Can you leave heads sitting on a gasket overnight before tightening down?

Question

I need 16 for both heads but I only bought 8. It's a Fel-Pro fiber gasket that gets installed dry but there was a little adhesive, from the factory, on there. I guess my worry is that the adhesive activates under pressure and the weight of the untightened heads will spoil it? I'd really rather not go back out to the parts store tonight.

Also, I may have to take one off or at least lift it up a little to squirt some silicone into a gasket that looked like it had a piece missing out of it. Is there any danger there where I might have to unmate the head and gasket for a few minutes after the untightened head has been sitting on the gasket overnight?

Finally, just one last final check... you do install a Fel-Pro head gasket completely dry, right?

Answer 1

As long as you don't tighten any bolts on it, it will be fine. Even to pull the head off of the gasket should be fine. Realistically, while the head itself is or can be heavy, when you spread out the weight of the head over the surface of the deck, there is really only a small amount of weight per square inch which is supported.

There are some issues I'm feeling here though. If the head gasket you have doesn't have sealant on it, you putting sealant on it isn't going to work. The head gasket needs to be a certain thickness which is engineered into it. If you start slathering some kind of sealant onto it, you're more than likely going to have issues. Take the gasket set back to where you bought it and get a replacement set for it.

If both head gaskets are exactly the same, I don't think I'd worry about it at all, but usually, you'll find that they put sealant around holes and it will complete a circuit, not just half of one.

There are some spray on sealants which might be used to help seal the head gasket, but really they aren't needed for everyday non-performance applications. Fel-Pro makes a quality gasket, for whatever it's going onto. Get the head gasket on there and make sure you torque everything to spec. No second guessing what the manufacturer has stated or what have you. Make sure you're doing it right, or you'll find out you're going to not only be doing it again, but you'll probably have more issues you'll need to deal with (like a warped head).