j498

iTrader: (10)

2000 T/A LS1 m6
159k miles

Got an oil leak thats been driving me nuts, especially after all the time I've time and $$ I've spent tracking it down.

Background: Had oil leak which seemed like it was coming at the back of the intake. I removed the intake and installed a new OPSU, lifter valley cover gasket, knock sensor gasket, and made a custom PCV setup due to the factory version being broke in several places... Still leaked oil.

Fast forward a few weeks: Got a hold of oil safe UV dye found that the valve cover gaskets and grommets were leaking slightly. Replaced them last week and cleaned everything off near the rear of the oil pan. Ran the car for 15-20 minutes and let it cool down for over 1 hour with no drips on the ground and no signs of leakage anywhere underneath. However, it is only after cooling down quite a bit oil (a few drops) finds its way on to the ground. After degreasing the underside and looking more closely, the majority of the leak is coming from above the starter area (see the first 2 pics)


http://i69.photobucket.com/albums/i4..._724Custom.jpg

I removed the starter to see if the crank sensor was leaking but of course it cannot be that easy. I cannot tell if the oil is coming out of crank area itself or again from the back of the intake. From what I understand there is a plug in the back of the crank behind the pilot bearing that can leak, however wouldn't this throw oil all over the flywheel/pressure plate and inside the tranny area (see pic below) because it doesn't appear that way). Also, would it not also throw oil out of the drives side of the tranny where the plastic cover is?


http://i69.photobucket.com/albums/i4..._200Custom.jpg

One mistake I made when pulling the intake was not removing the cam sensor to check the o-ring, however it did not appear to be leaking anyway. I'm in the process of removing the intake again to check for leaks at the lifter valley cover again.

Anyone have suggestions on what else to check for leaks? Where else is there for oil to leak on these engines? Pretty frustrated with the whole mess.

LilJayV10

iTrader: (39)

Since you have the dye in the oil and see if you can see the oil sling from the middle of the flywheel.

nomasterase

iTrader: (4)

Check the rear cover gasket sounds exactly like what mine was doing and the previous owner did all the same stuff youre doing. It helps to run it with the trans out

j498

iTrader: (10)

From what was visible I couldn't see this with the UV light or regular flashlight. It is hard to see in there though.

I got a new clutch/flywheel installed last September. I specifically asked the garage to check the rear main and cover seals while in there so there would be no future issues, they told me there were no leaks there and the small leak I had was coming from the back of the intake area. They could be full of ****, or maybe the leak started after they did their work.

I guess I'm gonna have to get the tranny pulled out again if I don't find anything under the intake; don't feel like ruining a new clutch/flywheel setup.

I shall find out more tomorrow night.

streetknight2

iTrader: (10)

Stupid reply, be could it be from around the dip stick tube?

LS1121

iTrader: (17)

I have a small leak, most probably do. I put a piece of indoor/outdoor carpet on the floor of my garage under the car and now I have peace of mind. I no longer fret small oil leaks, water from A/C or the leak I have from my steering. I have Bigger fish to fry.

Poss17

Most likely your rear main housing cover gasket gone bad. Your leak looks just like mine, i replaced oil pan gasket, valve cover, intake. If you look inside when you removed the starter, just bend you head the right way (lol) you can see one of the bolts at the very top inside covered in oil. I replaced the rear main when i did the clutch. I had no clue that i should have replaced the cover gasket as well. Good luck!

moeZ28

iTrader: (7)

His rear cover is leaking because its been off the motor and when it was put back on, no one put rtv silicone in the bottom corners. On the front and rear covers, its common practice to put silicone in the corners where the covers bolt to the block and the oil pan to prevent leaks.

Poss17

Forgot to mention, there was no oil residue on the fly wheel. Thats the first thing i checked because i did not want to remove the tranny. If i can find a picture of my starter i will post, I swear its the same, i hope its not but if you simply cant find the leak anywhere like i did, most likely that trans is coming out

j498

iTrader: (10)

Checked there already, unfortunately its bone dry all around it.

If I wouldn't have spent a bunch of time and $ already I'd probably let it go, but now I'm determined to at least find the cause. I didn't know of the iceberg I was above to run into when starting this. Now that there is a possibility of it being my rear cover I might have someone else fix it to avoid ruining my new clutch/flywheel.

I hope not, but it may come to that.

As of today I took off the intake and found no signs of leaking near the OPSU, lifter valley cover, etc. I removed the cam sensor and it appear there might have been a little oil seeping past the oring, but it was hard to tell so I replaced the O-ring anyway.

I'll finish getting it back together over the next day or two and see if by some miracle it was the cam sensor o-ring producing the leak but I doubt it. Usually in these situations I have the worst luck/outcome possible.

I think I'm about to feel a lot of wallet pain, very soon.

Ruthless909

iTrader: (19)

Did it end up being the Rear cover gasket?


I have the same exact oil leak.



Already replaced:

- OPSU

- cam sensor

- valve cover gaskets

- Intake manifold gaskets

- valley cover gasket

- Oil pan gasket

01ssreda4

iTrader: (96)

Oil on the starter nose typically means rear main. Not uncommon with 150k.

scj

iTrader: (89)

Removing a trans/ clutch/ flywheel will not ruin the clutch and flywheel btw.

j498

iTrader: (10)

It is still leaking unfortunately, as I found out after driving it around. I'm not sure whether it's the rear cover or rear main as I don't have the facilities to pull the tranny off and check.

I might just leave it as is, I'm not sure if I wanna pay (nor am I able to) up just to have the tranny pulled just for the rear main.

Ruthless909

iTrader: (19)

I just had the rear main seal/rear cover gasket replaced Tuesday.




No more leaks!!!!

6898camaross

Rear main.

Ruthless909

iTrader: (19)

It's his Rear cover gasket.


I just had the mechanic replace my rear main aswell since the tranny was already being dropped.

Sleeper S10

iTrader: (13)

so where did the leak end up coming from?

FASTFATBOY

iTrader: (23)

Mine is leaking out of the two vent holes on each side of the bellhousing, I have had the trans out multiple times, I gave up on it. It's not that bad I can live with it.