crown wheel bearing removal?

adam911 · 06-14-2012, 04:33 PM

So, what's the easiest way to remove the roller bearings from the crown wheel?

I've searched these forums with no luck thus far.

Any help much appreciated

Adam

TimT · 06-14-2012, 05:55 PM

you need a press, and bearing splitter

KTL · 06-15-2012, 05:27 AM

Jaw style puller works too. Also need an insert placed inside the diff housing to give the puller something to bear and center itself on.

However you have to modify the jaws by grinding the tips, in order to allow the jaw to reach around the bearing cage and pull on the bearing race for a good grip. Otherwise you end up destroying the bearing. I guess if you're replacing the bearings then it doesn't matter if you destroy them. But often times you're pulling them off multiple times to get your shim stack sized properly

adam911 · 06-15-2012, 06:55 AM

Thanks for the reply.

Which brings me to my next question, will a new bearing go on like for like or will there have to be adjustment of the shims. I've been through this thread on 70-71 901 transmission rebuild
1970 (911/01) transmission refurb issues

But there's not a lot mentioned about these shims.

Thanks

Adam

Peter Zimmermann · 06-15-2012, 07:26 AM

Read the diff section of...

Welcome to Red Line Porsche Wiki - Porsche Wiki

Scroll left side of page, click on "915" under page tags, and you'll find my 915 repair tutorial. There are some differences, but at least you'll know how to do the procedure. Also, it would be helpful if you could find an early factory manual set (eBay, etc), which is by far the best source for repair info.

adam911 · 06-15-2012, 07:42 AM

Thanks Peter, I'll take a look.

adam911 · 06-15-2012, 08:15 AM

My main problem I'm dealing with here is a broken cable retainer on my serviceable tranny. I have 2 spare units, each with it's own problems (one had catastrophic crown wheel failure, the other appears to have been rebuilt, but there is grinding when engaged in 4th or 5th), but the cases are good on both. So, I'm wondering if I can simple take the intermediate plate with all gear sets from the box with the broken retainer and simply transplant if into a box with a good cable retainer? Secondly, would it then just be a case of resetting the pinion depth via the shim gaskets on the intermediate plate?

I'll shall keep reading, but this is the crux of my problem and while it would be good to learn to rebuild these, at this moment in time simple swapping everything over without completely dis-assembling the gear sets from the relevant shafts would be preferable.

Adam