[barlowrs]

Update 6/12/2024:

I completed the leakdown test hoping it would solve the mystery and tell my oil rings are bad, or my rod seal it shot, unfortunately, all it did was tell my the engine is good (Which I am very happy about, but I want to know where all the oil is going!!). Below are the leakdown numbers, so, given this, I am at a loss, what do I look at next?!

1: 2%
5: 1%
3: 2%
6: 2%
2: 3%
4: 3%


************************************************** ************************************************** ************************************************** ************************************************** *************



Hey Everyone, New here, I am hoping all your brains can help me figure out a problem.

I have a 03 E46 M3, with about 190K miles, however, the engine was totally rebuilt about 15k miles ago. She is also supercharged with a VF570 kit. I am having a pretty severe oil consumption issue (consuming about a quart every 250-300 miles). Besides the smoke and having to add oil all the time, she runs STRONG. Here are a few facts and troubleshooting I have done:

Under heavy acceleration, I do have smoke coming out of exhaust, so I think it is burning some oil. However, based on investigation (see below), I think I'm actually burning oil, AND leaking oil, two sperate issues. Problem is, I cannot be sure how much each issue contributes, so for example, if it's only burning a bit, a catch can will probably fix that (however, when I get on it, it's a LOT of smoke).

So, for this thread, I will break down my findings in two categories, internal (burning) and external (leaking):

Internal:
1. My biggest fear is rings or head gasket (all were brand new when engine was rebuilt, but anything is possible. I did a compression check and compression on all cylinders is 170-175, so I do not think its rings or head gasket. I will probably do a leak down test later just to be 100% sure, but with those compression readings, I doubt it.
2. I do NOT have a catch can on her yet, with her being supercharged (pushing about 6psi boost), I figure I should add one. This may help, and if I'm only burning a little, may solve the problem completely, BUT, is there anything else anyone thinks I should check?

External Leak:
1. I have never seen oil on the ground, so I figured my oil consumption was all internal, however I finally jacked her up and puled the belly pans off and sure enough there was oil there. Not enough to account for a quart every few hundred miles, but that is just sitting in the driveway. I am thinking that when she is driving and under pressure (especially since I am boosted), it leaks more. When I roll my windows down, I do smell oil, so I assuming that is oil leaking onto the exhaust manifolds.
2. When trying to trace the oil I saw it in two spots, 1, SLIGHT weeping on the oil filter. I'm assuming the gasket, but is barely weeping, so definitely not my issue. the other was on the passengers side dripping down the rear of the engine around the constant pressure valve area.
3. When I saw oil in this area, first instinct is CPV (even though it was just replaced with viton o-rings). I pulled it anyway to see, and the o-ring was pristine, so it is not the problem (I put a new o-ring on again when re-installing it)
4. All other common leak areas were replaced as well with the rebuild, CCV, valve cover gasket, etc, so I cannot rule them out, but hopefully there is something else I am missing and they are fine. Is there a good way to check CCV rather than just replace it and cross my fingers?
5. I did try to get an inspection mirror behind the engine and THINK I may have seen some oil weeping out what I assume is the valve cover gasket (see image)


6. I do see oil coming out of what looks like the junction between the motor and the transmission (see image)




Part of me is wondering if the boost is causing the crank case to pressurize and forcing oil out the seals, but if that was the case, I do not understand how I am also burning oil as I would image the blow-by causing the crankcase to pressurize wouldn't allow oil in the cylinders.

So at this point, I am thinking valve cover gasket (based on first
pic above) or something between the tranny and engine.....what am I missing? what else can I do to help isolate either my oil burning or my oil leaking issue? 10W-60 is expensive!

[mapster37]

May be a good idea to do a leakdown test.
What was done when engine was "rebuilt"? Pistons, rings, etc?

[AbuArije5]

Man tough to say

[barlowrs]

Originally Posted by mapster37

May be a good idea to do a leakdown test.
What was done when engine was "rebuilt"? Pistons, rings, etc?

Rebuild Included:

• Lang Racing CP Pistons
• XP Tri-metal Racing Bearing Set
• Complete Head dissasembly, inspection, pressure check
• High Performance 5 Angle Valve job
• New Valve Seals
• Trueness check (resurface if needed, but dont think mine needed)
• Bore and Hone block to 87.25mm
• Surface Block Deck
• Hot Tank and Clean
• All new bolts (crankshaft, head, bearing cap, cam bolts, etc)
• Beisan System Tensioning Rail
• CPV with Viton O-ring Upgrade
• New Oil Pump and Timing Chain
• New BMW Oil Pupmp
  
• Block Complete Teardown and inspection (main bearing clearance, rod bearing clearing, balancing piston and rod, Piston to Bore clearance, Piston Ring Gap,
• Valve Shim Clearance
• VANOS Unit
• Valve cover and oil pan gaskets
  
• S54 Widened Rod Bearing Kit (crankshaft modified for wider journal)
• Carillio Rods
  
• Cylinder Head Gasket Set
• Crankcase Gasket Set
• Beisan Systems Plate Seal Kit
• Beisan Systems VANOS Oil Pump Hub Disc
• Beisan Systems Anti Rattle it
• Fluidyne Oil Cooler/hoses

[mapster37]

Pretty extensive rebuild. I would bring it back to the shop that did all of that work. I'm sure it wasn't cheap...

[barlowrs]

I completed the leakdown test hoping it would solve the mystery and tell my oil rings are bad, or my rod seal it shot, unfortunately, all it did was tell my the engine is good (Which I am very happy about, but I want to know where all the oil is going!!). Below are the leakdown numbers, so, given this, I am at a loss, what do I look at next?!

1: 2%
5: 1%
3: 2%
6: 2%
2: 3%
4: 3%