Fan scrape
 

87 3.2. Fan once in a while scrapes the housing on the bottom. Done this very seldom since I bought it 3 yrs ago. Then the alternator went bad and I just replaced it with a pp rebuilt. Now the fan scrapes even more. It only does it when you have driven awhile, shut the engine off, wait 5 mins or so and crank it and start. It scrapes for 15 seconds, then stops. Any thoughts on how to fix this. It's the original fan and housing.

When off the car doesit bind? Which belt are you using and how many shims in and out?

Make sure the fan housing is seated properly. Sometimes its tricky to get it seated just right.

May want to make sure the fan belt is not too tight.

Also, be sure the alternator itself is seated properly in the housing.

Make sure your fan strap isn't too tight. I do t have the spec in front of me, but IIRC it was quite light.

Did you check to see if the fan housing is cracked? If it is maybe when you tighten down, you may have squeezed it and now its out of round

The fan housing mounting strap allen bolt tightening torque is 18 ft lbs per Bentley.

A few tens of thousands of miles ago mine would scrape where I had a bubble in the magnesium housing - took it apart and sanded the bubble down and it's been all good since.

Chuck.H
'89 TurboLookTarga, 362k miles

Thanks guys

I'm using a porsche belt with 3 shims inside and outside
Pretty sure I put the alt into the housing ok
Might have the strap bolt over tight or the housing is out of round?
I'll try to move one shim to the outside on the belt and do 18 ft lbs on the strap
Thanks all

Take the belt off and make sure the alternator is secure on the mount. If the bolts securing the alternator to the assembly are loose, it will rub. Next, make sure the alternator itself does not have play in the shaft.

If none of the above suggestions help (not just mine - the others are excellent points) then you may have to just take it apart and examine it. These housings can crack and it does change where the fan and alternator sit in relation to the lower part of the housing.

angela

Agreed. I'm going to pull it out and check things carefully. Including checking cracks and out of round.

+1 on your last post--great plan to check for cracks and out of round. Also look for scrapes in the inside of the fan housing, especially where you think its rubbing. A failure could be catastrophic. :eek:

After cleaning up my fan and housing and re-installing everything, the fan touched the housing at the lower part. When running the engine, it was clearly audible. I dis-assembled it again but couldn't find anything. Same thing after re-assembly. Then I loosened the belt by putting one more shim on the inside of the pulley and the interference was gone.

- Manfred

Who would think one shim would do the trick! I'm trying that first for sure. If not, then it's all comes apart for crack and roundness.

The cracks I think you will look for, if you have to do that, are probably in one or more of the "arms" which connect the alternator mounting part in the middle out to the circumferential housing of the whole assembly.

Ok moved one shims inside and re tightened the strap bolt to 18 ft lbs. will try it tonight. Too hot now in Dallas today. Will let you know

18 ft/lbs is too tight! As seen on Pelican, the spec is around 72 in/lbs. 18 ft/lbs will most likely distort the fan housing.

Bentleys shows the Allen strap bolt at 18 ft lbs. so which one is correct?

Yer worrin' too much. Get a short wrench and snug it down tight. It'll be fine.

Seat the alternator without the front fiberglass cone first using the 6 nuts. Once its seated, remove the nuts and re-install the cone.