Date:         Fri, 26 Dec 2008 16:26:02 -0800
Reply-To:     Roland <syncronicity1@GMAIL.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Roland <syncronicity1@GMAIL.COM>
Subject:      Re: Two bolts to mount the alternator bracket to the engine block
              are just plain missing!
In-Reply-To:  <BAY132-DAV4CAA59F07F321C8800FABA0EB0@phx.gbl>
Content-Type: text/plain; charset=ISO-8859-1

Joel, Dennis,

Thanks very much for the quick reply and detailed information.

In the meantime I drove over to the VW dealer to see what they have, or what
I could learn.  The normal parts guy was on vacation, so I got a mechanic
staffing the parts counter which was much better.  Rather than the EKTA
pages that Joel sent out, he called up a page illustrating the engine block
and the part number for the studs was visible.  You can see the stud just
barely in the 2 pages that Joel sent out, but it isn't labeled.  It is where
the nuts / spring washers 6,7 and 9.10 go in the EKTA drawing above.

So, the stud has to come from Toronto and will take 5 days -- uhhh...  So
the parts guy (mechanic) found a couple of studs with the same spec in the
parts bin and I bought those.  They have a side with 25 mm of thread on one
side, and 15 mm of thread on the other side.  We were guessing at thread
pitch, but I think we got it right.  I got the stud into one of the holes
about 4- 6 turns so that gives me good confidence.  And I measured 8 threads
over a 10 mm interval which sounds like Dennis' pitch of 1.25 he mentioned
in his mail (thank you!).  The studs that I got appear to be that high
quality hard steel, also got matching nuts / flat washers.  Again it was a
mechanic so I think he probably picked the right stuff.

So, now the tough part:  I have no idea why there are no studs in these
holes.  They didn't break off!  I can insert a probe 25 mm into the 2 holes,
there may be some debris in there, but that is all, both the holes are
clear.  I need to clean them out.  I've had this Syncro for 3.5 years now,
has close to 200K miles, so clearly somebody must have done some work on it
as some point (head gaskets as a minimum I suppose).  Very puzzling, maybe
the studs were replaced at some point, and they forgot to use locktite?  And
now they just wiggled out?  I've never done any work, nor has any been done
in this area since I've owned it.

Still not sure of the root cause.  The alternator shaft turns freely,
however the belt is toast, lots of bad (thin) spots.  Maybe (like Dennis
suggested) the bad belt caused the wiggling which then worked the
studs/bolts loose?  Tried to send pics but it got rejected at the list
server :(

So a couple of lingering questions:
- I bought the blue lockite, i.e. the medium strength, should I have gotten
the red, i.e. high strength?
- prior to seeing Dennis' email, I bought some split ring lock washers.  Now
I see in the EKTA above that they should be spring washers.  Dennis, what is
the risk with the split ring washers?   I may have to wait until tomorrow
and go back and get the spring washers.
- Any suggestions on stud installation?  I figure 2 nuts back to back on the
outside and then simply keep turning them in.

Thanks again for all your help!  I still can't believe there were properly
installed studs in there.

Roland
'89 Syncro
Escondido, CA



On Fri, Dec 26, 2008 at 2:18 PM, Dennis Haynes <d23haynes57@hotmail.com>wrote:

> It is unlikely the studs are missing. They are originally a class 3 thread
> fit and glued in place. They are more likely broken off and you will need
> to drill them out, restore the threads and replace the studs.
>
> They are studs for a reason.
>
> They broke due to a number of reasons including the wrong property class
> of the nuts, cheap washers, and if used, lock washers.
>
> Other causes include a defective alternator, (bad bearings, out of balance
> rotor), lower alternator mounting bolt loose or housing worn, or loose
> belt.
>
> The proper thread size id M8X1.25. The minimum P.C. is 10.9 for the stud,
> washers, and nut. Split lock washers should not be used here or for
> anything that matters. Yes, nuts and lock washers do also come in grades.
> My choice for a nut here is an all metal, class C prevailing torque lock
> nut with a through hardened washer.
>
> After installing a belt, the lower alternator bolt needs to tighten. If
> you can easily adjust the belt without further loosening this bolt, it is
> too loose.
>
> Dennis
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
> Roland
> Sent: Friday, December 26, 2008 4:44 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Two bolts to mount the alternator bracket to the engine block are
> just plain missing!
>
> Hello folks,
>
> Quick question.   My alternator was wiggling.  The bracket under the
> alternator mounts to the engine block with 2 bolts (maybe).  Both of these
> are missing, maybe they just worked themselves out, maybe a prior mechanic
> forgot lock washers.  I looked in the Bentley and it doesn't provide a
> spec.  Even worse the Bentley shows that there are supposed to be 2 studs
> that the bracket mounts on with 2 nuts!  Hey, I got no studs there.  I am
> happy to replace them with bolts, if I can find the right size, but please
> tell me if this would be a bad idea.
>
> But mainly I need the thread size for these studs/ bolts.  I measured a
> hole
> of about 25mm, and the bracket is about 10 mm, so I think a length of
> about
> 30-35 mm should do, assuming another 2-4 mm for lock washers.
>
> Thank you very much.
> Roland
> '89 Syncro.
>
>