I have seen heads that the manifold side was slightly warped and could
provide additional sealing problems. In fact many of the 1600 heads were
slightly warped.
I have installed gaskets with and w/o sealants. The last time I used
coppercoat (or is that kopperkoat). Before that I used nothing and never had
a problem.
The torque in the H20 manual says 10 - 20 lbs. I work from the center out
when I tighten the nuts. I don't know if it makes a difference but I do it
that way anyway.
Mike
----- Original Message -----
From: <Geegc@aol.com>
To: <JLBrooksNC@aol.com>; <marc@gracieland.org>; <plhbauman@earthlink.net>
Cc: <datsun-roadsters@autox.team.net>
Sent: Monday, February 04, 2002 4:06 PM
Subject: Re: Header thickness
> In a message dated Mon, 4 Feb 2002 3:22:24 PM Eastern Standard Time,
JLBrooksNC writes:
>
> > I guess I missed the start of the thread...
> > What kinds of problems do you get when the manifold is too thick or too
thin? UNDEQUAL PRESSURE ON THE INTAKE AND EXHAUST SIDES FROM THE NUTS WHEN
TIGHTENING IT UP.
> >
> > And a follow up question... What is the torque specs on the manifold and
carb to the head? GOOD QUESTION, PERHAPS TOM WALTERS KNOWS.
> >
> > And the third... do I use a sealent around the exhaust/carb gasket?
I've heard red RTV... ALSO GOOD QUESTION, SOME DON'T USE ANYTHING.
> >
> > TIA
> > JB
> > 1968 2L
> >
> > In a message dated Sun, 3 Feb 2002 5:42:42 PM Eastern Standard Time,
Marc Sayer <marc@gracieland.org> writes:
> >
> > > No! (Well okay, it might work for a few folks, for a while, but it is
a bad
> > > "solution") You do not want to arbitrarily mess with the
compressibility and
> > > compressed thickness of gaskets. In fact this is generally one of the
worst
> > > cheap fixes for this problem. Gasket design is based on science and
you can't
> > > really just mess with the gaskets like this most of the time. The
proper
> > > solution for a bunch of reasons (including a tendency to warp the
flange) is to
> > > buy headers made with the correct thickness flange. Any other solution
> > > (including gaskets, tabs welded onto the header flange, and stepped
washers)
> > > will only lead to problems. You *might* be able to address a problem
where the
> > > intake manifold flange was thinner with one of these approaches, as
the intake
> > > manifold does not tend to warp, but with a header this is a major
waste of time.
> > > Yes a car maker could perhaps design a stepped or two-part gasket that
would
> > > work, maybe. But an individual does not have the resources to do the
R&D for
> > > this, *and* the issue of header flange warpage is still unresolved
with this
> > > approach. In order of preference the solutions to this problem are;
> > >
> > > 1-get a header with the right thickness flange
> > > 2-use stepped washers (because this way at least the header flange is
the same
> > > thickness throughout)
> > > 3-weld tabs onto the flange (welding on the tabs will warp the flange
and the
> > > flange must be surfaced *after* welding, plus the varied effective
thickness of
> > > the flange will cause warpage problems)
> > > 4-use stepped gaskets (NOT recommended)
> > >
> > > Spray on Copper Coat or just plain silver hi-temp paint (the aluminum
pigment in
> > > the paint acts as a gasket dressing) work well.
>
> /// datsun-roadsters@autox.team.net mailing list
> /// Send admin requests to majordomo@autox.team.net or go to
> /// http://www.team.net/cgi-bin/majorcool
> /// Send list postings to datsun-roadsters@autox.team.net
/// datsun-roadsters@autox.team.net mailing list
|