Severe Oil Leak in the front passenger side of engine.

[michaeljchn]

Hey guys im dealing with a severe oil leak in the passenger side front on my M3.

I attached some photos. I suspected the tensioner but i have a new crush ring installed on it and torqued down when i did my vanos/chain guide service.

The leak is covering the whole front passenger side... VANOS oil canister is wet (the bottom of it at least), my steering rack boot on the passenger side, a nd behind the harmonic balancer is wet as well.

The driver side of the engine is relatively dry.

Could it be an oil filter housing gasket leak? Vanos oil line cracked? The valve cover gasket isnt leaking from the top so im ruling that out.

[michaeljchn]

Sorry im on mobile and the pictures got inserted into the middle of the post.

[cobra]

Vanos accumulator line
CPV

Mine was the same thing and I believe it was the vanos line.

[michaeljchn]

Thanks ill swap that out. But strange that im seeing it up behind the harmonic balancer also?

[eacmen]

VANOS accum and cpv wouldnt appear on balancer.

Few ideas:

VANOS gasket. Can look like a tensioner leak.

Freeze plug on the timing cover

Front main seal

[cobra]

Thanks ill swap that out. But strange that im seeing it up behind the harmonic balancer also?

It is amazing how far oil can travel but yeah that's a bit odd.

Could be the above mentioned items. I would do a thorough cleaning and then go drive it and inspect.

[michaeljchn]

VANOS accum and cpv wouldnt appear on balancer.

Few ideas:

VANOS gasket. Can look like a tensioner leak.

Freeze plug on the timing cover

Front main seal

Where would the "freeze plug" on the timing cover be located?

Im looking at real oem and im not seeing one?

Also based on this exploded view of the timing cover, i suspect its definitely the front main seal. Unless an oil pan gasket can also be to blame here as well?

[2004LSB]

If I were a betting man, I'd say its most likely the flexible, sheathed portion of the high pressure VANOS line. I had a similar issue and was chasing the leak for weeks; turned out it was a very slight fracture in the flexible portion of the line buried inside the insulation. When the engine is operating at full speed, that 1,000....1,200 PSI engine oil can find its way out and spray all over this section.

[heinzboehmer]

Where would the "freeze plug" on the timing cover be located?

Im looking at real oem and im not seeing one?

Also based on this exploded view of the timing cover, i suspect its definitely the front main seal. Unless an oil pan gasket can also be to blame here as well?

Freeze plug is on the head, behind the vanos solenoids.

I don't think it's the oil pan gasket, as there is oil above it.

When my front main seal was leaking, the oil would get onto the harmonic balancer and get flung everywhere. The entire front of my engine was coated in oil. Actually, it was so bad that I had the aux belt shift and shred itself while driving one day. If only one side of your engine is oily, then I don't think it's the front main seal. Grab a mirror and look behind the harmonic balancer, should be pretty obvious if there's a leak from that seal.

[michaeljchn]

Thanks for all your help everyone.

I'll start with the simplest and replace the vanos line as I already have the Bimmerworld line here before i tear apart the front main seal.

Will update!

[eacmen]

Where would the "freeze plug" on the timing cover be located?

Im looking at real oem and im not seeing one?

Also based on this exploded view of the timing cover, i suspect its definitely the front main seal. Unless an oil pan gasket can also be to blame here as well?

Sorry man I meant the head above the timing cover.

[chapmans]

I have this exact same leak and have been going nuts trying to figure out what it is!

So far I have replaced:
1. Valve cover gasket
2. Vanos gasket
3. Timing chain tensioner washer
4. Oil filter housing gasket

I have the front main seal on hand but I cant see any oil coming from behind the balancer when I check close up.

I'll replace that vanos line and maybe get lucky

[michaeljchn]

Hopefully for both of us its the vanos oil line loool

[WoGGo]

Thanks for all your help everyone.

I'll start with the simplest and replace the vanos line as I already have the Bimmerworld line here before i tear apart the front main seal.

Will update!

I assume this the line we're talking about 11367837614 ?

When replacing the vanos line, I imagine you need to drop the engine oil?... and anything else you need to do?

[cobra]

I assume this the line we're talking about 11367837614 ?

When replacing the vanos line, I imagine you need to drop the engine oil?... and anything else you need to do?

No draining or anything needed. Disconnect each end, remove, and replace.