Fan clutch won't budge

[lundergaard]

Read the archives. Some folks use the BMW tool, some lodge a 10mm wrench in there to hold the hub still.
I tried the wrench technique and loosened one of the bolts on the hub. Bleh. I've got a Craftsman 32mm wrench i'm using but this thing will not budge if i can't keep that hub still. Fan clutch looks original (240k miles). Dirty and cruddy. it failed the rolled up newspaper test. One on it's way in the mail but if i can't get it off...

Has anyone used a penetrating oil on that 32mm nut, like Kroil? heat? what other methods to remove? the thing is seized on, no doubt, and i would like to NOT break anything. my mechanic will laugh his ass off at me if i have to bring it in just to have him remove it. save me from the shame!!

anyone run into this?

thanks much
andy

[lundergaard]

oh, and yes, i'm trying to turn the 32mm nut clockwise when facing the engine from front...

[Brad D.]

Your best bet is to try to shock it loose. Pop the wrench with a hammer while holding the pulley from turning and it should snap loose.

[RonW]

Shock techniques work- instead of pushing on the wrench, hit it with a hammer.

I don't see any problem with penetrating oil. It's worth a shot, or two.

One last thing- I'm sure you're aware of this, but there's a law that says this must be mentioned in any thread about removing the fan clutch: The nut is reverse thread.

[lundergaard]

yes, reverse thread. definitely going the right direction!

well, damn, i tried the shock technique about 5 times trying to keep the hub from spinning. not easy. i'm sure if i had a metal plate that engaged all 4 bolts i could do it. maybe kroil is the answer...

what about HUGE channel lock pliers with some rubber on the teeth to hold that hub still?

[a]

1st time fan clutch removal has been a PITA on every E 28 I've had. The 1st time on the Borman 6, I used a 24" pipe wrench to hold the pulley. Others, Ive used a big screw driver wedged between 2 of the screw heads holding the pulley on. A strap wrench may.be the way to go.

[craigb93]

Tighten the drive belt adjustment up very tight and then rap on your wrench sharply with a hammer. Most of the time it will break loose.
Re-tension the belt when done.

[Shawn D.]

When you go to put the fan clutch back on, use a bit of anti-seize on the threads and just spin it on until it stops -- do not tighten it. It won't come off.

[lundergaard]

anti-seize is amazing stuff. will use on the threads and hand-tighten.
still trying to get it off. i'll try the suggestion from "a" and wedge a large screwdriver between bolts. barring that i'll start looking for a strap wrench. i don't think a tight belt will do it. it's REALLY on there good.

this IS a PITA. dang.

thanks for the input. i'll keep bashing away on it, literally.

cheers
andy

[CSBolger]

I took a couple of coathangers and looped them through the holes in the water pump pulley, then looped what was left through the alternator bracket. Use at least two though - using only one will cause it to break and send that big wrench right into your jaw.

[moengel]

Put two long 10mm (or whatever size they are) sockets on the clutch bolts and then wedge a wrench inbetween the two to hold the fan clutch still. Then use a wrench/hammer combo on the big fan bolt.

[ahab]

I can't say it emphatically enough. You need nothing but a 32mm wrench and a hammer. PB Blaster also helps a lot. The most amount of room is on the upper hose side, position the wrench at about the 2 o'clock spot and smack it as hard as you can downward with a hammer. Lather rinse repeat. I mushroomed the edge of spinedocab's 32mm wrench with a 16oz Estwing trying to remove the factory set on an '88 car a few weeks ago but after about 30 smacks it spun free. Large adjustables don't always work because they catch the 10mm heads on the pulley and you just end up beating the shit out of your pump. Bike wrenches work if the thing has been off in the last 10 years but if it hasn't you really need a forged wrench.

[lundergaard]

hi ahab
so you are saying whacking the shit of it some 30 times will free it up even though the pulley to the water pump is still spinning with it? I guess i fail to see how that can work. as long as the pulley spins, the 32mm nut should too. i'm for trying it to avoid beating the shit out of the nuts on the water pump pulley... but can you explain how this works? Is it just the impact each time slowly breaks it free? Even without resistance of any kind?

I'm using a giant Craftsman 32mm wrench btw.

thanks!
andy

[ahab]

You need to have the belt on because it will prevent the wrench from spinning on its own and "falling" downwards before you even hit it. Without the belt I'm not sure a really frozen one would come off. Even with the belt on the pulley will slip when you hit the wrench but that's ok, the idea isn't that the belt holds the pulley completely still, it's the sharp impact of hitting the wrench which will break the fan clutch free. Spray the base of the threads first with a penetrant. And yes, make sure when you're hitting the wrench it isn't being held in place by the heads of the 10mm bolts and spinning the pulley by transferring the force. I remove two of the 10mm bolts from the pulley so the wrench has a clear arc to travel and there is no risk of it catching a bolt head.

Edit: It's not going to slowly come off a little bit with each whack. It happens all at once. You'll know when it's worked because it's going to break free and then you can spin it off the rest of the way with your hand.

