ok, I bought a used engine to use as a donor for some parts I was going to polish up and install on my 2.8.

The gaskets on the donor engine look great, even the valve cover gaskets. Do I have to buy new ones, or is ther anything wrong with using the same ones over again?

also, do I want to use any kind of sealant on them? I've got plenum gaskets, throttle body, EGR, and valve covers.

 

If the gaskets are rubber, it's usually not a problem to reuse them. The paper and cork gaskets, should probably be replaced if there's any question. Fresh gaskets are cheap for the peace of mind they provide.

That said I reused the intake gaskets on my 3.1 Firebird and I had that intake apart at least 5 times. Anything from the lower intake gasket down I'd replace. If the car isn't a beater I'd probably spring for new gaskets if you're not planning on having apart again anytime soon.

 

Thanks Drew. I take it since you said you re-used gaskets, you've never used any kind of sealant on them?

 

Right. At least in the intake. If you're sealing air it's not that big a deal. If you're sealing oil, or water, you might want to break out the RTV or the gasket shellac. You shouldn't ever need to put anything on rubber gaskets.

 

I reuse gaskets often. If the part surfaces aren't flat then I file or sand them flat. I commonly use sealer on just one side of the gasket, and lube the other side with grease.
For certain gaskets I do use sealer on both sides, - it just depends.
If they don't seal, but the part surfaces are good, then the gaskets may need sealer, or to be replaced. I don't use one rule for every situation.

If an intake doesn't have pressurized coolant running through it then I generally don't use sealer on both sides. I find it handy to have the gaskets sealed to one side only.

Great surfaces and great gaskets generally do not NEED sealer, but sealer can either be used to make up for poor surface conditions, or simply as insurance. My sealer of choice is the orange or ultra-copper style of high-temp RTV from Permatex.