original bolt finish

[Chris Cullin]

Thanks Tom. I have found the parts manuals to be very complete in defining the finish & specs of nuts and bolts, atleast for the chassis. The challenge is you have to start with the 356C supplement and go back through every version of the parts manuals until it is defined. This is because the supplement parts manuals are delta's from the previous version.

I have gone through all the manuals for components I am working on, and I have captured in
https://356.miplace.com/

Over the weekend I intend to add bolt head markings and any specifics not captured in the DIN specs.

[Spencer Harris]

Very nice work, Chris.

[Chris Cullin]

thanks @Spencer

[Mark Roth]

Chris,
Please post your final pdf so others can review it. After review, I can post it in the Technical Library in the website.

[Spencer Harris]

This task can make you crazy after a while! The later B & C manuals tend to list quite a bit more N&B details, but (as you've found) even the latest 356C supplement doesn't list details for the Upper Shock Bolt p/n 644.41.511. This piece is not detailed in the '53, 55, or 57 parts manuals or the corresponding workshop manuals that I've ever found.

Greg Bryan published a listing of N&B from his '64 C some time ago, and lists this piece as:

You might consider adding this information in the "Note" row for item 52B in your table.

[Jim Wayman]

Spencer

Is it possible that they did not list the specifics of the shock bolt because it was not a "standard" DIN part? My recollection is that this bolt has a shank larger than the threaded end, so you might call it a stepped bolt.

[Spencer Harris]

Jim,
You're correct, it is a stepped bolt, and the non-standard characteristic is likely the reason for no specs being listed in any of the VW or Porsche parts manuals. (The '50-'59 PET katalog lists the part as "screw, 41.65.02" which may correspond to something, while the later '60-'65 PET simply lists the part as "screw") I'm just surprised that some description other than "Bolt for shock absorber fastening, top" wasn't listed in the factory manuals: overall length, thread spec, etc. None of the parts dealers list any specs that I'm aware of.

[Martin Benade]

For what it’s worth I’m pretty sure that VW used a regular bolt there.

[Vic Skirmants]

For what it’s worth I’m pretty sure that VW used a regular bolt there.

Not too sure about that. The design of the bolt ensures that shear loads are resisted by the larger, unthreaded part, which fits into the receptacle. I would think VW had the same concerns.

[David Jones]

That bolt is identical to the one used on VW link pin suspensions until close to the cessation of link pin suspension use when a regular bolt was used.
I came across very few with the regular bolt when working on Formula Vee race cars
.

[Spencer Harris]

OK, Chris, your thread has been officially hijacked. Please stick with it though as your format and layout are superb.

Wolfsburg West shows the stepped bolts for Beetles through 1962, and what looks like straight bolts from '63 to '65. VW parts manuals are not very definitive, but the '52, '57, and '60 manuals list a "bolt, shock absorber upper, oversize". The '52 manual describes it as M12x1.5 - clearly too large for the female threads on the Porsche bulkhead.

I found this old shock bolt in my N&B bin. I've no idea what year it's from, but most likely A or pre-A.
Head marked RASCHF 10k
Main body 11.9mm OD x 45.2mm L
Step 5.3mm L
Threads M10x1.5 x 14.8mm L
O/A 65.3mm L
ATF 17mm
Relief groove ~2mm L