oil leak... LT1

[maroman88]

well it took 3 high mileage LT1's (140k-180k) of mine to finally experience the rear intake manifold oil leak! and boy does it leak, it was always damp but since i changed the oil the other day, the new clean thinner oil is really leakin out and from what i can see it appears to be coming from the rear of the manifold. im going to get new gaskets tomorrow, what type of sealant have u guys had good luck with?

i did some reading and obviously when placing the manifold u gotta get it right on spot on the first try, cant slide it front to back, any other tips? should be a one day job right?

[The_Bishop]

Not that big of a deal. Make sure you clean the hell out of the mating surfaces, and use 'The Right Stuff' sealer. You could also make a pair of guide bolts (Find longer bolts with the right thread, cut the heads off) to aid in dropping the manifold in the correct position.

[LTb1ow]

Not that big of a deal. Make sure you clean the hell out of the mating surfaces, and use 'The Right Stuff' sealer. You could also make a pair of guide bolts (Find longer bolts with the right thread, cut the heads off) to aid in dropping the manifold in the correct position.

The guide bolts may make it worse as the LT1 intake bolts are angled.

Just make sure you let the intake sit for a good while after you install to really let the RTV set up.

[sweetbmxrider]

I've used ultra black rtv. When you have the intake off, you should delete the egr and put on block off plates. The pipe is too close to the intake and causes the notorious leak to develop.

[maroman88]

The guide bolts may make it worse as the LT1 intake bolts are angled.

Just make sure you let the intake sit for a good while after you install to really let the RTV set up.

i think i saw let it sit for an hour before bolting it down and a full 24 to let it dry before driving

[coolmanvette75]

Just did mine yesterday. Ultra black rtv and felpro gaskets. IMO it is much easier to re install without the fuel rails attached...

[deadtrend1]

When i swapped my cam, i didn't get it right and it leaked. So i had my friend help me sit it on the second time (stood on both sides of the car) and got it since its a pain to get it under the cowl. Only took about a hour then like said, let the rtv set up. Also check to make sure its not your oil sensor leaking too.

[SupermanX24]

I've used ultra black rtv. When you have the intake off, you should delete the egr and put on block off plates. The pipe is too close to the intake and causes the notorious leak to develop.

I just moved the pipe a little further back and put some heat wrap around there to at least contain some of the heat. Car hasn't been run much so idk how good it's holding up. lol

[maroman88]

got it all apart, there was minimal sealant in the back to say the least lol
i cleaned everything nice, waiting for gaskets, since tmrws guna be cold i might polish some of the intake manifold while its off

[Slow-V6]

Does this leak down between the tranny and motor? I had the rear main seal replaced on our 95 when we had the stall converter installed and the car is still leaking. I was thinking it could be the intake gasket..

[chrisfrom nj]

the oil pressure switch looks wet could be leaking from there

[maroman88]

Does this leak down between the tranny and motor? I had the rear main seal replaced on our 95 when we had the stall converter installed and the car is still leaking. I was thinking it could be the intake gasket..

yea it leaks from the top of the block down onto every imaginable place

the oil pressure switch looks wet could be leaking from there

it was soaked but when i removed it the threads were dry, but i broke it during removal and had to buy another, picked up some thread sealant also

[sweetbmxrider]

Make sure you extend the rtv up onto the intake gaskets themselves.

[maroman88]

yeaaa it actually was on the old set a little

cleaned up the manifold a little. except the top, most of it isnt visible so i didnt bother goin all out.

[coolmanvette75]

You should paint it while ur there. And like adam said run the rtv up the head to the intake gasket. I also used gascasinch on the gaskets. You should look the proper tightening procedure too...

[maroman88]

i thought about painting it, but nahhh

this little guy
http://shbox.com/ci/intake_sequence.jpg

[Jloshotz]

Take your time on the reinstall, being careful on the lowering it straight down part. I thought SURE I did well, but I suspect it is still leaking somewhat. I'll just redo it in a month or so when I install the set of crane race golds that I've had sitting in a box since October :)

[maroman88]

got it mostly back together, cleaned up some wiring and replaced some vacuum lines. ran outa time before work so i shall finish tmrw

[The Fixer]

Looks good, and you got nice weather to get it done! Lucky!