Re: reuse or replace near-new head gasket?
Guys, don't mess with an old head gasket - chuck it. For the few bucks a new one will cost it's worth it to NOT have trouble later.
The main reason not to reuse them is that when a gasket is torqued down it is partially crushed in the process. This is all in the grand plan as it allows the combustion chamber seals (the metal "rings" around the circumference of the com. chamber cutouts) to crush and provide a proper gas tight seal. Also, the beads of sealant (the blue or red tracks) are designed to spread and creep under the high pressure of the head being torqued down down. In doing that the sealant and the com. chamber seals take up all the little imperfections in the block and head faces to ensure the gasket does its job.
If you reuse a gasket you lose all these important features. If its been crushed down and if the engine has been run the tacky sealant would have partially melted too. This is all meant to happen. Coating it with Hylomar (great stuff!) will not restore the gasket suffiently to be used again - IMHO.
Get a new gasket!