can you fix a fan clutch? - PeachParts Mercedes-Benz Forum

farmboyhull · #1 12-22-2005, 09:27 PM

on my 92 300d 2.5 the fan is loose. i can grab the fins and move the fan a fair amount. is the only option replacing the clutch? it seemed that i couldn't just tighten the allen bolt, and the little "butterfly" clip around the bolt didn't seem to be the problem.
i searched for the answer here, but all i found was replacing teh whole think. are there other options?

david

waybomb · #2 12-22-2005, 09:33 PM

Interesting. I suspect they can be rebuilt, just like everything else on these cars, but I've always simply replaced them when bad. I'd be interested to know too!

farmboyhull · #3 12-22-2005, 09:36 PM

see, i'm not even sure if it's not working properly temp wise. it's just not spinning right. it's got a hitch in its giddy-up. i was hoping i just had to screw it in tighter.

truthfully, i don't know how they work. mine is simply off its axis.

david

kip Foss · #4 12-22-2005, 09:43 PM

If you know that the fan is secured to the fan clutch and can see that the fan and clutch wobble of the clutch shaft then the only remedy is to replace the clutch.

A suggestion. Do not go asking for a MB clutch. Take the clutch off, go to your local friendly parts house and ask them if you can cross it with a cheaper model. These clutches are not made by MB and probably are not made to MB's design specs. I bet that there are numerous other clutches out there that will fit and cost half what the Mb one costs.

Hit Man X · #5 12-22-2005, 09:46 PM

Quote:

Originally Posted by kip Foss

A suggestion. Do not go asking for a MB clutch. Take the clutch off, go to your local friendly parts house and ask them if you can cross it with a cheaper model. These clutches are not made by MB and probably are not made to MB's design specs. I bet that there are numerous other clutches out there that will fit and cost half what the Mb one costs.

I have an M103 one I'm going to test fit on my SDL's fan, they bolt up the same from first looks. 103 clutches are about half the cost of one for the 603...

#6 12-22-2005, 11:37 PM

I questioned the condition of the fan clutch on a '82sd, it seemed to have excess play just like described here. Turned out to be the water pump. No extra noise or leaks, or cooling problems, just the bearing in the water pump was worn. Take a closer look and see if the shaft coming out of the pump is really where the play is originating from. It is not very obvious because most of the excess movement will be at the fan-the shaft is 2" or so and the fan is like 12", so the fan will have 6 times the movement as the shaft, so the fan is where it is first noticed. If it turns out to be the fan clutch, I'd shop around for a used one, mabee post a want it now on ebay offering to pay $10.

stayalert · #7 12-23-2005, 09:26 AM

Hi David,

As always, good to see you last night. Your wobble is the fan clutch not the water pump. The water pump shaft felt fine. As for your question on fixing? viscous couplings can often be repaired if the trouble is associated with the special fluid (I believe its a silicone type of fluid) leaking out. I believe your fan clutch is beyond repair (I could be wornf thou) My experience is limited with MB but many many cars use the same type of "clutch" for the fan.

Even when the issue is the fluid the most common remedy is replacement. Your car will be much quieter when you replace the fan clutch. Best to do it relatively soon - if the rotating fan breaks off (and I don't actually know the likelyhood of this happening) it could take some bites out of your radiator.

It looked as the the attachement of the clutch to the water pump is similar to that in the 123's....Maybe someone could verify that?

is it as "simple" as getting the little (10mm?) bolts off with a thin profile box end wrench?

stayalert · #8 12-23-2005, 09:29 AM

check it out - MB sez "maintenace free"......

http://mb.braingears.com/124_DISC1/Program/Engine/602_603/20-310.pdf

http://mb.braingears.com/124_DISC1/Program/Engine/602_603/20-5660hw.pdf

hmmmm....They say remove the radiator....Is that really necceesary??

whunter · #9 12-23-2005, 10:29 AM

Added to Cooling System:

Organized MB DIY links
http://www.peachparts.com/shopforum/general-information/135055-organized-mb-diy-links-post1029104.html#post1029104

Rick Miley · #10 12-23-2005, 01:10 PM

If it stops working because the fluid leaked out, then you can get replacement fluid from Toyota. It's been discussed here before, so a search should turn up the part number.

But if the clutch is wobbly, then you'll have to replace it. Take a look in this thread to see what happened to mine: E300 Fan Clutch Failure

farmboyhull · #11 12-23-2005, 02:38 PM

thanks. i'm now wondering what i'd have to look out for if i simply took the fan off. overheating, on my car especially, could be a serious bummer. but if this thing lets loose and rips into the radiator, that would be a bummer as well.
anyone ever take these off?

what about an electric fan? i've heard witha veggie system that an electric fan can help speed things up.

david

stayalert · #12 12-23-2005, 03:03 PM

I dunno....I'd think I'd rather warm up to veggie operating temp. more slowely than risk overheating. It looked to me like there was plenty of space between the backside of the rad and water pump pulley for an electric or dual electric puller if that's the route you wanted to go. Run it (or them) off a thermostat....I think it would be cheaper, less complicated and more robust to replace the stock fan clutch. the mechanical fan prolly costs some fuel efficiency but the electric equivalent would put an additional load on the electrical system. Lots of options (too many?) I suppose. summitracing.com has a variety of electric fans if you're searchcing for ideas...Cheers!

Rob M

Diesel Giant · #13 12-23-2005, 04:11 PM

I don't believe they are rebuildable.

#14 12-23-2005, 04:16 PM

I got a used one that doesn't wobble you can have! But it is for a 603.

Took me two exchanges of new ones to find out there was nothing wrong with the first one!

You may have a cold spot in the radiator that may render the fan un-engaged!

Hit Man X · #15 12-23-2005, 07:37 PM

Testing so far on the 300E one and it DOES fit the 603's fan!

I'm going to order a 300E clutch here and do a trial fit to see if it works. Mounting is the same as well as install height.