V2Rocket

Talking about the metal collar that the front seals ride against on the 8-valve camshaft and balance shafts.

Need to know the OD (outside diameter) of the seal surface (not the flange).
The SEAL is supposed to be 30mm but I would imagine the sleeve is larger for "seal squish"?

PN is 928-105-139-02
http://www.pelicanparts.com/More_Inf...05-139-02-M260

Voith

I can mesure it tomorrow. Btw picture is wrong, pictured is balance shaft flange.

V2Rocket

I checked the PET - both items have the same PN...Pelican says so too.
Check for yourself 928 105 139 02...is that wrong?

Reason for my asking...I just got the new one I ordered in the mail and it measures 30mm diameter.
The one I took off my camshaft a few days ago (that I've been driving with since 2006) is 32mm. The cam seal fits tight on either one.


**edit** weird..
on Porsche's website "Genuine parts" the 944 1982-1985 shows 92810513902 for the cam collar.
for 944 1989-1991 it shows 92810513904...

V2Rocket

Looking a little further...

There might be 2 options here.
The early PET shows the 30mm sleeve (92810513902) using a 30x47mm seal, (99911328240).
(page 25)
http://www.porsche.com/all/media/pdf...85_KATALOG.pdf


The later PET shows a 32mm sleeve (92810513904) and a 32x47mm seal (99911334940)
(page 27)
http://www.porsche.com/all/media/pdf...91_KATALOG.pdf


...and looking at the parts I have been driving with since 2006...I had a 32mm sleeve in a 30mm seal, and it never leaked!

odonnell

I measured the 2 balance shaft collars I pulled off my '82 engine in a few locations, average measurement was just a hair under 30mm (not measuring on the wear area), so I'd call it a 30mm design measurement.

I took a bunch of measurements last year that I scribbled down somewhere, and I sort of remember that on early engines, the cam seal is the same as the "normal" spin direction BS seal. But on later engines it was different.

V2Rocket

Ah ha!
There was a mid-year/model year change.

M44/07 engines used:
30mm sleeve until engine# 06994
32mm sleeve from engine# 06995 onwards

M44/08 engines used:
30mm sleeve until engine# 21202
32mm sleeve from engine# 21203 onwards

Sleeves got corresponding seals.
M44/09 and M44/10 used the 32mm.

Since the camshafts, onion seal, and cam gear housing are the same across all these engine numbers, the sleeves and seals must therefore be interchangeable so long as they are done in matched pairs.

Page 31..
http://www.porsche.com/all/media/pdf...88_KATALOG.pdf

I even just checked the 928 PET - the same part number supercession took place sometime 83-86 on the M28/21 or M28/22 engines.

...now the question must be asked...WHY would they do such a change? Changing sizes means more parts they have to keep in service inventory rather than having a literal "one size fits all" for cam and B-shafts.

FRporscheman

I came in ready to write what you have found out. Yes, it threw me for a loop as well.

Why? WTF knows, LOL

I use a BS flange and seal on the cam. Easy, done.

V2Rocket

WTF knows is right.
the real kicker is, as i mentioned above...i've been running a 30mm seal on a 32mm collar since 2006!
no wonder it was "shiny"

have a new 30mm seal and 30mm collar waiting to go on.

FRporscheman

Oh, I missed that part, dyyyyyamn!

Voith

This it the right one.

V2Rocket

G, that's the one I had before, that is the later style 32mm.
Up until 85-86 sometime they used the 30mm which is the same part as the balance shaft collar.

I have already put my car back together with the 30mm collar and seal and it's good so far..

FRporscheman

Yep, I figure if it's good enough for a BS, it's good enough for the camshaft which spins 1/4 as fast.

V2Rocket

"BS is good enough for us" - 944 motto

FRporscheman

Not only good enough, BS is at the heart of our cars.

Voith

BS is making our cars smooth.