Holy ****, I was reading this and saw 2023 on most posts so I was surprised to see it say "Yesterday". Anyway.

I'm interested to hear what your compression numbers were during the dry tests before? I am having similar issues with a fresh rebuild (top and bottom). Prior to rebuild, compression was around 185 on all cylinders after 2.5 years of abuse. After, I'm seeing about 183, but with looser tolerances so I'm not surprised. I also knew my oil drain was kinked in places and inadequate for 6258. Fresh build I gapped rings to 0.019" as opposed to the 0.012" that the old motor had (because 12 thou is to way too tight). Now I'm experiencing what I can only consider to be a crazy amount of blowby and still have occasional puffs of smoke after high boost. Plenty of high vacuum following this will tend to clear up the residual oil and stop smoking

 

My compression numbers on the rebuilt engine dry are 149 psi. I don't know what it was before the rebuilt. I assume around 180-200?

I think your ring gap is fine. Mines 0.018. I think the issue lies with something that the machine shop did wrong on mine.

 

Ah yeah 149 does seem pretty low. Were they all around ~150 or just some of the cylinders? Any idea how fine/coarse the hone was and if the shop used a profilometer to verify correct roughness?

 

Every cylinder is 149psi. Ive got no idea what the machine shop did. (Trusted and highly recommended shop)

Im going to give them a visit soon and report back.

 

If every cylinder is low but equal, it's likely the tester and not the engine. Engines rarely fail evenly.

Many cheap compression testers are built wrong to get good numbers. A good compression tester should have the Schrader valve in the spark plug end of the adapter hose. That way only the air in the cylinder is being compressed. Cheap ones (like from Harbor Freight) have the Schrader valve in the gauge. Then you are compressing the air in the cylinder and the hoses (along with loses in the QD).

 

Yeah @Midtenn I've heard the same thing. I'd say his is accurate only if he used the same tester when he checked pre-rebuild or if he has tested on a known good motor

 

I used a brand new snap on compression tester. But I think you guys are missing the point here..... you can't have over 60psi gain when doing a wet compression test. That means the rings are leaking badly...... but for argument sake the cheap compression tester I've got read only 1 psi difference from the snap-on.

 

I mean yeah they shouldn't go up that much unless you're adding a whole lot of oil. I'm just playing devils advocate

 

After paying my mechanic to do leak down and compression tests again, it turns out my motor is fine. When I did the compression test myself I forgot to leave the throttle body open. I know rookie move. Not having the throttle body open leads to low compression numbers.

So I ended up buying a scavenge pump. I can say with over 1000km driven and many hard drives my car is fixed. No more oil leak from compressor housing. Charge pipes are bone dry and oil isn't going down on the dip stick. Im still not exactly sure what the problem is, maybe crankcase pressure or maybe my short drain just wasnt perfect enough. But atleast its fixed and I can enjoy it again.

 

Which one did you go with? I’m guessing it’s just always on?

 

I’m interested in what pump you used and how you wired it also. Sent you a pm.

 

Any feedback on what pump was used?

To test this idea in my setup, I ordered a cheap amazon pump and am currently working on a mounting system.
Mounting a pump is well, challenging. Not much room, and the pump is not tiny. I ended up making 3 pieces
which will eventually bolt together. Threw a small fan on there to keep some air flow to the pump.

View from below showing bracket and mounting plate. I need to weld more mounts on the bracket.

Pump with small cooling fan (pump is rated as intermittent duty)

A couple of videos

 

I bought a turbo werx nano pump. The turbo werx pump is self priming and very small.

Let me know how you make out with the Amazon pump