Yanmar 4JH110 Excessive oil consumption / black smoke

[ArranP]

Yanmar 4JH110 Is consuming 5 litres of engine oil for every 12 hours of running, black smoke over 1500 rpm and load jumps from 43% to 100%.

All 4 cylinders have been compression tested with readings 350 to 400 psi inline with manufacturer recommendations.

What should be checked replaced next ? head gasket ?

[Renegde_Sailor]

Sounds like your valve guide seals on the exhaust are going bad, also check the crank case breather.



If the engine has good compression it is not the head gasket.

[skipperpete]

Originally Posted by ArranP

Yanmar 4JH110 Is consuming 5 litres of engine oil for every 12 hours of running, black smoke over 1500 rpm and load jumps from 43% to 100%.



All 4 cylinders have been compression tested with readings 350 to 400 psi inline with manufacturer recommendations.



What should be checked replaced next ? head gasket ?

Well it sounds like a seized turbo but you should be getting fault codes like low boost etc , are these showing up on the screen. Leaking turbo seals could explain the oil consumption. Can you manually spin the compressor/turbo shaft?

[neilpride]

Turbo shaft seals maybe? Easy to check.

[bstreep]

What Neil said. Sounds like a turbo problem, in any case.

[ArranP]

Turbo shaft was buckled 9n both ends, swapped it out with one from port engine.

There wad a lot of engine oil inside the air ducting from the exhaust outlets through the intercooler back into the turbo.

Black smoke still appearing over 1500 rpm, although transmission is currently dropping out if gear so will replace transmission fluid and try again. Still lots of black smoke and oil coming out from the turbo or air ducts.

Could it be the engine oil inside the air ducts has caused the turbo shaft to buckle?

Im not getting the jump from 43% to 100% load now that the turbo has been swapped out.

[skipperpete]

I’m not real clear on what you mean by “ buckled 9n both ends” and “swapped it out”. Either way, a turbo runs at ultra high speed so a bent ANYTHING is a death sentence for it. I guess the 4JH110 has an intercooler so hell yeah its going to be full of oil, probably blocked and easily the cause of black smoke and the source of any number of fault codes and other problems. What fault codes are you seeing???
And I’m interested in whats going on with the gearbox, sail drive, dock n go or Kanzaki hydraulic?

[ArranP]

Originally Posted by skipperpete

I’m not real clear on what you mean by “ buckled 9n both ends” and “swapped it out”. Either way, a turbo runs at ultra high speed so a bent ANYTHING is a death sentence for it. I guess the 4JH110 has an intercooler so hell yeah its going to be full of oil, probably blocked and easily the cause of black smoke and the source of any number of fault codes and other problems. What fault codes are you seeing???

The shaft of the turbo is buckled, it is no longer straight, is spinning off axis and worn the outer edges of the blades to one side at both ends.

There are no DTCs.

The service manual specifies a compression of 464 +/- 14.5 psi. In my compression tests i got 350 to 400, does this mean i got blow by and pressure in the crank case that is therefore the cause of excessive engine oil within the air ducts, turbo and intercooler ? Or might there be some other checks / tests to conduct before concluding the engine needs a rebuild.

[neilpride]

If you have the intercooler full of oil you need a new turbo, I would not buy a rebuilt one, and then you would have to disassemble the intercooler and have to clean the whole intake system.

Beware of engine runaway.

[ArranP]

I have the C35 engine panel, it has an oil pressure gauge. Question, if there is blow by pressurising the crank case, would it not show on this oil pressure gauge? My oil pressure stays at a constant 50 or so psi right up until there is no oil left.

[neilpride]

Originally Posted by ArranP

I have the C35 engine panel, it has an oil pressure gauge. Question, if there is blow by pressurising the crank case, would it not show on this oil pressure gauge? My oil pressure stays at a constant 50 or so psi right up until there is no oil left.

You mentioned that all 4 cylinders are in tolerances, difficult to blow by the crankcase, but you can check that too.

I don't know if your yanmar has a PCV valve breather on the rocker cover, but equally, if the oil cooler is flooded with oil, it's not coming from there.

On my old perkins with many many hours of use, it started to leak oil through the oil filter, but they were drops from time to time, probably low in compression, but you didn't notice it.

[ArranP]

I did not clean the air ducts, intercooler or exhaust manifold of oil. I think I should try measuring the crank case pressure from the oil filler cap with a tube filled with water and calibrated in inches first, and then try swapping out the air ducts, intercooler and exhaust manifold from the other engine to see if there is any effect.

It could be that the exhaust is still clogged up with oil.

[skipperpete]

This is making no sense to me at all, 3 catastrophic failure scenarios across 4 posts on a common rail engine, now would be a good time to un can the oil filter paper element and inspect it for metal because running an engine out of oil to zero psi ranks as a damaging event. Not to mention the turbo and gearbox problems
Good luck with it ArranP, I hope this has a happy ending.

[rslifkin]

I'd definitely try to clean the oil out of everything as best you can. It's quite likely the engine is significantly carboned up from the oil consumption and lack of turbo boost. So now that it's making proper boost and not sucking down huge quantities of oil, it likely needs a good, hard run to burn out the carbon. And it will likely be pretty smoky under load for the first bit, then start to clear up.