Cwn74@aol.com wrote:
> In a message dated 8/18/2002 2:05:18 PM Eastern Daylight Time, Cwn74@aol.com
> writes:
>
>
>>The metal is softer when hot and
>>will compress some.
>>
>
> Also the studs will stretch when/while hot and you need to tighten them up!
Here's the deal as I understand it: when hot, the studs expand in
length, which relieves the clamping force that was set when cold. Say,
for argument's sake, you established 1000 lb. of clamp force on the head
gasket when torquing the nuts on cold studs. Then heat the studs, so
they stretch, so when at operating temperature, the clamp force is
reduced to something considerably less than 1000 lb. Ka-blooie.
Therefore, re-establish the original clamp force by retorquing while hot.
Of course this means the clamp force goes way up as the engine cools and the
studs shrink... to the point that they can fail. So pay attention to the specs
and don't buy cheap parts!
--
--
Douglas Frank DigitalWhoopsCompaqImeanHP Co.
ZKO 110 Spit Brook Rd. The older I get,
603-884-0501 Nashua, NH USA 03062 the better I was.
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