Just trying to figure out if my car is in proper order - did a search, but no results on my question.

Can anyone tell me at what temperature should the engine reach, before auxillary fan comes on? My car has the clutch fan on one side of the radiator, and ONE electric fan on the other side. I have never seen it on, so I am wondering. Does it only come on when the A/C is operating?

Thanks.

1131 posts and no search results for aux fan? c'mon you are kidding aren't you?

if your 86 560 is anything like my 300E, aux fan is powered up by the AC pressure valve at low speed, with reduced voltage through a ballast resistor, and at high speed (full voltage) by the engine temperature sensor at 105 deg iirc with the actual fan control being run by a relay buried under the fusebox.

i know I've been involved in at least a couple of threads on this, the aux fan and engine cooling being part of my personal MB odyssey

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1987 300e manual 250,000 km (sold)

Uh, I found info on the cooling fan, but nothing about what temperature it comes on at.

The 1986 cars came with a aux fans switch that operates at 110C BUT MB suggests that you swap that for the 100C switch....

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Thanks Doc. I actually have a 1985. That name was from when I first joined. Sorry for the confusion - I should have specified. 85' the same?

No, all of the 1985 & earlier cars use a 100C switch. Single pole switch on t/stat housing

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator

Doc, do you know the part number for the 100c switch for a 1988 300ce? Thanks.

__________________
87 300e (white/black; amg body kit)
88 300ce (red/cream; amg body kit)
93 300ce cabrio (white/blue/blue top)
93 300ce cabrio (black/grey/black top)
98 ml 320 (totaled @ 137,000 miles)
99 clk320 (black/grey/black top)