jeanphilippeg

Hi everybody. Im JP, I bought a 1994 W124 wagon about 6 months ago (picture attached) when i crashed my e39 BMW wagon and i used this website quite a bit up to now for repairs.

I think right now i may have some relevant material for you guys.

Since I bought that car, it always felt like it was getting warm pretty fast once off the freeway. It would stay at 90C on the freeway but once i would get off and drive in the San Francisco traffic, it would quickly go up to 105-110C and the the electric fans would kick in high speed even when exterior temperature was only 68F. I replaced the fan clutch and it did not really help. So after that a replaced the radiator, the thermostat and the water pump, cleaned the condenser fans and the condenser coil with no improvement.

With that new fan clutch, while driving the car, i felt like it was engaging only once the engine was past 105C, which made me think: Maybe its engaging too late.

So i looked at the following page and this one and i think i found a way to adjust those:

1- Remove the clutch.
2- Remove the sensing bimetallic blade from the clutch by pushing down on one side and sliding the blade out of the other side. You can see that the slots the blade is in has a deeper recess that lets you remove it easily, without bending it. (see drawing)
3- Remove the actuation plunger. Just pull on it it will come off. What you want to do is to shorten this plunger.
4- Measure the plunger with a caliper and start carefully sanding one end to shorten it 0.2 to 0.3mm. I used some sandpaper i had lying around and it worked great.
5- Put the plunger back in, reinstall the sensing blade and you are done.

I would advice to put the plunger in a way that the sanded part is facing the outside (you dont want any metal shavings to end up in the clutch)
By shortening the plunger about 0.3mm i went from an engagement temp of 105C down to 90C

Remember you can always shorten it more. not less. So if you want to get to a precise temperature, go with 0.1mm steps.

QVHK

I fitted a "cool harness" made and supplied by a Mercedes enthusiast many years back and never worry about temperature going high as this device forces the fan to engage earlier between 85C and 92C.