M20B25 intake leak problem

[e30gentry]

Have an 88 325i with an intake leak. I narrowed it down to the intake manifold gaskets. replaced the gasket and still have the same leak in between cylinders 3 and 5. I tried replacing the intake manifold gaskets again and this time with some rtv and have the same leak between 3 and 5. Anyone have any idea of the chances of the head or intake getting warped in that area?

[jlevie]

That is possible, but unlikely. But with the intake off a straight edge will tell if either is warped. I don't know how you are locating the leak, but another possibility is a leak at the oil return tube or an injector seal. A smoke test will show you exactly where the leak is. Spraying carb cleaner around won't do nearly as good of a job of pinpointing the leak.

[e30gentry]

Sorry thought i stated i did a smoke test. they leak is coming from 3-5 area.

[bernzpeed]

try tightening bolts some more.

[jlevie]

Sorry thought i stated i did a smoke test. they leak is coming from 3-5 area.

The shop should have been able to be a bit more specific. Like, we saw the leak coming from the manifold gasket between 3 & 5 or top (or bottom), or there was smoke coming from the upper end of the oil return, or an injector seal or the valve cover, etc.

[e30gentry]

The shop should have been able to be a bit more specific. Like, we saw the leak coming from the manifold gasket between 3 & 5 or top (or bottom), or there was smoke coming from the upper end of the oil return, or an injector seal or the valve cover, etc.

What would be leaking at the valve cover?

[jlevie]

The gasket.

[bernzpeed]

did u clean the surface before installing new gasket?

[davem]

did u clean the surface before installing new gasket?

+1 usually there is some old gasket baked on

[e30gentry]

wizz wheeled it until it was pretty and shiny. i just smoke tested it last night and seems like there is some coming from the top of the oil return pipe and also still looks like is coming form the top of the manifold between the manifold and head. i guess i will tear it all down and do it again.

[Rigmaster]

are you 1000000% sure you got the old gaskets off? I've seen people do this and some of the gaskets stick to the manifold, and some stick to the head, they get the ones off the manifold but leave the ones (or one) on the head, then install nice new gaskets and tighten everything down, and the different spacing causes a leak.

[hamilton325i]

Wiz wheels make me nervous. I would definitely take jlevie's advice and verify the mating surfaces are level.