Black oil coming out from Tail pipe - Smoking like a chimney

[VinnyC]

This engine was recently rebuilt with used pistons and cyls. that were supposedly within spec. New rings were used. Once put back together and fired up - the engine smokes on idle but much worse when the throttle is applied. Its a crazy amount of smoke...enough to fill the garage.
Initially, I assumed that the rings had not seated and the smoke would disappear eventually - but that has not happened yet. I'm not driving it since the rebuild because of this.

Now i've noticed that black nasty oil spits out from the tailpipe and pools up in the tailpipe area...

Could someone please give me some ideas as to why this might be happening?
If the rings were not seated would that much oil be burned and sent out the tailpipe? Is it possible that the heads could have a bad or leaky valve in addition to the ring issue? Any help or ideas would be greatly appreciated.

[billybek]

How many hours or miles are on the engine since its overhaul?

[OldTee]

Most likely oil in the muffler hasn't had a sufficient time to burn up. Go break it in. 3-4K rpm with occasional run ups to 5K. It should stop in 30-40 miles.

[VinnyC]

Hardly any hours on the motor. I have been reluctant to drive it with the amount of smoke....

[jimbauman]

Run the engine with the car in your driveway at 2500rpm for 20 minutes ... that oughta clean it out..... then do what OldTee says....

JB

[VinnyC]

Originally Posted by jimbauman

Run the engine with the car in your driveway at 2500rpm for 20 minutes ... that oughta clean it out..... then do what OldTee says....

JB

I've tried that, and have been doing that for weeks now. No change.

[jimbauman]

Well something odd is happening (duh) ... I guess I would check:

1. the condition of the plugs - fouling? Does the engine run bad?
2. the inside of the muffler and cat converter, looking for burnt oil residue on the engine side of the cat
3. a leak down test
4. oil leaks on the tailpipe side of the engine.

JB

[Steve@Rennsport]

Dare I say it,.......is the oil level correct????

If thats the case, its time for a Leakdown test to confirm whether the rings are seating or there is a mechanical problem.

[sjf911]

Broken or improperly installed rings?
Holed piston?
Improper or worn valve guides?
Overfilled oil tank with ring blow-by pushing oil into the intake?

As above, check your spark-plugs for oil fouling. If they are clean, this should just be residual oil in your exhaust. If not, you will need to do a comprehensive diagnostic evaluation of your engine.

[john walker's workshop]

pull the muffler and have it steam cleaned. run the engine without the muffler for a while until it's hot and hopefully burns off the residual oil in the exchangers. worth a shot.

[Laneco]

Oil level first - too much and you'll suck in through the intake, if that's not it as advised above, move on to compression check.

But You know what? That sounds EXACTLY like an engine we had professionally built. Leaking, dripping, oil burning, smoking pig. A compression test (granted they are always subjective) yielded one hole at 90 pounds, the rest were about 55 to 70 pounds.

An engine autopsy proved that the pistons and barrels were a mismatch, that on several pistons, the rings were installed with the gaps ALIGNED, several of the clips at the wrist pins had not been installed, the camshafts had two different grinds, left to right, the cam towers were machined under spec, the oil pump was excessively worn, the JE pistons turned out to be Ross, and the rocker shafts had been machined past the useable point.

Other than that, it was a great engine.

So? Hate to bring up a certain dirt bag pustulous sore on the hiney of humanity - but I have a sneaking suspicion I know who did your engine build... I spent $8 grand on mine and threw most of the engine away afterward... I pray that you are more fortunate.

Professionally built my foot. Monkeys masturbating in the dark could have done a better job. If you have to do a re-do, research here. Good guys, John Walker, Henry Schmidt, Kevin Farrell, etc. Ask first and save yourself much pain and money.

angela

[Wayne 962]

I'm with Steve on this one, you need to go back to basics and run a compression check and leakdown too. Go through the steps in my article here: Pelican Technical Article: Time to Rebuild? - Part I and then see if you can gather some more clues.

If I were to take a wild guess, it would be a broken oil scrapper ring on installation. Been there, done that.

-Wayne

[Steve@Rennsport]

Originally Posted by Laneco

Oil level first - too much and you'll suck in through the intake, if that's not it as advised above, move on to compression check.

But You know what? That sounds EXACTLY like an engine we had professionally built. Leaking, dripping, oil burning, smoking pig. A compression test (granted they are always subjective) yielded one hole at 90 pounds, the rest were about 55 to 70 pounds.

An engine autopsy proved that the pistons and barrels were a mismatch, that on several pistons, the rings were installed with the gaps ALIGNED, several of the clips at the wrist pins had not been installed, the camshafts had two different grinds, left to right, the cam towers were machined under spec, the oil pump was excessively worn, the JE pistons turned out to be Ross, and the rocker shafts had been machined past the useable point.

Other than that, it was a great engine.

Hmmmmmm,..sounds suspiciously like an "engine of ill repute",....

Based on what I've witnessed, I can bet heavily on who did that one.

[cstreit]

Originally Posted by Steve@Rennsport

Hmmmmmm,..sounds suspiciously like an "engine of ill repute",....

Based on what I've witnessed, I can bet heavily on who did that one.

I've got dibs on a certain company on the West Coast!

SSteve is spot on (not shocking news here), eliminate major issues by doing a compression and leakdown test. Post the results here. Look at the plugs, is there oil on them? Check in the intake, is there oil in it?

[JFairman]

After trying the other things mentioned you can do your break in driving at night so the smoke is harder to see and not so embarresing.