b38 burning oil

[nsx-type-r]

Hi I have a 10 year old f22 218i that is burning oil. It asks for a litre every 500 miles. Yesterday, whilst topping it up I noticed smoke coming out from the filler.
What do you think could be wrong? Is this a common problem?

[trickywoo]

That amount is probably due to worn piston rings but there could be other problems combined.

Sometimes you can mask it a bit by going up a ‘thickness’ of oil. If you aren’t already on 5w30 you could try it but I think the amount it’s burning probably needs more detailed inspection.

[nsx-type-r]

Do you know a cheap garage i can get worn piston rings fixed for around london?

[nsx-type-r]

do you think i could use Wynns engine oil leak solution to fix this?

[RustyNissanPrairie]

I don’t know this engine but I’d be looking at any PCV system fitted. Pressure in the engine block from a clogged up crankcase vent can cause oil to be pushed up past the rings (and past camshaft and crank seals).

Check if there are any oil leaks externally and especially in the crank/camshaft areas. Remove/clean/replace the PCV system.

[DaveF-SkinnysAutos]

Another vote for checking the PCV valve first, if it's stuck open it will be recirculating oil into the intake valves and burning it off. It's a lot cheaper solution than piston rings so worth checking first.

Take your engine filler cap off and put your hand or a sheet of paper over the filler hole while the engine is running, there should be a little bit of suction but not excessive. If its blowing, or alternatively a lot of suction its likely stuck open or closed.

[nsx-type-r]

UPDATE

Yesterday, I noticed the clutch was slipping, but I hoped it was a bad dream and that it would go away. Today I broke down on the m4. It just wouldn’t engage gear. After waiting too long on the hard shoulder, I was recovered to Heston, where I was unable to drive onto the AA truck. There I noticed the car had wet itself - once it had been towed away I noticed a massive puddle of oil.

So I hope the excess oil consumption was due to the failing clutch and not the piston rings or PCV valve.

[Grenadier_45]

Assuming the engine didn't run out of oil as a consequence, I think you might have been lucky, and have your answer, but backwards. The rear main seal on the crankshaft has been leaking (oil loss), and finally gave way showering the clutch with engine oil (clutch failure).

[RustyNissanPrairie]

RustyNissanPrairie said:

I don t know this engine but I d be looking at any PCV system fitted. Pressure in the engine block from a clogged up crankcase vent can cause oil to be pushed up past the rings (and past camshaft and crank seals).

Check if there are any oil leaks externally and especially in the crank/camshaft areas. Remove/clean/replace the PCV system.

Crank seal = rear main seal. Same thing.
Don't just put a new crank seal/rear main seal in without checking the PCV otherwise you (not me!) will be playing whack-a-mole with another shaft seal on your engine

Edited by RustyNissanPrairie on Tuesday 31st March 06:50

[Dog Biscuit]

RustyNissanPrairie said:

RustyNissanPrairie said:

I don t know this engine but I d be looking at any PCV system fitted. Pressure in the engine block from a clogged up crankcase vent can cause oil to be pushed up past the rings (and past camshaft and crank seals).

Check if there are any oil leaks externally and especially in the crank/camshaft areas. Remove/clean/replace the PCV system.

Crank seal = rear main seal. Same thing.
Don't just put a new crank seal/rear main seal in without checking the PCV otherwise you (not me!) will be playing whack-a-mole with another shaft seal on your engine

Edited by RustyNissanPrairie on Tuesday 31st March 06:50

Exactly

A pressurised block will find the weakest place to exit oil from. Finding the reason for the failure is paramount