Date: Mon, 8 Oct 2001 02:58:50 -0500
Reply-To: Milo <ovalwindow@YAHOO.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Milo <ovalwindow@YAHOO.COM>
Subject: '82 1.6 Diesel Vanagon Head Bolt Questions (long)
Content-Type: text/plain; charset="Windows-1252"
Hello,
Ongoing head bolt saga continues....
The facts: 1982 1.6 Diesel Westy w/ 64K, new head installed by previous
owner bout 1100 miles ago. He had the head installed by a diesel truck
mechanic, but this was reportedly the first VW the mechanic had worked on.
Things the rebuilder didn't do right:
1.) He didn't torgue the injectors to the proper spec.
2.) He didn't replace the heat shields.
3.) He used non-pressurized hose between the injectors...
Thankfully, he did install a new timing belt, the slippage of which was
the need for the new head in the first place. So at this point, the
mechanic is one for four in the "did it right" category.
I'm 100% sure that these head bolts (12 mm triple box) have not
been turned at all since the head was installed. I'm paranoid that they
weren't even torqued to spec. in the first place, but I have no way of
knowing this for sure. (Or do I? My first question is this. Do the
stretch bolts tighten, or loosen, as they are broke in?????)
I've done my homework. Clymer (discredited in an archive posting on this
subject) - suggests loosening the stretch bolts 30 degrees after 1000 miles
before tightening them again. He doesn't say what to tighten them to
however,
which seems odd. I'm pretty sure this is a no-go however, as everywhere
else
I've read (and heard) says not to loosen the stretch bolts ever, period. So
I think I can safely discard Clymer's advice. But it sounds to me like
Clymer
is inferring that the bolts loosen over time, and that you'd retighten them
back to a specific value...
As for Bentley - I've got both the Rabbit Diesel Manual and the early
Vanagon manual. The early Vanagon manual ('80-'83) doesn't distinguish
between the 11mm (non-strech) and 12mm (stretch) head bolts... It does
say to turn the head bolts 1/4 turn after 1000 miles. The Rabbit manual,
published later, does distinguish between the 11mm and 12mm head bolts.
The Rabbit manual says for 12mm head bolts to turn the bolts 1/4 turn after
1000 miles, which is what nearly everyone who replied to my original query
from the road of a few weeks ago suggested.
My second question is this. Should I make sure these headbolts are at least
a certain torque before I give them the extra quarter turn? (Clymer says
64 ft./lbs, and Bentley said 54 ft./lbs PLUS 3/4 of a turn afterwards for
the rebuild....) My fear is that the rebuilder didn't torque them down
properly to start with, and I'd really like to get a couple of years out
of this head before I have to tear it down myself. Whaddya think?
THANKS! John
