I was working on a friends 928 clutch yesterday and when we removed the clutch pack and inspected the pilot bearing it wouldn't rotate smoothly, so we decided to replace it.
We tried a number of the "tricks" such as filling the cavity with grease then pushing a punch that sealed tightly with the hole in to force the bearing out. That didn't work, but did manage to blow out the outer grease seal of the bearing instead. We tried the hook style pick tool with a vice grip on it and then tapping the vice grip, but that did nothing. Looked at the other makeshift tools that people had come up with, but they seemed a little hokey, and I didn't think they'd work well.

Went to Advance Auto and borrowed their pilot bearing puller tool with the 2 puller arms. What a POS that is, or at least the one they had for us to use. Ends of the puller arms were bent and barely protruded past the surface of the arms and bottomed out before we could get much pull on the bearing.

Went to Harbor Freight and bought theirs. This is a much nicer tool. 3 prong, cone end to force the prongs apart, standoffs long enough to force the bearing out without bottoming, but doesn't fit through the 928 pilot bearing, at least out of the box.

With a little work on the bench grinder to make the points of the puller arms smaller and more rounded when the tool is closed, it did. I also cut the slider T-handle end off so I could remove and reinsert it instead of having to try and slide it back and forth in the tight working quarters.

The modified HF version worked like a charm.








Thought this might help some others out who were planning to do a clutch with pilot bearing replacement.

 

Another way to do it is by using a bolt, washer and nut - works every time.

 

I had the same problem pulling a BMW pilot bearing. I got the Harbor Freight tool and also discovered it would not close down small enough to fit the pilot hole. So I ground down the inside of the prongs where it rides on the cone. My thinking was I wanted to preserve as much of the hooking surface as possible so it wouldn't slip off the bearing as I pulled it. Grinding it down effectively made the prongs gripping diameter smaller and allowed it to pass through the center hole. I suppose it could have fiddled with the expansion cone as well but I had no confidence I could keep it round as I ground it down. Anyway, it worked for me as your method worked for you. More than one way to skin a cat.

 

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Well done. I used the bread trick with the engine in the car a few weeks ago on my ‘78. Levering the bolt into the hole with a long shank produced better/quicker results than hammering the bolt into the hole.

 

Yep, M8x50mm (or longer) with a nut, plus a 5mm hex key

https://rennlist.com/forums/928-foru...ng-puller.html

 

Nice work on modifying a readily available and cheap tool to do the job properly. There doesn't seem to be a perfect off the shelf tool for this particular job. Here's my modification on a two jaw puller:

https://rennlist.com/forums/928-foru...l#post15791811

Once you have a tool modified, though, it makes this a very easy job. I prefer it to the other methods (bolt and allen key, filling cavity with grease, etc).

Thanks for sharing.

 

I don't fully understand the bread method. Do you put the bread in through the hole with the grease and the bread makes the grease thicker to it doesn't as easily come through the bearing?

Modifying the center section of the HF tool may be the better way to go, but when looking at it, the center splines met so perfectly in a triangle that I was afraid I might not get them as perfect and then the pressure from the center cone wouldn't be even and the puller arms might **** in the bearing. I think as long as the ridges on the arms remain a nice square 90 degrees and you get the cone tightened well against them that it should work fine.

Obviously multiple ways to get the job done.

 

It’s exactly the same as the grease method, except you smush bread into the cavity instead of grease. It’s just a lot less messy with the same results.