Oil leak source

[aj_08]

Hello,

I have engine oil on the bottom of oil filter and torque converter shield, and bottom of transmission pan. Changed the rear main seal and still persists. Valve covers appear dry. Oil filter housing/ seal is dry. Drain plug is dry. I felt the oil pressure sensor after running the engine for a few minutes and that was dry too.

Oil cooler is deleted so there are no oil cooler lines. Filter is mounted vertically instead of horizontal.

Oil pan gasket is dry. However, it could possibly be leaking at the rear part of the oil pan gasket located beneath the rear main?
Or PCV? Intake gaskets??

Any ideas?

I was tinkering around and I noticed that when I started the truck, there was no oil leaking. But after idling for a few minutes a rush of oil came down the converter shield on the drivers side, then stopped. This does not appear to be an active leak.

No clue what it could be.

 

[Schurkey]

What color is the trans fluid? Burnt brown?

 

[aj_08]

What color is the trans fluid? Burnt brown

Transmission was rebuilt in January along with new transmission cooler lines. New fluid. But I'm curious about this theory because the leak is a dark brown colour. Do you think it's torque converter drain back?

Fluid in the transmission dipstick is red though. I'm pretty sure it's engine oil.

 

[WICruiser-97]

Corner of the oil pan gasket where it meets the rear main?

 

[aj_08]

Corner of the oil pan gasket where it meets the rear main?

Could be I think? I'm parked on an incline which may have an impact. Haven't seen it leak like this on level ground.

Does the y pipe and converter cover need to come off only or does the transmission need to be pulled to?

You must be registered for see images attach

 

[Schurkey]

OK. Not trans fluid.

Wash everything, blow cornstarch on the clean metal, see where the cornstarch gets wet, and where it stays dry. That should lead you to the source of the leak.

A higher-tech approach would be to dump fluorescent dye in the oil, and then use a blacklight to trace the source.

 

[aj_08]

OK. Not trans fluid.

Wash everything, blow cornstarch on the clean metal, see where the cornstarch gets wet, and where it stays dry. That should lead you to the source of the leak.

A higher-tech approach would be to dump fluorescent dye in the oil, and then use a blacklight to trace the source.

Ok will do. Would a bad oil pressure sensor cause a leak even if the sensor is dry?

 

[JeremyNH]

+1 for fluorescent dye and UV flashlight. You can get both for about $20. The flashlights take weird batteries though so order them at the same time because they're not commonly stocked in box stores. I had an oil leak I was convinced was the rear main but ended up being the not uncommon china wall at the passenger head. Wouldn't have found it without the dye and light.

 

[Schurkey]

Would a bad oil pressure sensor cause a leak even if the sensor is dry?

Sure. Who knows? Maybe the brass adapter the sensor screws into is cracked. Or loose.

 

[Texasbob]

It's a small block Chevy. They leak.