weird oil leak

[matt j]

Hi guys got kind of a weird situation. I rebuilt an ej22t motor new bearings new pistons new rings all factory. Anyway the car runs really well but I have a nasty oil leak that I just can't pin point. Not only is it dripping on the ground but its also pooling on top of the motor as well. I have checked the oil galley plugs and they are tight I have checked the head gaskets and they are to spec. It drips down the passenger side on the cross member and also dripping onto the exhaust. I lose about a 1/4 court every time I drive the car. Its only got 100 miles on the motor. Any help would be greatly appreciated

[mike-tracy]

OK so I'm pretty sure I did the same thing. Basically the head gaskets are the same backwards and forwards, bore wise and water-jacket wise, except for the top front oil galley ring. It would pour oil out on top of the block and get everywhere.

So after I had a friend start the engine I could easily see the oil pooling from there. Hope that's not your issue, but a brand new head gasket fixed my problem 20k miles ago, and haven't had an issue since.

[cj91legss]

As far as the drip down the passenger side, there's a cam cap on the back of the passenger head that usually has problems. It's just an O ring about 1.5-1.75" in diameter but there are also 2 smaller O rings both on top and on bottom of this cap that are for the coolant lines. it's right between the turbo and head.

[matt j]

well as far as the headgaskets go, i did that the first time around haha, so bought a new set of headgaskets and slapped them in. i lost a ton of oil from that. This one only starts to pool badly after driving it seems. I just got done cleaning the snot out of the motor and i have dye in the oil (my oil is now a opaque type color) and with a uv i cant really see anything from the top side, its weird i have oil sitting on top of the bolt that holds the alternator bracket down, and looks like possibility of a small leak from the top of the oil pump. Its very frustrating since ive been building this motor for the last 4 monthes

[PhyrraM]

The oil pressure switch is known to fail and leak occasionally.

[matt j]

Well after searching around i found the breather vent under the intake manifold was extremely loose like i pulled on the hose (which wasnt attatched to anything) and the elbow popped right out. So im hoping thats all the problem was.

[cj91legss]

Are you talking about the tube under the "F" pipe or the tube behind the alternator? Either way, yes those will cause a pretty nasty leak. My girlfriend's 93 ss didn't have a clamp on the hose under the "F" pipe and it was nasty there.

[matt j]

well see my motor is in a 98 impreza RS. The breather setup was non existant when i originally got the car so never had a clue what it shouldve been. The one behind the alternator was completely open, and for some reason i was able to pull the elbow out of the block with ease, it just slid out and that doesnt seem right to me? i put some anarobic sealant on it to try and seal it but not to sure if it will.

[matt j]

well put in a new breather setup, and found that my feed bolt was just a bit on the short side. Still leaking oil though. The top of the motor is now dry but its dripping off the crossmember. The back side of the head looks good, will leave a spot the size of a softball on the driveway, and sometimes are multiple drips.

[cj91legss]

Most likely you will have to jack the car up and get under there with a flash light. Hope for the best but expect the worse. Could be the oil return line below the turbo, Hell if the breather line was loose on top of the block, maybe the oil line is loose on the back of the head, although you say the head is clear. as far as what is leaking could be something on the bottom of the head or worst case rear main seal and that access plate could be leaking. Did you replace the rear main and seal up that cover plate behind the flywheel/flexplate?

[matt j]

rear main seal was replaced, and i used anarobic sealant around the plate behind the flywheel. Here are some pictures that i took while under the car.













Yes i am running the turbo on oil only currently and no coolant. Just letting the car cool off for a little bit before shutting off. As you can see the underneath of the cross member is disgusting.

[cj91legss]

Wow that is a lot of oil. It's really tough to say. You sealed the block halves with sealant too? there are also allen bolt plugs under the heads, did you check those? I'm running out of ideas if you just replaced everything. Did you tap the rear main seal in too far or just flush with the crank?

[matt j]

well i think we've narrowed it down a bit to the rear main or the seperater plate. The story behind the motor is i bought it from a guy that rebuilt it in his college automotive engine building class. he put new oem subaru bearings in it clearanced them and everything and reassembled the short block using new gaskets. He put in non turbo pistons wanting to raise the compression with boost. About a year after he rebuilt the motor he was diagnosed as legally blind and could no longer work on cars or drive a car, so the motor sat on a stand for 3 years until i got ahold of it. I removed the non turbo pistons and installed new oem subaru turbo pistons and new rings. i reused the heads off my old ej22t motor that i spun a rod bearing in that werent leaking at all, i cleaned them up and mounted to this block. and thats basically where we are at today.

So in short i did not install the rear main seal, I didnt inspect where the seal was sitting on the crank, when i replaced the plates behind the flywheel i used anarobic sealant but maybe that didnt seal. It is no longer smelling like burnt oil to much anymore. Just after an occasional romp on it.

[cj91legss]

In some of the photos it also looks like there is water down there, do you have a coolant leak as well or did you drive in the rain?

[matt j]

there were a few water puddles that i had driven through

[Legacy777]

I'd take some degreaser and a power washer and clean the oil off. Once you do that, it should be easier to narrow down where it's coming from.

[matt j]

Motor is out, and result is that it was the rear main seal, its pushed in considerably far, so going to get a pick tomorrow from work to fish out the old seal. New one arrived today. Also already installed the new throw out bearing and clips. Here are some pics


Noticed this while i was pulling the motor too

Motor out again





So verdict is its the rear main obviously, also the torn oil return line, so going to replace that while the motor is out and easily accessible. and going to reclean the hell out of everything!

[Legacy777]

Did the previous owner redo the oil separator? If so, I might suggest doing that again incase they didn't do it right. It's easy to do now vs. having to pull the motor or drop the trans again in the future.