Massive Oil Leak, Cannot Find Where it Comes from

**kachow** · 12-08-2019, 02:33 PM

I have an oil leak spewing oil all over the entire engine bay and lost oil at around a quart per 10 miles. Thankfully I had stopped for gas and checked under the hood. I never lost oil pressure. All of the mess was on the drivers side (US 95 M3). I did a valve cover gasket and a vanos rebuilt about 3k miles ago, and I did the oil filter housing gasket, Vanos line, and Vanos solenoid gasket about 10 thousand miles ago. I found that my CCv return tube was destoryed from the bottom of the catch can, but I don't think that would be able to spew that much oil out so fast and get it all the way up to the hood. I am taking off the intake to do those gaskets to also just clean off the engine which is covered in oil. The entire underside of my car and the tail is covered as well. On my oil filter housing I cannot find a crack or a leak, and all of the bolts and gaskets were fresh and torqued down. What else is on the car that could output so much oil? Could I be leaking this much from my cam positioning sensor? Whatever is leaking would need to be high pressure for it to fly out. It covered the alternator which then sprayed it everywhere else.

Thanks in advance.

**bluptgm3** · 12-08-2019, 03:46 PM

Could be several sources.
Did you use an OE gasket and torque OFH to spec? 16 ft-lb.
Did you use new crush washer on VaNos line and torque to spec? 24 ft-lb. VaNos line is prone to leak, you may need new line.
Did you use new rubber ‘donuts’ on the valve cover bolts/nuts? These are low torque shoulder bolts. Snug is good, high torque does not increase clamp-up.

Sent from my iPhone using Tapatalk

**kachow** · 12-08-2019, 05:31 PM

I got the whole kit, new line, new crush washers, new bolts, new pressure sensor. I used an OE gasket, and just ordered a genuine BMW one. The valve cover was given all new rubber doughnuts and torqued down to spec. No oil is coming from the valve cover. All of this ran for over 1k miles before this happened. Could the camshaft position sensor spew out this much oil if the O ring failed?

**pbonsalb** · 12-08-2019, 06:18 PM

Oil pressure sender? Vanos line? Oil filter housing plug? Whatever the problem it seems live it is in the pressure part of the plumbing.

**spyderg0d** · 12-08-2019, 06:45 PM

Sure its oil? Might be power steering fluid. If its an auto it could be the trans cooler lines that blew up. If it got on the alternator, it either came from above at the vanos line, or from ahead off the fan. The only way oil gets to the fan is the cooler lines or the power steering pump or lines.

**kachow** · 12-08-2019, 07:15 PM

Oh don't worry, its oil alright. 4 quarts to be exact. PS fluid is full, and it isnt any shade of red, Trans Fluid was changed 1k miles ago. I am just trying to narrow down what it can be. I removed the oil filter housing and could not find any signs of cracking. The freeze plugs on the side of it were in good shape, and the dryest part of the filter housing, but I'll replace their rubber anyways. I'll call some shops tomorrow and see what they recommend me to do with it, and whether they have had a similar experience with another car.

**spyderg0d** · 12-08-2019, 07:58 PM

Why not just start the car and see where its leaking? If its 4 quarts its probably the filter housing. Bottom or top is either suspect i guess.

**kachow** · 12-08-2019, 10:16 PM

Sadly, I wasn't in a position to fill it back up and start it, the oil filter housing is off, once i replace the gasket, and repair the CCV, I'll know if its cracked. What I didn't know was whether there were any other places for it to leak, or if the housing cracking was an issue folks had with their E36's.

**gdavid** · 12-09-2019, 07:50 AM

A leak that bad should be very easy to find and definitely a passage under pressure in order to leak at that rate. With the oil filter housing out of the way, it will be a good opportunity to really clean that area up and make the leak easier to find.

If you are taking bets, my money is on the vanos line being defective. I just can't imagine how anything else could fail that catastrophically.

**kachow** · 12-09-2019, 10:18 AM

I'll replace that too, that seems like a more likely candidate because of how it went absolutely everywhere. All of the parts are slated to arrive Friday. Ill update the thread with what happens.