rear axle bearing shims

356 Porsche-related discussions and questions.
Post Reply
Message
Author
Jason Tell
356 Fan
Posts: 54
Joined: Tue Jul 18, 2017 12:51 am
Location: Portland, Oregon

rear axle bearing shims

#1 Post by Jason Tell »

When taking measurements to determine how many shims are needed for the rear axle bearing, what exactly should be on the axle when the bearing housing cover is installed? The backing plate is off, anything else?

User avatar
David Jones
Classifieds Moderator
Posts: 7323
Joined: Tue Mar 25, 2008 6:32 pm
Tag: I wish I knew as much as I think I know.
Location: Kentucky

Re: rear axle bearing shims

#2 Post by David Jones »

Jason there are two pages of instructions in the factory manual detailing how to do it.
Page 17 thru 18.
Unfortunately I am not able post a PDF page thru the forum.
If I had known I would live this long I would have pushed the envelope a little harder.
Cymru am byth
David Jones #9715

Jason Tell
356 Fan
Posts: 54
Joined: Tue Jul 18, 2017 12:51 am
Location: Portland, Oregon

Re: rear axle bearing shims

#3 Post by Jason Tell »

David: I have the manual and read it. It looks like everything goes on -- bearing, washer, spacers, o-rings -- except for the backing plate when taking the measurement of the gap between the flange and the bearing cover. What's throwing me off is the manual says, "To avoid incorrect measurements all components should be installed with the exception of spacers." There's two spacers -- an inner and an outer --
but it wouldn't make sense to not install them. So, do they really mean shims, when they say with the exception of "spacers"?

User avatar
David Jones
Classifieds Moderator
Posts: 7323
Joined: Tue Mar 25, 2008 6:32 pm
Tag: I wish I knew as much as I think I know.
Location: Kentucky

Re: rear axle bearing shims

#4 Post by David Jones »

My factory manual says "no shims should be fitted when the measurement is made" What manual are you reading from?
If I had known I would live this long I would have pushed the envelope a little harder.
Cymru am byth
David Jones #9715

Jason Tell
356 Fan
Posts: 54
Joined: Tue Jul 18, 2017 12:51 am
Location: Portland, Oregon

Re: rear axle bearing shims

#5 Post by Jason Tell »

Workshop manual 1960 edition. Printed in Germany.

User avatar
David Jones
Classifieds Moderator
Posts: 7323
Joined: Tue Mar 25, 2008 6:32 pm
Tag: I wish I knew as much as I think I know.
Location: Kentucky

Re: rear axle bearing shims

#6 Post by David Jones »

And therein lies the problem. My manual is for the "A" and printed in 1956 whereas your is the "B" manual for 1960. Substitute the word shims for spacers and you are good to go.
If I had known I would live this long I would have pushed the envelope a little harder.
Cymru am byth
David Jones #9715

Jason Tell
356 Fan
Posts: 54
Joined: Tue Jul 18, 2017 12:51 am
Location: Portland, Oregon

Re: rear axle bearing shims

#7 Post by Jason Tell »

Thanks, David. That's what I concluded but I thought I would check. You, Vic and others on this forum know so much about these cars. One can learn a lot through trial and error but I'll keep coming back here for advice to avoid as many errors as I can.

User avatar
Graham Kerr
356 Fan
Posts: 217
Joined: Mon Sep 01, 2008 6:21 am
Location: West Sussex, England

Re: rear axle bearing shims

#8 Post by Graham Kerr »

Hi Jason, I've recently had fun stopping leaks from my rear axle assemblies. On determining the axial play I assembled the bearing, one washer the two spacers and the seal and bearing housing of course. No shims, then took the measurement. My particular problem was that I was running VW backing plates which turned out to be about one mm thicker than the Porsche parts. Fitting them after working out the axial measurements would have meant having to use about 8 or 9 1.0mm shims so I surfaced the VW backplates to about 4.5mm and this resulted in the requirement for only two shims. Just to double check the deal I did wipe a very thin smear of blue silicone gasket stuff on both sides of the backing plate and wiped the split pin with a good amount of thread locker. Voila, nil leaks.
86 SSE Turbo Look 3.2 Carrera
Cole Foster Chop
75 Honda ST70
94 Buell ST2
74 Dax Cobra
18 Macan Turbo
62 356B T6 (modified)

Post Reply