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Sudden massive oil leak.

371 Views 13 Replies 8 Participants Last post by  Sapote
Suddenly the M54 on my 325i decided to spew all the oil out all over the engine. Had it towed home, added 2 quarts and drove it 30 feet into the garage. Drove fine, no engine noise. Tried to locate the source, but have not been able to yet.

Four years ago the CCV system, oil line, oil filter housing gasket, and dipstick O ring were replaced with OEM parts. Did an oil and filter change last week. Filter O ring was installed correctly and properly seated an torqued. Drain pan bolt and gasket was good as well. Has anyone had this issue before, if so, what caused your issue?

I appreciate any feedback, and any ideas as to what this massive oil leak could have been caused by?
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Impossible task. "Deduce where my oil is leaking from." The only thing we get to know is its an engine.

My suggestion is to get a bright light, confirm the oil level is proper, start it up and watch for oil leaking. As described it sounds like the leak will be very obvious!
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Suddenly the M54 on my 325i decided to spew all the oil out all over the engine.
I want to see the pic as it can help us to locate the leaking source.
Filter O ring was installed correctly and properly seated an torqued.
I thought I had done mine properly in fact I was utterly convinced I had, until someone pointed out the nipped O ring at the back of the filter housing. :(
Might be worth another look ?

Mart.
Sudden and massive?
How did you know while driving?
Underbelly tray will catch oil and prevent from getting to the ground
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Sudden, massive oil spill
All over the engine ....so not dropping from below.

Sounds like oil under oil pressure.
Since you recently did an oil and filter change, I'd be looking there.

you may have to run engine and look to find it.
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3


There were no indications while driving, then again didn't drive it very far to the store. Parked it, walking to store, clerk said car is leaking. Got back to find a puddle underneath. Opened the hood, front of the car was covered, expansion tank, rad hoses, belts, pulleys, alternator, top of rad, etc.
Checked the level, nothing there. Next day checked filter torque and O ring, no issues. Drain lug, no leaks. Added 2 more quarts, not obvious leaks underneath, level still at 4 quarts to day. Only issue I found so far is the plastic locking ring on the CCV hose from the VC to the Can is cracked, but both ends of the hose were still attached.

Considering the way the oil splashed everywhere its going to be pressure side leak. Only way to find it at this point would be to reinstall only whats required to get it running, (i.e no belts, no alternator etc.) and see what happens. I don't think it will need to run for very long before the leak shows up. Any other precaution I need to take before

starting it up like this?

The attached images may help to locate it.
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There are minimal spots oil can come from that side/that far up

-OFH gasket - maybe got pinched/shifted/broke during install
-Vanos line/washers/banjo
-Pressure switch
-Temp switch
-Oil filter cap o-ring
-If the CCV hose was broken off, youd see it coming out of the end; a cracked clip ring shouldn't effect the seal if its seated (sounds like it is)

I'd clean it up good and have someone turn it over a few times/let it run for a couple seconds while you watch that area. the pressure builds quickly enough you should spot it fast
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There are minimal spots oil can come from that side/that far up

-OFH gasket - maybe got pinched/shifted/broke during install
-Vanos line/washers/banjo
-Pressure switch
-Temp switch
-Oil filter cap o-ring
-If the CCV hose was broken off, youd see it coming out of the end; a cracked clip ring shouldn't effect the seal if its seated (sounds like it is)

I'd clean it up good and have someone turn it over a few times/let it run for a couple seconds while you watch that area. the pressure builds quickly enough you should spot it fast
plus 1 on this.

I suggest you wear a tyvek suit and some eye protection...
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When I went back to car to see what was leaking a puddle had formed under the engine and was running out under and just in front of the left wheel. The splash shield and reinfocement plate were cover in oil. I'll try turning it over and see what happens. Thanks for the input.
Might pull the under tray to see better. You need to clean it anyhow..
OFH gasket - maybe got pinched/shifted/broke during install
It cannot spay oil on top of the coolant hose.
Opened the hood, front of the car was covered, expansion tank, rad hoses, belts, pulleys, alternator, top of rad, etc.
I think the filter cap O-ring leaking. If the o-ring is not in the cap groove but mistakenly installed against the cap base, then the oil thin oil at high rpm can spray out. If not, then I think the vanos oil line banjo leaking.
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