Re: [Amc-list] Torque vs Re-Torque

[Frank Swygert <farna@xxxxxxx>]

I would think that AMC progressed with technology as it came along. The 
bedding in procedure isn't the same as the check/retorque mentioned in 
the TSM. The TSM assumes a mechanic would know basic procedures -- like 
bedding in the gasket. The 1930's basic mechanics book I have says to 
torque the head, get it up to operating temp, let it cool, then 
retorque. After that drive it a few hundred miles (don't recall exact 
and don't have book handy -- 200-500?), retorque, then retorque again in 
the 100-1500 mile range. After that follow manufacturer recommended 
intervals. In simpler terms (why can't I just do that sometimes, I know 
some of you wonder!!), the TSM states the recommendation AFTER the 
gasket has been bedded in. I've been 15K miles before retorquing. Seems 
like I went around 20K before the gasket blew about 20 years ago -- 
maybe as much as 25K. But it blew, ran hot, and the head warped and had 
to be replaced. The gaskets also say "no sealer required". Did that, 
gasket blew, ran hot (that's how I knew the gasket was blown!), and I 
replaced the gasket a week after putting a new one in. That was over 20 
years ago. About eight years ago I blew the gasket on an old engine that 
I'd just revived and drove around to much before retorquing (and I KNEW 
BETTER!!!). Thought I'd try using no sealer again. A couple weeks later 
the head was off and another gasket went on WITH SEALER. Don't know why, 
but I'd hate to see you ruin a head trying to find out. New head bolts 
might even solve the problem. It's probably a combination of several 
relatively small items -- thermal expansion/contraction/shifting of the 
thick casting and the bolts, coupled with just adequate sealing 
surfaces. You find out if you want, I'll pass. ---------------------- 
Date: Wed, 19 Dec 2007 18:21:49 -0800 From: Tom Jennings <tomj@xxxxxxx> 
-- Bruce Hevner <scramblr@xxxxxxxxxxx> wrote:

> > If you are using an old shop manual they are probably referring to the old
> > asbestos sandwich type head gaskets. These DID need to be re-torqued at
> > least a few times until they "bedded in".
> Ahh... the gasket I had was not one of those, thankfully. I remember those things! The one I had was not one of the blue-coated sealing types but it 
> was a modern flat solid-composite or whatever.
>
> Did 195.6 OHVs come with those, or did Nash erm AMC simply state the old 
> process every year
-- 
Frank Swygert
Publisher, "American Motors Cars" 
Magazine (AMC)
For all AMC enthusiasts
http://farna.home.att.net/AMC.html
(free download available!)

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