Piston rings not seating

0

06cumminstea

06cumminstea
Joined
Jan 3, 2014
Messages
11
Just overhauled my 06 5.9 Cummins and after about 1800 miles the piston rings are still not seating. Installed new Valair Double disk clutch at same time, so had to take it easy for first 250 miles. This is a different block than was originally installed that is bored .020 over with PAI pistons that were coated by PolyDyn in Houston, TX. Machine shop verified that the hones in each cylinder were good. I have brand new Exergy 45% over injectors with brand new genuine Cummins feed tunes and lines. ED 63/68/14 turbo installed on 2nd Gen exhaust manifold.

Was wondering if too much fuel is washing down cylinders and causing the rings to not seat? Or is there something else I am missing here? It has a lot of black smoke idle to 1900 RPM. Missing about a pint of oil every 30 mile trip.
 
you need some better tuning if you're black smoking heavy to 1900RPM

next time, don't baby a new clutch like that at the expense of an engine!

as stated above, hook to something big and haul it hard or just start beating on the thing. full load 2nd through 6th gear, let the EGT calm down to 400 or so and go at it again... and again and again
 
Isn't it common to hone the bores if it's getting new rings? We always did that with garden tractor engines. I was told by an old fart that if you don't, there's nothing to bite the rings and help make them seat. Only 1 engine isn't running today since I learned that but that was a governor related blowup.
 
This block was purchased fully machined, but the #6 bore was to big and had to be re-sleeved and bored and honed back to .020 by another machine shop. So had the last machine shop double check the new homes on cylinders 1-5 and they were good.

OK, find a trailer with over 10k on it and pull the heck out of it?

So the too much fuel theory washing down the cylinder walls not an issue?
 
it's an issue... but black smoke isn't the end of the world, if you were gaining oil level, I'd say you had a major issue

I think you just need to seat the rings, but next time (if there is one) don't baby a new engine like that. worst thing you can do
 
So, if I do my math right, that engine is consuming 1 gallon of oil in 240 miles.
Seems quite excessive.

Mark.
 
It's like a pulling engine. Did you go get groceries a few times to break it in? NO you hooked it to a sled and let er eat.
 
first 50 miles on a street truck are kinda easy then beat it like a red headed step child. comp engine, couple heat cycles and a few burn outs then treat it worse than a old washed up asian hooker.
dont use schaffers synthetic oil for break in lol, same issues that you are having now. delo swap and rings seated after 10miles, then back to schaffers and all good
 
That oil consumption is pretty excessive. Is it obvious blowby? I've seen a couple engines that were pretty reluctant to break in- including one the mechanic finally hit with "Bon Ami"- I was freakin' over that! A small gallon every 240 miles or 5-6 hours is almost too much to be rings. Check the easier things, turbo seal, cross contamination. Could the dipstick have gotten mixed up, I've seen it before. And rediculously overfilled makes for high blowby and high oil consumption. As far as babying them, I watched Cummins run an ISX long enough to check for leaks and then the Kenworth it was in was strapped to the Dyno and flat out flogged. It was flat out GO OR BLOW.
 
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