Ok, first off I have a 90 GXL I just got done installing a rebuilt engine. When I go to start it up the there is a vaccum leak. I think the leak is either at the intake maniflod between the engine block and the manifold or between the upper and the lower intake manifold. I have not tested yet. I think my problem is with the gasket(s). I put them on dry. would i be able to put some silicone on the gaskets to seal the leak? When i got the engine the directions said to put the gaskets on dry, so i am thinking that it might be bad to put silicone on the gaskets.

 

I hate vacuum leaks. Did you use the metallaic lower gasket between the engine and manifold? Putting them on without silicone sealent should be enough, check your vacuum lines maybe?

 

silicone isn't going to hurt anything, just don't glop it on, you don't want it getting into the intake and restricting airflow. Make sure you odn't have a wire or old gasket material keeping you from sealing properly. Also doublecheck all vacuum lines and plugs.

PaulC

 

thanks alot i'll leak test it first thing in the morning then hopefuly seal the leak up. And be driving on no time.