149 series oil consumption

"Hi!

I've using the 16v

"Hi!

I've using the 16v149 naturally aspirated on the work boat. Last time faced very high oil comsumption.
I've done the blowers full repair with change of the bearings, sealings and all gaskets.
But the problem still exists! The oil still escape and some traces of oil
comes from the exaust pipes.
What the way of escape it could be?
Any help would be greatly appreciated"

"CYL KITS,VALVE GUIDES. AVERAG

"CYL KITS,VALVE GUIDES. AVERAGE OIL CONSUMPTION FOR 16V149 IS 9.5 OUARTS PER 10 HRS.YOU MIT HAVE COLD STUCK RINGS FROM TO MUCH LOW RPM RUNING. YOU MIT TRY TIEING OFF TO A GOOD DOCK RUN UNDER LOAD FOR AWHILE ,GET IT GOOD AND HOT.WORTH A TRY"

"Usually engine runs 1500-1600

"Usually engine runs 1500-1600RPM, engine after overhauling 1000 working hours ago with full replacement of rings, valve guides, ets. Previously the oil consumption was 2 liters per 24 hours (about 2 quarters). After overhauling it was the same, progressivly rised till 20 liters per 24 hours.
Only the thing per my opinion - the piston pin retainers (were reused), but it was dubble checked for proper installation"

"Hi, I hesitate to write as I

"Hi, I hesitate to write as I don't know these engines but I thought I'd ask a couple of questions about your problem.

Does your engine have an oil cooler and could it be leaking? If it is a raw water heat exchanger, the oil could simply be exiting with the exhaust."

"The oil cooler does not have

"The oil cooler does not have leaks, checked. The cooling water clean and no any traces of oil in it.
My opinion that oil is burning due to the leakage at piston group."

"Ok, we'll rule out oil co

"Ok, we'll rule out oil cooler.

I know you said that you re-sealed the blowers but have you checked the rotor lobes for signs of oil weepage?

Did you re-kit the cylinders or just put new rings on the pistons? When you say that the piston pin retainers were checked for proper installation, do you mean that they hold a vacuum?
My experience is with the 71 and 92 series but I know that they can sometimes be very difficult to seal and hold a good vacuum on those pistons."

"The blowers are clean now as

"The blowers are clean now as just after overhauling, so no leakage there.
Only new rings, liners still in margin sizes
For the retainers - it were just sealed in place, no any tips in my 149 series service manual about the vacuum check! Only yesterday I found manual for 71 series with vacuum check tip. And also the requirement to use only new retainers."

"Yeah, I used to do quite a bi

"Yeah, I used to do quite a bit of overhaul service on the 92 series and if you don't hold your breath just right when installing those piston pin seals, they will not hold vacuum but, I'm not a 149 mech either. I ruined quite a few and never considered re-using the old ones. Not sure if that is your problem though as it sounds like they held...at least at first.

I would be inclined to think that the new rings in the old liners might be the problem. Unless you measured each hole very carefully and didn't find excess taper or out of round, I would suspect some poor ring fit and break in for at least a few cylinders. Also, if you didn't put each piston back in it's original hole, that could be an issue as they tend to take on the same wear shape as the liner.

Did you do a de-glaze and cross-hatch when you had the pistons out?"

"Jimmy, thanks your comments.

"Jimmy, thanks your comments. For the moment I think to inspect the exaust maniforld, if some of exits will be sooty more than other, I will inspect oil rings on these pistons"