I've had my sportline back on the road for just over a week now and noticed she runs hot.

She sits at between 90 and 100 on town running and a bit less on motorways. Is this normal?

She definitely runs hotter than any other Merc I've had, and although running beautifully it's concerning. There's no gunk in the oil, she burns no water and the fan works, kicking in when approaching the 110ish and cooling her down.

So, the head is ok and the fan's fine, so thermostat??? Or do they just run hotter than the usual Merc? Either that or the temp guage is lying?

I've just had her in for a service, so all fluids etc. were sorted, and nothing said by my very good mechanic..............

 

[Asif Kazani]

Thermostat or could be an aged radiator cap. If it does not seal good or it's spring has lost pressure, then this would cause the coolant to boil since the pressure is supposed to lower the boiling temperature. The fan may be fine but the viscous clutch, if it has one, may be bad which could be tested by the carrot slicing trick.

Good Luck,

Asif.

 

[andy_k]

do you have air con?

if so here's a quick tip to trim a few degrees off your running temperature

1, unclip the two clips at the top of the rad which hold it in place

2, remove the big fan shroud

3, lean the radiator back to let you get between the radiator and the condenser

4, clean out that big pile of leaves and gunk that gathers between the two

5, put it all back together.

HTH

Andy

 

[fatherpierre]

Yes, it does have aircon - but it needs the usual re-gas

I'll have a look at it tomorrow using the info provided.

Cheers for the help - great source of knowledge on here as usual.

 

[andy_k]

if you have the twin fan shroud at the front as well give that a good clean with a vacuum cleaner - you really wouldn't believe how much gunk I found in mine when I stripped it all down.

Before you regas it get the system pressure tested - a common fault is that all the rubbish accumulates in the fan shroud and the condenser eventually rots through due to the increased damp. You could also find a big stone sized hole in the condenser, it's in quite a vulnerable position

HTH

Andy

 

[fatherpierre]

I'll have a bash at the suggestions over the weekend, although I'm as mechanically gifted as a banana!

 

[Dave Lewis]

You could look at flushing the cooling system, especially the radiator. My car runs cooler since I fitted a new one.

 

[nothantsw124]

just wanted to say i have the same model and the temp always sits around 90 , i didnt think it was a problem , i thought that would be about normal running temp , should i be concerned?

 

[badshot1uk]

Mines the same too, it allways sits around 90 odd on the motorway and up to 100 ish in heavy traffi. Im having my antifreeze changed on friday, ill let you know if it makes any difference

 

[Brabus3.6]

I've got an M103 but I'm sure our thermostats are the same and open at 87C. Motorway/A-road driving sees temperature just below 90C (ie 87C!) while in traffic it'll rise. Mine doesn't see 100C ever as I've added a resistor across my coolant temperature sensor to make the auxiliary fans kick in just shy of 100C which you can read about here http://pages.prodigy.net/jforgione/MB_CTS.html. All cars seem to be exhibiting normal behaviour .

 

[fatherpierre]

Maybe my other old mercs are running cool! Every (and I've had over 70) other merc I've had always ran cooler than this sportline.

I checked for the recommended bits and all was well. No crap anywhere so maybe it's running normally. I just got a shock seeing the temp guage going so high!

 

[Mercedes cozy]

Have you checked your Engine fan.
Simple test, With the engine OFF, open the bonnet, try and turn the engine fan. If the moves round too free, then its faulty and if it runs fairly tight then its ok.

Please be careful.

I have also a second car 300CE-24V 1991 runs at 80 all times but only in traffic it start to move up to 90.