Greg88

Hey Guys,

I just had my transmission rebuilt so while I had the engine dropped out of the car I figured I would change some of the problematic seals, which probably were leaking before as I noticed some oil residue on the transmission cover plate (black piece between oil pan and transmission)

I had the engine on a stand and replaced the oil pan gasket with a felpro gasket. I put a little bit of silicone on the corners of the block where the gasket meets the front of the crank and the rear of the crank seal. I then replaced the rear main seal with the Teflon felpro seal. I installed it using the provided plastic installer piece and lightly tapped the gasket into place with a 4" piece of abs.

I got the drivetrain back in place and took it for a drive. I parked the car a noticed a roughly 12" by 12" fresh oil stain on my concrete. I jacked the car up and noticed oil dripping down the oil filter from what looks like the corn of the oil pan gasket or rear main seal. and I noticed a large amount on the starter.

I really don't feel like dropping the engine again to change the rear main seal. I was thinking about just redoing the oil pan gasket on the car and see if that fixes it. I am so frusterated to see the oil leak worse then it was before!

An added note. I put the oil pan gasket on, then installed the rear main seal. I noticed I forgot to put the rear main seal gasket behind the metal piece so I had to remove the oil pan and put the seal in. Is it possible that the silicone set up prior to removing it and now there isn't a seal on the oil pan? or would it seal up again without a problem. I realize this was a dumb mistake on my behalf and I should have just redone the oil pan gasket right then and there.

Any help, ideas where to look would be greatly appreciated! Not sure if there is a "dye" of some sort to help identify the leak?

Thanks,
Greg

Chimera96

You can buy a engine oil dye kit. Comes with a blacklight and the dye shows up neon green under the blacklight.

removing pan gasket after rtv then replacing it can be done "if" you first clean off the old RTV and then apply new. I always run the bead along the whole curved front & back and up to about 1" onto where the block flattens out. Infinitely easier to do pan gasket on engine stand vs with engine in car but it can be done

The rubber pan gaskets are re-useable if you don't tear them and clean off any old rtv

Confirm the inner sleeve of the old pan gasket on the rear did not stay on that stud. It would give a gap when you put the new gasket over it and leak

clean area where it leaks and do a dye test to pinpoint source. RMS is doubtful since you put a new one in

Confirm its not the oil filter adapter gasket leaking...if its on the DS rear of the motor.

Greg88

Wow thanks a lot!

Can you explain what you mean by the inner sleeve on the old pan gasket stayed on the stud? Like just the little bit of rubber so the gasket can sit tight to the block? I'm assuming that's what you mean!?

I'll look into getting that dye and go from there!

Also the RTV goes between the block and the gasket or between the gasket and the pan?

Thanks so much!

Greg88

Also any ideas where to get the oil leak detector kit? I see some on fleabay but prices are all over the place!

Chimera96

The pan gasket has metal eyelets for each hole. "sometimes" the inner metal sleeve of that eyelet can stay on the rear stud that goes through that corner so when you put on the pan gasket it does not sit flush.

RTV goes between gasket & pan

I bought mine at Harbor Freight. I would assume a automotive supply or chain auto part store would have them in Canada. I just googled "engine oil dye kit"...and several came up. You can buy just the dye and some UV glasses and black light flash light

Greg88

Ok thanks! Well I put the RTV directly on the corners of the block. Maybe that's my problem? It's between the block and gasket.

Chimera96

Given dropping the pan with motor in the car is a tedious job....I would confirm first the source of oil leak

I have never put RTV between gasket & block, just gasket and pan

The FelPro gasket comes with 4 plastic studs you insert in the 4 corners of block to hold the gasket in place. Putting the gasket on with motor on engine stand you would not need them but they are very helpful if doing the gasket with motor in car. I put the RTV on the pan and then put the pan over the gasket (when doing it with engine in car). Use the pan bolts to hold on pan then unscrew the 4 plastic studs and use the 4 remaining corner pan bolts. Also rotate motor to #6 TDC as that positions the rods higher to allow more clearance to pull pan out.

Have only done pan gasket replace on LT1 in a B-body which required lifting front of motor up about 4 inches to get pan out. IDK about F-body but assume front frame brace is right under oil pan so some raising of motor would be needed if that is the case.

Greg88

Update new my oil leak:

I Took the engine out and had my buddy who is a licensed mechanic and builds 9 second race cars go over it. He put a new (again) oil pan gasket, rear main seal, head gaskets (Cometic .030”) and Intake gaskets on the engine. I put the engine back in my car and bang, exact same issue.

I pulled that black inspection plate off the tranny and noticed ALOT of oil coming from the oil pan gasket itself. He said he used a lot of “the right stuff” gasket sealant on most of the gaskets.

I put some dye in the oil and used that method, again. Now I notice oil laying on the head gaskets, on both sides right near the back of the heads. He seems to think that it’s wicking up there from the momentum of the car moving when I am driving it. Mind you that inspection plate is on the tranny. Which I feel would make it next to impossible to move basically directly up the engine and sit on the head gaskets.

