91 head gasket retorque on install?

[sewebster]

Putting the heads back on my 91 (VG30E) soon. The dealer manual says to torque the bolts in sequence in two steps, then LOOSEN and torque again in sequence two steps (different final torque value). I have a fel pro head gasket from a engine gasket kit with no instructions. Should I follow the book? The felpro site seems to indicate that their gaskets are "no retorque." The gasket looks kinda like "soft metal" not multi layered. Thanks for any advice!

[madhornet]

definitely re-torque them

[sewebster]

Ok, thanks. My understanding of "standard" retorqueing procedure was the run the engine for a bit before retorqueing, but the dealer manual procedure just involves tightening, loosening, tightening again, so I'm a little confused.

[madhornet]

do as is stated

 

torque loosen and retorque

[unccpathfinder]

Never heard of running an engine and then retourqi g head bolts...

[sewebster]

Cool. Thanks for the advice!

[MY1PATH]

what happens is that some areas (usually near the bolts) compress more.

Compression one way often leads to material wanting to go another way(expansion).

since the rest of the gasket is till under preassure from the rest of the head that expansion has nowhere to go, creating stress points.

lostening relives this stress and re-torqeing the now pre-compressed gasket gets you your final, flush and stress relived seal.

I know it sounds silly and usually these types of stress forces don't happen on a visual level so people have hard time beliving but it does happen.

Edited September 26, 2010 by MY1PATH