300E 24V running hot with AC

rainier

Senior Member
Joined
Jan 20, 2009
Messages
161
Reaction score
3
Your Mercedes
300e 24v/1993/3.0l
Hello All,
My old 300e 24v W124 1993 runs ok at just over 80c.But with ac on and when in traffic it goes up to 100c or more depending on ambient temp.
Rad & waterpump & tstat was replaced 2 years ago.Also new headgasket fitted as it was wasted.
It never overheats but always seem to run too hot or is this normal behaviour? The viscous fan works perfectly.It has 2 aux.fans in front of the ac rad but only the l/h one works when temp is up.Never seen the r/h one working! Any input would be welcome as I am worried about ruining the head.
 

television

Always remembered RIP
Joined
Mar 14, 2005
Messages
164,073
Reaction score
377
Age
89
Location
Daventry
Your Mercedes
2002 SL500, 216 CL500, all fully loaded
The visco fan comes on at 80C and the temp will still be rising before the fan can take effect.
Electric fans come on at 100C and that is normal, the front fans have stage 1 and stage 2, at this time of the year the stage 2 may not come on as it does not get that hot.

Nothing wrong at running at 100C as that is the most efficient temp for an engine. You could check out the sensor switches and test the fan that does not come on
 
OP
R

rainier

Senior Member
Joined
Jan 20, 2009
Messages
161
Reaction score
3
Your Mercedes
300e 24v/1993/3.0l
  • Thread Starter
  • Thread starter
  • #3
300e 24v running hot

Thanks for the info.
This car is in spain.As I have mentioned even in mid summer when ambient temp is at 35c I have never got the second aux fan to come on.One day when the outside temp was 40c + the engine temp started to climb uncomfortably as I was stuck in a jam.It only went down as the traffic cleared and returned to normal.I noticed when i disconnect the switch(the blue switch with 2 pins near the t/stat housing) the 1st aux fan speed increases.I gave a live feed to the aux fan wiring connector on the loom and still only the 1st fan comes on.Is there a seperate wiring for the 2nd fan or is it on the same loom as it looks like a real pain to get at the fan to see if the motor has had it.(needs to remove rad and all sorts).
 

Peter Best Insurance is a leading specialist in Mercedes-Benz insurance. All MBO members are eligible for exclusive rates on all our classic car policies.
Call now for our 'BEST' quote. Tel: 01376 573033
Top Bottom