View Full Version : intake manifold gasket on a 95

08-15-11, 11:11 PM
So I've had an oil leak on my 95 that runs down the front of the block. Looks like maybe coming from intake manifold?

Anyone replace this gasket yet? how big of a job is it and any tips? THanks

08-18-11, 04:03 PM
Don't usually bump but...nobody's done this before?

08-18-11, 06:32 PM
I recently did this on my 94. Its not hard of a job at all, just time consuming. Make sure you scrape all of the old gasket off the block and intake manifold
and use brake cleaner to wipe off the oil residue. Stuff rags down into the lifter valley and intake ports so you dont get too much debris into the engine.
I punched holes into a cardboard box and stuck the intake bolts in them so I could remember where they went. Run a nice bead of RTV on the front and back
"china walls" because there are no gaskets there (I used Ultra Copper). The hardest part was setting the intake back on the block without smearing the RTV
because the intake is heavy as hell so I would have a friend help with that. Bolt the intake back down using the correct torque sequence (Search google). Also
let the car sit for at least 24 hours to let the RTV fully cure.

08-18-11, 07:25 PM
Oil go through the intake?

08-19-11, 02:14 AM
The gasket has been changed by the previous owner at 76,000 miles. Seems to be a common issue on LT1 engines.

08-19-11, 04:39 AM
I second BossHoggin, easy to do but time consuming. Having a fuel line disconnect helps so you don't have to pull the fuel rails and injectors and can bring the intake out as a whole unit. I used felpro gaskets which also included some black RTV.

csbuckn: Oil doesn't really go through it but the bottom of the intake is what keeps lifter valley sealed against the block.

08-19-11, 07:35 AM
thanks guys. I'll give it an attempt. Will have to order the parts so I'll try to take pictures whenever I do it :)

08-19-11, 07:59 AM
did they replace the seal behind the opti when they did that job?
it is super common to leak there its the dist seal , on the timing chain cover
I would look close there before jumping in to the intake

08-19-11, 08:26 AM
They said they replaced all the seals back there and I've come to trust this garage but you're right...you never can tell when you don't do the work yourself. I'll take a closer look at where the oil is leaking from before I start in on it, just to make sure.

Thanks Jim

08-19-11, 01:41 PM
Good point. LT1 intakes usually leak at the back, not the front.

08-25-11, 02:09 PM
so I've found some conflicting reports on how to install the intake manifold gaskets...some people say put RTV on both sides of the gasket, some say only the intake side, some say none at all, and only use the RTV on the front and back of the block where the intake meets.

Any input?

08-25-11, 02:23 PM
I don't think you put it on both sides, seems like it would come off and clog the intake. I would contact the gasket maker if someone here doesn't know.

08-25-11, 05:11 PM
RTV only on the front and back of the block. Not on the gaskets.

08-25-11, 06:12 PM
thanks Jay, that's what I was leaning towards.