Lister petter engine burning oil and smoking badly, greenmech 150

[Breezeblock]

when you turn the engine over by hand does it feel like there is plenty of compression on all cylinders i would do a compression test before i condemned the piston or rings as genset steve suggested i would be inclined to look at fuel pump/injectors first also what caused the initial damage with the valve was it over revving due to fuel pump issues possibly or did it run on its own oil

[Davidmayo]

Was the new valve a good fit or was it a little slack was the valve guide In the head cracked. I think you may have the lister alpha engine with individual pumps inside the block ? Although the smoke looks blue it could be mistaken for over fueling may be worth checking the pumps are set up correctly and not over fueling at high revs. I assume the air filter is not blocked and the inlet hose not collapsing at high revs. Can u run the engine with oil filler cap removed to check back pressure.

 

when you turn the engine over by hand does it feel like there is plenty of compression on all cylinders i would do a compression test before i condemned the piston or rings as genset steve suggested i would be inclined to look at fuel pump/injectors first also what caused the initial damage with the valve was it over revving due to fuel pump issues possibly or did it run on its own oil

 

All cylinders test around 400 psi so I'm leaning toward cracked piston instead. Especially considering the rings look visually fine, although the piston doesn't look bad, especially not bad enough for that much oil to be in the cylinder. Besides I know that it is the cylinder at the front of the engine (furthest from flywheel) as this is full of oil (black wet stuff, could possibly be carbony diesel) when I take it apart whereas the others were dry. It did not run on its own, have been able to shut it off every time. If it was fuel, how would I check. When I run the engine with the injector outside it mists as it should and like I said the engine runs fine until at high revs.

[Breezeblock]

can you take the exhaust manifold off and see if there is one cylinder realy smoking if so swap inceptors or pump elements around

[PeteB]

David and I discussed this earlier today. It does sound like a fuel issue and not oil burning as compression values are good.

[Davidmayo]

David and I discussed this earlier today. It does sound like a fuel issue and not oil burning as compression values are good.

 

 

 

I have just got in from the shed after many hours and I can confirm is is defiantly oil and not fuel!

 

The problem has worsened to the point that i was winding it over, it's just about to start when it totally locked up, I removed the injector and turned the engine over

By hand to see a lot of oil pouring out the hole, I even syringes some out to make sure, the very same thick fresh oil I put in it moments before.

 

How is this happening to this extent?

[Breezeblock]

is it the correct head gasket as there may be oil ways in the gasket

[Davidmayo]

There is no oil ways though the head as I said in my original post, the oil is supplied to the rockers up through the push rods and down through the push rod tubes which run separately down the outside of the block.

the only route for oil to get from the head would be down the valve guides but I have fitted new stem seals and still got the problem so the oil must be coming up through/around the piston into the chamber.

 

All seals and gaskets I've used are genuine original parts

[Breezeblock]

is it possible the head is cracked letting oil drain into the inlet side

[Davidmayo]

is it possible the head is cracked letting oil drain into the inlet side

 

 

the injector actually passes though the intake port in the head before it then passes through head, when I removed the injector tonight there was no oil inside this port until I turned the engine and pumped oil from inside the chamber up through the injector hole. So I don't think it a cracked head.

 

I am very confused, the chamber must have been almost 1/4 full of oil or more and that's only turning over for 10 seconds or so. So whatever it is it's pretty severe. Seems odd that a piston with 400psi compression would let oil though like that doesn't it?

[njm]

the injector actually passes though the intake port in the head before it then passes through head, when I removed the injector tonight there was no oil inside this port until I turned the engine and pumped oil from inside the chamber up through the injector hole. So I don't think it a cracked head.

 

I am very confused, the chamber must have been almost 1/4 full of oil or more and that's only turning over for 10 seconds or so. So whatever it is it's pretty severe. Seems odd that a piston with 400psi compression would let oil though like that doesn't it?

 

Sounds like its pulling oil up on the firing stroke , Rings / Piston , possible the bore is glazed or washed out if that cylinder was running low compression for a time before the valve failed altogether , Compression readings would still look good due to the oil forced past the rings , As with all these things its just a guess without looking at the engine