Thread lubrication on engine bolts

Mike Rocket said:

Does anyone lubricate engine and case bolts with an anti seize grease when refitting them after removal and if so what would you use? Copper slip or alumslip (by Molyslip) anti seize compound?
Is there a problem with galvanic corrosion when using copper slip on steel bolts threaded in alloy?
The question is: Do I use Copper slip, Alumslip or nothing when refitting bolts into the aluminium engine.

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R-III-R Turbo said:

I would advocate following the manual. It directs to lube some engine bolts and not others.
Where it tells you to lube them, it also specifies with what.

I do not like to deviate from manual spec unless I know better, as the torque specs will be different between a lubed fastener and a non lubed. Also some threaded bores have a bottom so excess lube cannot escape out the end and may cause hydraulic lock giving premature torque reading.

On occasion I come across a bolt whose threads have somewhat bonded in place, an impact driver or a few sharp hops of a small hammer will break the grip.

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