Kingtal0n

Okay if you've been following then you know I've just completed a cam swap, burned a lobe, replaced the cam, and now I just got it back together and running with the next, new cam.

Next step.

I noted that on startup there was a decent amount of smoke pouring out the exhaust. I figured it was just running rich...

Not the case. After breaking in the cam and doing some tuning I realized that the smoke wasnt going away. it was persistant. and it was blue.

thinking to check leakdown, I did. I got 10% on Piston 1, 11% on piston 2, and 14% on piston 4. It looks like my rings have gone bad! I could hear the air coming out of my dipstick. I un-did the valves to make sure they were closed. I could hear it seeping into the crankcase.

Now im worried. Oil in the combustion chamber is BAD. But is 10-13% leakdown bad enough to pull the engine and change the rings? They have less than 600 miles on them! maybe they are still seating? They are file-fit Moly Plasmas filed to .029-.031 (for the blower). I know its wide but it never smoked before like THIS.

After driving it around a bit the smoke backed off. but its still there. I tuned it in, timed it in, played with it, re-adjusted the valves, and now Im turning my worries to the Blow-by.

Ill post some pics.

Kingtal0n

Here is a shot of the smoke after revving the motor.

RB83L69

Drive it a bit first, get a few miles on it, see how it is.

Kingtal0n

its funny you mentioned that. I was just outside today, after driving it around a bit, and i noted there isnt NEAR as much smoke coming out the exhaust.

Whats gives? Maybe while i was working on it, some oil got into the heads? very very probable, seeing as how i used the lifter valley to pour the oil into the engine on the first oil change. hmm. and also there WAS a ton of oil going everywhere when...


and what about the leakdown tests? 10-13% bad enough to pull engine to replace rings? eh..

Morley

This is going to come off stupid, but did you remember to stagger the ring gaps when they were installed? Just a thought.

Vader

King,

15% leakage is not uncommon for an engine that is considered to be in decent running condition, but slightly worn. You can always expect 5-7% leakage on a new factory engine at 5,000-8,000 miles, after is is broken in and "sealed". With cold forged pistons and large ring gaps, you should expect more.

My speculation is that your rings are not yet sealed, and the extra wide gaps aren't helping either. Considering the disassembly and reassembly, plus the fact that you have large gaps and fresh rings, I would be less concerned with the oil smoke than determining the reason your cam journal, thrust plate, and lobe got wiped out in the first place.

Kingtal0n

good points, all of them. thanks agian vader.

and morley yes I did stagger the ring gaps. somthing I did forget about however, thanks for reminding me.


and Im not quite sure why the lobe wiped out to begin with, i assume it was because of the lifter. who knows. the new cam seems to have broke in fine, so far. Im going to drive it around on the highway a little in a bit and see if it wipes out another lobe.

heh. Say, I have some videos of it running. How would I go about posting those? I assume I could just upload some to Geocities then people could download them and watch...