W124 Fan Clutch Shot - PeachParts Mercedes-Benz Forum

i-osprey · #1 09-18-2009, 02:27 PM

It keeps spinning after I shut off the engine and makes a nasty grinding/catching sound when it does finally stop.

I did a search and have read several threads but they all just confused me.

What is the best course of action?

Should I upgrade to the plastic fan?

If so, what car was this on originally?

I just bought the direct replacement for my clutch on fleabay.

Can I bolt on a plastic fan to that clutch?

I really did try to figure this out without starting another thread but they all ran together and just confused me more.

Oldwolf · #2 09-18-2009, 02:39 PM

I replaced mine recently too. I recommend keeping your original fan and just installing the new clutch.

compu_85 · #3 09-18-2009, 02:41 PM

I thought you couldn't get clutches for the metal fanwheels anymore

I'd reccomend you get the clutch and fanwheel from a 606 engine.

-Jason

i-osprey · #4 09-18-2009, 02:59 PM

Quote:

Originally Posted by Oldwolf

I replaced mine recently too. I recommend keeping your original fan and just installing the new clutch.

I will also be replacing my water pump and thermostat at the same time.

Are there any tricks/pitfalls in this repair I should be aware of?

Oldwolf · #5 09-18-2009, 03:14 PM

Quote:

Originally Posted by compu_85

I thought you couldn't get clutches for the metal fanwheels anymore

I'd reccomend you get the clutch and fanwheel from a 606 engine.

-Jason

I got one from Importec a few months ago.

Oldwolf · #6 09-18-2009, 03:15 PM

Quote:

Originally Posted by i-osprey

I will also be replacing my water pump and thermostat at the same time.

Are there any tricks/pitfalls in this repair I should be aware of?

I only replaced the clutch. The radiator fan plastic housing is very easy to remove and once you do, most everything is easy to get to.

i-osprey · #7 09-18-2009, 03:23 PM

I read somewhere on here that you need a special tool to remove the clutch.

Did you experience this?

Oldwolf · #8 09-18-2009, 03:40 PM

No. You can hold a fan blade and use a ratchet to turn the bolt. Only one bolt holds the clutch to the pump shaft. Reinstalling the fan and clutch to the pump shaft is where a tool is sometimes used. I just used a breaker bar against the fan belt to keep the fan pulley from turning when I tightened the bolt back up. Using the breaker bar to push on the belt will keep it from spinning while tightening.

The 602 is shorter then the 6 cylinder version so we have more room under the hood to work with.

i-osprey · #9 09-18-2009, 04:15 PM

That's good to hear.

Thank you.

sixto · #10 09-19-2009, 02:25 AM

According to gsxr, 606 fan in a 124/603 can have clearance problems.

No such problems in a 126 or 140 with 603.

Sixto
87 300D

babymog · #11 09-19-2009, 01:58 PM

Stick with the old aluminum fan IMO.

While it's out, clean and polish it well, I also sprayed mine with a high-quality teflon coating.

Oldwolf · #12 09-19-2009, 02:53 PM

How did you polish yours? Mine was oxidized but if you good way to do it, I'll take it back out and polish it.

babymog · #13 09-19-2009, 06:11 PM

I did it by hand, more cleaned it up and polished lightly to smooth the surface and create less drag, thus the teflon coating. I believe that it has a better airfoil shape and better surface finish as well as thinner material, all IMO should make it more efficient than the plastic fan (which weighs slightly less, but that doesn't affect power/efficiency in any measurable way).

I have a buffer for this stuff, but am afraid I could disturb the balance of the blades if I removed any significant amount of metal, which would of course be bad.

sixto · #14 09-19-2009, 07:37 PM

That's an interesting aerodynamics question - does a smooth or less smooth surface move more air?

Sixto
87 300D

babymog · #15 09-19-2009, 10:33 PM

Smooth should move more air, and an airfoil shape should move it more efficiently. Smooth should also have less drag in most cases.

A rough surface will create more turbulance which (theoretically) will reduce the effectiveness of the wing/blade.

I think that the change from cast alloy to molded plastic was simply an economic decision. The same reason that the mirror bracket was a magnesium-alloy in the early 124s, and zink in the later 124s.