Manifold bolts

[Morris R.]

Merry christmas to all. What i can use to stop the oil from coming up from the manifold bolts. Is there anything out there that would stop this and is this normal for a corvette or for that matter any car? Thank you

[Edward J.]

Re: Manifold bolts

Morris, the two center intake bolts on each side are through bolts.You will need to take them out and clean the oil off the threads of the bolts and also the threads of the head and use some liquid teflon sealer on the threads.Cleaning the threads can be done with brake cleaner in the spray can, be warned that any cleaner of this sort wil eat the finish of the paint on engine or car. so be to use the plastic straw attached to the can that will let you direct a controled spray.

[Morris R.]

Re: Manifold bolts

Thank you edward, would it be ok to spray the brake fluid down into the holes of the manifold to clean the threads? Have a merry christmas and happy new year!

[Mike G.]

Re: Manifold bolts

Morris: I just did this using Q-tips and mineral spirits to clean the threaded holes. For a sealant, I use Permatex Aviation Form-a-Gasket. Best stuff I've found for this sort of application. Mike

[Morris R.]

Re: Manifold bolts

Thank you mike, merry christmas and a happy new year!

[Larry M.]

Re: Manifold bolts

Morris: I just did this using Q-tips and mineral spirits to clean the threaded holes. For a sealant, I use Permatex Aviation Form-a-Gasket. Best stuff I've found for this sort of application. Mike

Agree with Mike.......but I would use a doubled over pipe cleaner instead of the Q-tip. Either one will work fine, but the pipe cleaner doesn't shed like the Q-tip.

Since I'm very old school, I would probably use Permatex #2, but the Aviation sealant is probably much better. I just need to get some and try it on my next project.

Larry

EDIT: I have also used brake cleaner to clean threads like Ed stated, but if I sprayed a lot into the thread holes, I would probably change my oil after running the engine for awhile. Most brake cleaners are chlorinated hydrocarbons and can be corrosive if mixed with any moisture. No use taking any chance.

[Morris R.]

Re: Manifold bolts

Thanks larry also let me ask a question , out of ten manifold bolts only two of them are pushing oil up what do you make of this? I might add the rebuilt motor only has 1,000 miles on it. Thanks merry christmas and happy new year!

[Larry M.]

Re: Manifold bolts

Morris:

Only the center bolts are "through bolts" where the oil can wick up. So therefore there can only be four (4) that can/will leak on your intake manifold. So you are 50/50 on this. You can just do the two leakers, or you can do all four. Your choice.

I had this problem on my 1967 327/350 HP engine, but stopped the leaks by just tightening the center bolts a bit more. They were loose. HOWEVER, do not overtighten the manifold bolts or you can crack the aluminum. Just a warning.

Larry

[Morris R.]

Re: Manifold bolts

What is causing this? Will it stop after awhile from being used?

[Edward J.]

Re: Manifold bolts

Morris crank case pressure will push the oil up the center bolts.I believe the oil from the push rods drips down the sides of the cylinder head and the pressure from the crank case blow -by pushes the oil up the threads of those center bolts. this has been a problem since the V-8 chevy small block was produced. Keep in mind that a well sealed engine will look for places for the blow-by to escape. the PCV and Breather sometimes are not enough.

[Morris R.]

Re: Manifold bolts

Thanks edward

[Dick W.]

Re: Manifold bolts

Thank you edward, would it be ok to spray the brake fluid down into the holes of the manifold to clean the threads? Have a merry christmas and happy new year!

Brake cleaner, not fluid!

[Morris R.]

Re: Manifold bolts

I'm sorry mis printed thank you

[Jaime G.]

Re: Manifold bolts

Brake cleaner, not fluid!

Dick,
you are so dilligent.
Happy Holidays to you and your family.
Jaime