Date: Fri, 27 Jan 2006 19:03:07 -0800
Reply-To: Doug F <vanagon@ASTOUND.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Doug F <vanagon@ASTOUND.NET>
Subject: Re: Head Retorquing On New Engine
Content-Type: text/plain; charset="iso-8859-1"
Great info as usual Dennis.
I too was very curious about the sealant under the head nuts being disturbed
or even dried sealant changing torque values.
Question: I know for a fact that Volkswagen had a service bulletin to
re-torque the water boxers as the head gaskets began to fail in huge numbers
while still under warranty.
Any ideas on how exactly the re-torque procedure was accomplished?
Doug Fayne
----- Original Message -----
From: "Dennis Haynes" <dhaynes@OPTONLINE.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Friday, January 27, 2006 5:32 PM
Subject: Re: Head Retorquing On New Engine
> If the studs are good, the cap nuts new, and things are properly
> torqued, there is no need to re-torque the heads. If the heads do come
> loose, it is because the studs are failing. Re-torqueing will only
> stretch the studs' further and in the future, they will loosen again, or
> snap. Also, when they get re-torqued, the sealant under the cap nut will
> get disturbed and this may cause leakage of coolant into the oil or
> externally.
>
> Re-torqueing heads is a left over task from engines with soft gaskets
> that would compress and loosen shortly after installation and a few
> heat-cool cycles. The Waterboxer head sits directly on the cylinder with
> only that metal gasket. The only compression is actually the studs
> stretching. Like a spring, if they are stretched too far, they will
> loose their shape. Also, if they have been overheated or over torqued,
> they need replacement.
>
> Dennis
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf
> Of Stephen DeMocko
> Sent: Friday, January 27, 2006 4:42 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: Head Retorquing On New Engine
>
> Volks,
> I too am nervous 4k mi. into my Go-Westy 2.2L. It has always been my
> belief that you should re-torque the heads, but when I questioned
> Go-Westy about this topic I was told it was unnecessary.
> Stephen DeMocko
> ('85 Westy Luci)
>
> -----Original Message-----
> From: Larry Chase [mailto:roadguy@ROADHAUS.COM]
> Sent: Friday, January 27, 2006 1:31 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: Head Retorquing On New Engine
>
> Richard,
>
>
>
> I totally agree.
>
>
>
> In the case of my AVP ... we did check these at installation.
>
>
>
> All seemed fine.
>
>
>
> But 10,000 - 12,000 miles later 9 were loose enough to cause combustions
> gasses to
>
> leak into the coolant.
>
>
>
>
>
> larry chase
>
> roadhaus.com
>
>
>
> - - -
>
>
>
> On Fri Jan 27 14:17 , Richard A Jones sent:
>
>
>
> >
>
> >I'd suggest that ALL rebuilds be checked before
>
> >installation, not just AVP. My '81 aircooled has
>
> >an engine from an east coast rebuilder and it
>
> >had some through-bolts that were not torqued
>
> >properly and later the heads act as if they are not
>
> >torqued. It leaks coolant when warming up, but
>
> >that coolant isn't an issue. ;-)
>
> >
>
> >I would check all the engine and head bolts before
>
> >putting an engine in. It would be worth the
>
> >small extra cost compared to later. (The aircooled
>
> >has all that tin in the way after installation.)
>
> >
>
> > Richard A Jones
>
> > Boulder, Colorado
>
> >
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