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Old 08-06-2012, 05:18 PM
oldbogie oldbogie is offline
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Quote:
Originally Posted by Chevyfan16 View Post
Intake gasket looks good, head gasket is hard to tell because it's a steel shim felpro. However during assembly I forgot something and had to take the head off after I had torqued it. After it was all said and done I second guessed myself because the head gasket had been crushed already.
Steel shim gaskets are one time crush and are touchy concerning the flatness and parallelism of the block head deck to the head. They are also touchy to the head bolts actually putting down uniform compression between the parts. The use of torque is a secondary function to what's going on which is bolt stretch that actually holds things together. A lot can go wrong the threads need to be clean and undamaged for both the female portion in the block and the male portion of the fastener. Used bolts should always be greeted with suspicion as if over torqued at some point in their life past the elastic limit they loose strength and will not provide the needed clamping force for an indicated torque value. A bolt that feels mushy around the torque value, that is you get there or close on the wrench but it just seems to keep turning without increasing torque is a good bet it's one of these that has been beyond its stretch limit, something to watch for.

Bolts need to be lubricated and in the case of the Chevy sealed. The OEM torque values are for a motor oil lubricated threads and bottom of the head. The Chevy needs a sealant as well which is a place where plumber's Teflon pipe thread sealant satisfies all these requirements.

Bogie
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