oil on cilinders, valve guides?
Turbo Mini Forums

Hi,

because of a problem with my new build engine i had to take the head off.

I saw that cilinder 1 was ok but no: 2 till 4 were wet with oil. The engine did smoke when it was running. I used secondhand pistons (from fastcarl) with new rings, the block was honed to clean up the bores. And the head was fitted with new valve guides.

Now i can feel some play on some valve's when there are in the valve guide. But there is only one from the inlet side that has some play and the 4 on the exhaust side.

What i want to know is if it is possible that the oil is getting from the exhaust side to the piston. At first i would say no way, but perhapse there is some kind of air circulation that makes it possible.

Of course it is a turboed engine

What are you're experiances with this?

there is nothing wrong with a A-series that a turbo can't fix.

www.turbomini.nl

As its a new build perhaps the rings need time to bed in. I'd not panic yet, and don't be too gentle so the bores glaze up.

Generally when you lift a head oil from the rocker box ends up in the cylinders. Nothing to worry about I don't think.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

thanx for the info but i now realize i forgot something.
The exhaust ports were also wet with oil.
The pistons were not a little dirty/wet but there was quite i film of oil on them

Rings need to bed in but valve's? I don't think so, AFIAK.

I was thinking then when you close the throtle a vacuum in the cilinder draws the air and oil in the cilinder from the exhaust side. Could this be what i see?

there is nothing wrong with a A-series that a turbo can't fix.

www.turbomini.nl

Are you using good quality valve stem seals on the exhausts and inlets ? The ones that use a garter spring.

Looks like oil is getting down the valves past the guides when the engine is shut down.

Also, have you inclined the engine at all to get more clearance for the turbo ? This had a tendency to allow oil puddling and prevent oil drain away from the rockers and springs which makes the problem worse. As you have the head off I'd fit the stem seals on all 8 valves and give it another go.

Richard.

Edited by turbominivanman on 17th Feb, 2011.

Minivanless, but reluctantly happy living with the decision. There'll be another one day.
http://www.youtube.com/profile?user=minimadmotorman#p/u

On 17th Feb, 2011 paneermeel said:
thanx for the info but i now realize i forgot something.
The exhaust ports were also wet with oil.
The pistons were not a little dirty/wet but there was quite i film of oil on them

Rings need to bed in but valve's? I don't think so, AFIAK.

I was thinking then when you close the throtle a vacuum in the cilinder draws the air and oil in the cilinder from the exhaust side. Could this be what i see?

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

Engine has not been tilded. I run a Mirage manifold with at T2 turbo so don't need to.

I will fit new guides with new stem seals. I will look if the they have a spring on them. I got them from Minispares so they should be ok.

@ Robert: did you change the valve guides? To prove youre theorie.

there is nothing wrong with a A-series that a turbo can't fix.

www.turbomini.nl

If you can feel the play in the guides they really need replacing. I had the same issue a few year back.

Edited by robert on 18th Feb, 2011.

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

Sounds a bit like our van. Quite smoky until it had a good lump of boost down it's throat. The head is currently with Benross, apparently the exhaust valve guides have a lot in common with a wizard's sleeve.