[stuartinmn]

Another thing you could try, if you have an old fan belt laying around, is to remove the fan belt that's in the car, loop the old one completely around the fan pulley, twist it together a time or two like a rubber band, and clamp it tightly with a vise-grip.

With it wrapped tightly all the way around the pulley it will have a lot more grabbing power, and the twisted together part will give you something to grab on to with your other hand while you pull on the wrench.

[lundergaard]

yeah the belt's on... but that pulley still slips... perhaps enough to stop it from really grabbing.
i'll get some more Kroil in there on the threads. btw, where is the base of the threads? on the water pump side or the fan clutch side?


thanks
andy

[Brad D.]

The base of the threads are on the pump side. I agree with what was suggested a few posts up. I would try either a large pipe wrench around the pulley, a strap wrench or a piece of leather or rubber clamped with a vise grip to keep the pulley from moving.

[ahab]

Pump side. You can try overtightening the belt temporarily too.

[lundergaard]

Thanks guys. I'll give these ideas a try tonight!

cheers
andy

[1st 5er]

I'm sure you're through working by now.

I've always left all the belts on, tightened per specs.
Placed the 32mm wrench on the clutch nut, and hit it with the impact tool.
Don't quit hitting, it will eventually break loose.
I don't think you'll get it by brute force. Penetrating oil sprayed on and left overnight won't hurt.

FWIW here's a picture of the wrench a friend cut for me. Cut from 1/4 inch flat stock.
Also included is the impact tool.

The original version wasn't long enough, thus the weld in the middle.

Edit: I took that picture next year!

[bobaab]

Still having trouble?

Get a friend's help. Have him hold down part of the pulley system so that it stays still. This was my problem and within 5 minutes of him being there, we got the thing off.

[Brad D.]

That's cool Sherman, your pic is from the future!

[1st 5er]

That's cool Sherman, your pic is from the future!

How'd he do that?

[lundergaard]

well i got the SOB off and used yet *another* technique.
i took a flat and narrow piece of steel and wedged it against one of the bolt heads (flat side remarkably) and then put the other end against a long, flat piece of wood against the frame in the engine compartment to distribute the shock... slowly turned the 32mm nut/hub until everything was in place. it STILL took about 10 good whacks to break free!

Put the new fan clutch on, anti-seized the threads and tightened only until the pulley started to turn (maybe 8-10 ft/lbs. i would guess).
test drive tonight. hopefully my stationary overheating problems are over.

thanks guys. i appreciate the input and ideas.

andy

[garageboy]

Hi.

Glad to hear you removed it. Sorry I didn't notice your posting sooner or I would have responded.

For future reference, I know of two definitive methods for removing the clutch. First, there is a tool that will hold two adjacent heads of the fan bolts preventing it from turning while you use the 32mm wrench on the fan clutch nut. It's a factory BMW tool, and I've seen it used quite successfully. If you don't have access to one (through your CCA chapter toolkit or a friendly mechanic), you can theoretically fabricate one and be the envy of your E28/E30 friends.

The tool is basically a long thin slab of metal with a slot cut out where the bolt heads fit. The longer the tool, the better the leverage.

The other method I have used quite successfully is: I got a foot-long "drift punch" (some call it a center punch or alignment punch). Essentially, the end you hit with a hammer is about an inch in diameter, and it's tapered down to the other end which is maybe 1cm in diameter. The idea is, remembering the unit is reverse threaded, to position it at the extreme right edge of the top (horizontal) side of one of the six sides of the 32mm nut. Smack the hammer carefully until it breaks free. I was skeptical when this was suggested to me, but with a bit of patience, and positioned properly, it has worked every time. Penetrating oil is always a good idea when dealing with 20+ yr old BMWs.

Hope this helps,
.steve.
1987 528e, 5spd, 257500 mi, still a pleasure to drive daily
1983 528e, 5spd, 317000 mi, free to a good home, seriously
2001 525i, 5spd, 93000 mi, warranty runs out 11/09, ugh.
NYC, USA

[Donjuan45i]

I can't say it emphatically enough. You need nothing but a 32mm wrench and a hammer. PB Blaster also helps a lot. The most amount of room is on the upper hose side, position the wrench at about the 2 o'clock spot and smack it as hard as you can downward with a hammer. Lather rinse repeat. I mushroomed the edge of spinedocab's 32mm wrench with a 16oz Estwing trying to remove the factory set on an '88 car a few weeks ago but after about 30 smacks it spun free. Large adjustables don't always work because they catch the 10mm heads on the pulley and you just end up beating the shit out of your pump. Bike wrenches work if the thing has been off in the last 10 years but if it hasn't you really need a forged wrench.

I did mine yesterday and this worked like a charm. Hit it 10 times then figured rubber grip on my Crescent wrench was softening the sharp impact I needed, so I cut it off. Tried again 5 smacks later my Crescent wrench flew to the floor rest I did by hand. Thanks Ahab!

[GI jonas]

I always just go for one tool everytime I have to touch one of those things,never fails.

http://www.simsestools.co.uk/images/too ... hisels.jpg



Just position the chisel on one of the hex edges of the big nut and give the trigger a couple of quick pulls.Never fails.In fact its one of the better ways to remove a lot of stuck parts.