Blowby? How much is ok?

[river_clan]

I have an 86 Samurai with a 1991 hydraulic 1.6td. It is newly rebuilt, with maybe 10,000 miles on it.

Runs great, lots of power, 10lbs of boost, but the blowby is pretty crazy, and making me chase things.

I have added the crankcase vent off the side of the block into a dry-sump tank they use for race cars, and the top is plumbed to the air cleaner. The bottom of it has a petcock that allows me to drain it occasionally.

I still have lots of oil leaks, and can't find them using air pressure into the dipstick. Just lots of little leaks I guess? Do they all leak?

If I block both the valve cover vent tube, and the crankcase vent tube, it blows oil out the dipstick.

It uses/loses (?) about of a quart of oil every 1000 miles. Bottom of the motor is covered in oil.

At idle, if you take the cap off the valve cover, you can feel a lot of pressure. It lessons with more RPM's.

Do I need to re-ring it? It has lots of power, and feels as strong as ever. It's very quick. Hard to imagine that I need to do it in 10k miles!?

Help?

[vwmike]

It seems unlikely that your rings are bad already but there is always the chance they didn't seat. I would look into the oil leaks closer though.. Usually they don't leak but if they do it is often a leaky valve cover gasket. Perhaps you could try pressure washing the engine and then drive it a bit to see where the oil is coming from?

[DieselMonkey]

Use a compression tester on a warm engine on all 4 cylinders. That will give you a better idea.

Could have a head gasket mating surface problem, rings broken, rings not aligned correctly, bore(s) not honed to the correct tolerance and maybe the piston / rings expanded too much and caught in the bore and stuck the rings in the pistons' grooves. Could be a lot of things. Did you recon the injectors also ? if not, maye they where leaking, not spraying and washing the cylinder walls, which will also cause scoring and seizure of pistons. You'd have loads of smoke in this instance.

Pull the head to be sure.

DM

[935racer]

After you do a compression test follow it with a leak down test, it will let you know exactly where you are leaking from. I also agree in looking at your oil leak a little more closely, your engine shouldn't be that dirty this soon.

[Mark(The Miser)UK]

Check for true blowby by fluttering a sheet of paper over oil filler at idle then increase revs ..Sometmes the push/pull of the pistons make it seem that its blowing out of the cap when in reality its going back and forth also...