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Loose fan clutch

Posted: Thu Dec 24, 2009 1:13 pm
by Shoup
Hi all, I have a loose fan that made a lot of racket on my way home a few days ago. The fan clutch has about a 1/2" wiggle which is letting the blades hit one of the pulleys. The fan clutch is the old one with a big central bolt and I have tried tightening the bolt with no luck. I can loosen it but it wont tighten past a point, it just turns the whole belt assembly. i even got a friend to try to hold the belt assembly still while i tightened but that didn't work. The fan clutch seems to work properly but i didn't check it for long because i didn't want to damage anything.

The car is a '75 530i. mostly stock (for now).

Is there a trick to getting these fitted properly? do you think something could be broken? can i install a make-shift clip-washer type thing to eliminate the wiggle? (that is just the hidden engineer in me). I have read some other posts about these fan assembly's and i would rather not remove the rad to fix this but that looks like my only option. Any input would be appreciated.

If i do have to take the rad out I'm going to do it right by upgrading to the e28 rad, get a new water pump(the one in there has 140k on it i think), and install an electric fan. Does anyone know a good elec fan kit?

I am assuming this loose fan is because i let my local mechanic replace all my belts to pass emissions test a few months ago (my airpump belt had withered away and the others weren't much better). it was cold and i didnt feel like taking the rad out myself so i let them do it and now i have problems... They also severely dented in the rad fins directly in front of the fan before they realized it wouldn't fit. There is a huge dent in the shape of the fan clucth in my rad, and when i mentioned it the guy said it must have been there before they worked on it... live and learn i guess.

Thanks for any suggestions or tips, you guys are always so helpful.

Posted: Thu Dec 24, 2009 1:50 pm
by Peter Florance
The spacer behind the bolt has two tangs that fit in 2 slots in the water pump. If the are not in the slots, it will wobble

Might want to check that.

Posted: Thu Dec 24, 2009 2:01 pm
by Mike W.
There is the washer there (for lack of a better term) with tabs in it that has to fit into the casting that bolts onto the water pump as Peter mentioned. Everything has to be seated, then the bolt tightened. However I have had a couple fail by obviously loosing the viscous fluid and they then kind of spun freely, but with additional play in them (never as bad as you apparently have) clearly failing with metal powder all around and creating a scary noise as it would intermittently freewheel, then bind, grab and spin while driving. Below is what the "washer" should look like.

Image

If it is the clutch and you want to go used, I have several used ones and I'm not greedy, PM me.

Posted: Thu Dec 24, 2009 3:08 pm
by T.Hanson
Happened to me. Second previous comments, adding I gave up trying to get it right, radiator in place.

Checking the notch was in place, mine didn't tighten until the last turns. Kind of a wiggle the fan, tighten the bolt deal, and then it feels right.

Posted: Sat Dec 26, 2009 3:54 pm
by Shoup
Thanks guys, I'll check the "washer" type thing and see if i can wiggle the thing back into place. I will let you know how it goes. i have to wait till the snow melts first so it might be next weekend till i can get to it.

Shoup

Posted: Tue Jan 12, 2010 12:18 pm
by Shoup
Thanks for your help guys, here is an update; my project is finished. The Fan Clutch was not working (spinning and not spinning randomly) even after i adjusted it to fit properly. So i decided to get an electric fan from flex-a-light, a used e28 radiator, and all new coolant hoses from AZautohouse. All for 1/3 the price of a new fan clutch!

The e28 radiator was a little banged up but in much better shape then what i was using. the install was easy i just followed the guidelines on the FAQ page and it went smoothly. I didnt need to buy the e28 thermostat housing as some people mentioned they did.

The electric fan was a 16" flex-a-light rated at 2200CFM i believe. I had also purchased the mounting kit for $5 so i wouldnt have to bend radiator fins to mount it. But i couldn't figure out how the 4 brackets that were in the kit could be used to mount the fan without going through the radiator still. So i just poked holes in my rad and there was only one small leak created and then i easily repaired it.
The fan works great, i got a temp control switch so the fan only runs when the coolant is warm.

There was not enough room in front of the rad for the electric fan because of some stripped hex-bolts where the old fan clutch was mounted. so i had to take out the AC condenser (maybe, not sure what its called) and put the fan in front of the rad and change it to blower mode. That took a little time, but the AC was the old system and it didnt work so i also took off the pulley for the AC. I also took off the useless airpump. My car had better emissions but failed the test because i had removed the airpump before. I was amazed that my emissions were worse with the airpump on.

All in all i spent 8 hours and learned a lot about my car's cooling system. I also had a blast, these cars are fun to work on and then enjoy once they are fixed up.

Thanks for your input, i appreciate it!
Next up: either changing out the thermal reactors, or upgrading the suspension.