I have the engine out now. It does not appear to be coming from the rear of the intake by anymeans. Prior to removing the engine I did clean off the oil residue on the side of the block/heads and let it run for 10-15 minutes and did not see any oil coming from the head gaskets. After driving it for about an hour it was all over the head gasket area again.


Mainly my question is, is it possible, I know “anything is possible” for oil to move directly vertical up the engine and lay on the head gaskets? I realize that the oil is probably hitting my flywheel and possibly moving up the engine easier, but it seems to be fairly sealed up. I am completely torn whether to strip the engine again and put in new head gaskets or not. He said the block and heads were true and not warped in any manner.

Any input is greatly appreciated!


Thanks,
Greg

Chimera96

Oil can get "slung" up from its leak source...but that would be slung by the flywheel and I don't see how that would get between block and bell housing and onto the back of the heads.

Oil/fluids migrate down to the lowest point

Was there any oil tracking marks on back of the flywheel? (did you see traces of slung oil from the center of the FW out towards the side?)

You did put in the hard gasket that goes between oil filter adapter and block, right?

You running PCV?

fresh oil leaking on new motor can be hard to trace source without oil dye and black light to see it. The neon green oil dye under the black light is very clear to see

If you are pushing oil out head gaskets...compression would have to be compromised

Oil on starter and back of heads/block would typically be either valve cover or intake gasket leak

Greg88

Can you explain this hard gasket that goes between the oil filter adaptor and the block? Or have any pictures.

I am running a PCV valve.

The intake and valve cover are dry. I do have dye in the oil right now and did when the car was leaking really bad. There is oil where the bellhousing and the block meet up.

Chimera96

FelPro has it in their oil filter adapter seal kit....or the dealer has it

https://www.autozone.com/gaskets/eng...231618_0_12148

It goes between block and oil filter adapter. If it was not put in, would leak pretty bad

If leak is from there I don't see how it would get slung up onto head gasket area

If you look under the car through the small rectangle slit in bellhousing you can see the rear of crank. If oil is dripping from there it is often the RMS. With the dye that would be clear to see...but you would need to pull tranny, clutch & FW to "see" if the RMS was the source or the oil migrated onto the crank from somewhere. Typically from up top like rear intake or valve cover leak but you have checked that.

The rear oil sender unit fitting leaking?? (back of manifold)

on RTV...I know people use "the right stuff"...I use Permatex Black "Ultra" RTV on intake and pan use

Greg88

I have not replaced those gaskets but I did notice that they came with the oil pan gasket kit. Maybe shoebox has a write up on that, I’ll have to look!

I have the engine out and the tranny clutch and flywheel removed. The only problem is basically the entire back of the block is wet, the cam plug, rear main seal and the oil pan gasket where it goes under the crank. And to be honest, the oil pan gasket appears to be leaking bad. It was so bad if I was driving the car anywhere the entire cabin was filling full of smoke.

The oil pressure sending unit appears to be dry. I might put the engine back in without the tranny, just bolt the flywheel back on and start it up to see where it’s leaking.

I also wanted to mention this is a 93 block LT1, not sure it has the adaptor for the oil filter

Chimera96

IDK about 93 LT1 block but assume there is some gasket between the block and oil filter adapter just like later years. My v6 Astro uses the same gasket kit. That gasket can be a bitch to get off when it has been on for several years and some people don't even notice it is there but when they leak they leak a fair amount of oil

You using a stock pan?

While motor is out I would use RTV (Black Ultra) all around the gasket between gasket & pan. You should not have to but you have a problem which is a PIA. Let it sit overnight to cure before starting motor

I also used a skim coat on both sides of the gasket that goes between the rear main seal adapter and block. You should not need to but a skim coat adds that extra sealing. You used the Teflon RMS and I know it is the "newer" type. I have always used the rubber one. If you use the Teflon one again, it installs dry, no oil.

Weird unless you have uber high crankcase pressure pushing oil out the RMS or something

At this point yeah I would start motor with tranny out but you will need to put FW on to do so. If you can't see any leak maybe pull FW back off to really see entire rear of block

Greg88

Yes I am using the stock pan.

I just took the old pan off today and the oil filter adaptor. I cleaned everything up really really good. I used Permatex oil resistant sealant on the oil pan to gasket (entire side). I noticed when text fitting it that the gasket on the RMS side is like 1/2” bigger on each side? Which I found weird. I tested fitted it on my original stock pan and it was the same. Not sure this is normal or not.

I siliconed the RMS side of the gasket to the “arch” over the seal. I did notice the seal was kind of “kinking” on the RMS. I noticed it was like this before with the other oil pan as well! Not sure if this is normal or not! See pictures

There was no seal on the oil filter adaptor. So I put one on it. Not sure how much it’ll help as I assume it’s kind of a sealed system around the oil filter?

Let me know if you see anything out of the normal!

Chimera96

without the seal between oil filter adapter and block...it will leak oil, period. You can see there "was" a seal there before....there is a outline of it on the block

Pan seal looks good