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UIM leak

2

2004GrandPrixGT1

New member
Lookin at my engine today and realized a small, maybe 10 drop, leak between the rear head and the back of the intake, no sensors sound off or CEL. I will only need to drive it for the next two days before i can fix it, maybe 75 miles. Think ill be safe? Also is the intake similiar to the old 350's with just having to take the intake and all appendages off, clean the surfaces, put the new gaskets in, lower intake, the next gaskets, then the plenum? I was also thinking to the valve covers while im at it.
 


Intake is easier than the old 350's because you don't have to worry about the distributor. You need to do the Lower intake manifold gasket.
 
Yeah, i just bought fel pro lower and valve cover gaskets. Gonna buy upper on friday with my paycheck, i was curious as to if it would be safe to drive as well. The reason i ask about the 350 is cuz i had to rebuild one for a friends 87 chevy truck and was wondering how similiar it was. Little did i know until i was loading it into the bed of his other truck it was a 1972 block. Thicker cylinder walls and 4 bolt main.
 
Do a search for LIM gasket replacement here and you will find a lot of info. As long as the felpro LIM gaskets are the aluminum frame ones then you're good. You need to put RTV in the 4 corners where the lim meets the heads. Did you get the valve cover bolt grommets w/ the cover gaskets? If not then they WILL leak again.

You also need injector o-rings.
 
I would get some, you dont want any fuel leaks.

Also buy like 10 quarts of oil. Do the job, drain it, fill with oil, run for about 15min to flush any debris and coolant out, and drain again, then new filter and oil.
 


Go for it if you want to.

Also, to me I think the whole oil leak thing is just your rear valve cover seeping out and causing the oil to pool in the intake runners.

The felpro gaskets are good, but the Alluminum ones are alot better and wont need to be changed again.

Where at in MN are you again?
 
Personally I wouldn't bother with installing the plastic LIM gaskets again. There's a reason that GM updated the design :th_winking:

And yes, change the o-rings. A fuel leak there is a bad idea as it will spray directly onto the hot LIM and manifold. Not good.
 
the rear valve cover is leaking off the back too so im replacing the valve cover gaskets as well. Fivefingerdeathpunch im located in white bear Lake MN.
 


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