bore wash

[:madaz:]

i have just rebuilt and am running in my engine again and have a question about borewash and its effects on the rings/piston/bore. the reason i ask is that when i first started the car and took it for its first drive it didnt smoke any (a bit of black fuel smoke) and now that ive driven 300 odd k's its started to smoke when i put my foot on the throttle after decellerating.

when an engine is running rich (fairly excessively) during running in wat is the likelihood of the rings being glazed and then chipping etc?? is there any way of telling if the rings have been glazed? knocks/rattles or ticks that may be heard if the rings have chipped etc? and the oil smoke.
any help would be appreciated thanks.

[Mr Revhead]

did you coat the bores/rings with any product when assembling?

[sergei]

A had very similar problem on rebuilt 20v engine. I think it was combination of $60 ACL rings + stuffed injectors (not atomising). I just chucked the engine out and got a good second hand engine (off auto/face lift) for $400 about 5 years ago.

[Ae92typeX]

also could be worth asking how did you run it in?- done incorrestly can lead to the bores not beading in correctly.
Bore was also aint a good thing on any age of car

[craigt]

If the rings dont bed in you will know, you wont see the car behind you.
What do you mean by "chipping the rings"?
Did you do the guides and stem seals or just freshen the shortblock, if it smokes after decel you may have a problem there. The increase in manifold vacuum can draw oil down the guides on decel. 300 kms isnt much, what oil are you running in it? and how have you been driving it?
Did you put the rings in dry?

[:madaz:]

by 'chiping the rings' i mean the rings get so hot from the friction they chip and scratch the bore and scuf the pistons.

im running it in on 15w-40 mineral oil, taking it quite easy as its not tuned at all properly because ive changed so much during the rebuild, hardly any load, and as i said it is running rich, and i assembled the engine with 10w-40 synthetic oil.

the head has just been recoed with all new seals. could be turbo? but funny how it wasnt doing and now it is...maybe oil viscosity?

[strx7]

do you have any idea HOW rich its running? had a TRUE wide band up it?

[craigt]

Dont drive it like a pussy, go out and give it a bit of stick

[Caveman]

Give it a little load over different RPMs. a few WOT runs, rev through third somewhere safe to do so. Should help the rings seal properly.

Have you changed the oil since rebuild? might be a good idea to do so.

[:madaz:]

ok, thanks for all the feedback!! appreciated
yeah i am running it in quite easy i must admit but last time i melted a piston running in for the same reason i would this time- it isnt tuned right
so if i load it up itl just melt a piston again and because from where i am to a dyno or tuner is a long way away and expensive i thort id give it a shot running in a lil rich and be easy on it, but it still buggers up:(

ive got all the clearances from the rebuild written down somewhere but yes they are right i double checked everything when i did it!!

i had the head recoed at the same time so the stem seals should be good.

would it be possible that the turbo seals are leaking on the hot side of the turbo? its a t3/to4e bush type bearing. when i took the compressor housing off the turbo i could see a SLIGHT bit of residue behind the wheel, and a slight bit of oil in the hot side behind the exhaust wheel. There is no oil in the intake side and i have an oil breather setup and catch can which is catching a bit of oil to.

would it be possible the bore is warped for some unkown reason?? i checked all bore measurements and all was good but you never know. What gets me is that it WAS sweet when i first drove it then it started smoking. im using ross pistons and ACL race rings, and yes all the rings gaps are in the right places.

back to the turbo, would it be possible when the oil looses its viscocity to then start causing smoking problems? may explain why it wasnt smoking at the start but is now.

cheers fo the help