Rings for KB pistons 4.080

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crewchief

crewchief

A & P Mechanic
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Had a discouraging break-in this year, too much oil consumption and burning. Engine work done by a reputable machine shop, boring and hone completed properly. New seals were used from Comp spring kit (deflector type seals). Leak down was conducted and results were on average 6%-10%.

Looking into better rings for Keith Black KB243-040 Hypereutectic Flat Top pistons 4.080 bore require 5/64, 5/64, 3/16? The Seal Power ones just didn't break in well (1500 miles), too much oil consumption and burn.

I've heard that Total Seal rings are the better ones to use. This is not used for racing motor just street/strip. Any advise would be helpful?
 
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If the cyl were honed properly for the type of rings you have...?..... then i would be looking elsewhere for your oil consumption!

Like the intake gasket......if it didn't seal on the underside, it could be sucking up oil from the valley of the eng.
Have you pulled the plugs and compared then to each other? are they all oily? just one or two..............that should get you started down the Right Path.
 
The intake was found warped and was corrected by machining. That didn't resolve the consumption. In fact it, it began to burn oil out the left side. Found #3 to be wet and all others were not looking as bad (slight tan on the tips, dark otherwise). Block work was done by a reputable machine shop. They had all rotating assemblies for balancing and knew I was using Sealed Power E-286K40 rings.
That's why I'm leaning towards a re-hone and better rings. Heads had valve job performed, just replaced springs (901-16) to match the Comp Cam CL20-210-2 and installed the supplied seals.
 
Ask the shop what piston-to-bore clearance was used. Or, if it apart, check it yourself. Those rings should be fine if all else is right. Never have had a ring seal problem of any type with moly top ring sets like the Sealed Power ones in a coupla dozen assemblies.

Was the break-in with synthetic oil perchance?

I think I am in the minority but the Total Seal rings I used once in a rally car 4 cylinder engine wore the bores a lot faster; the ring tension is a lot higher, and so is drag in the bores. So I don't use them anymore. And if you don't use torque plates on the block when boring and honing for them, I suspect you lose a lot of the benefit anyway.
 
Break-in was with Lucas break-in oil, had to use high zinc due to flat tappet cam. I thought that oil consumption from the beginning was because of the intake. That being fixed at 1200 miles now just made the smoke more noticeable than before and consumption continued.
Motor is still together, haven't decided on avenue to take yet. My thought of burning out the left pipe is that the #3 second ring could be upside down.
Because teardown is necessary, I will have it honed and install fresh rings. Just not sure if I want to use Seal Power rings again.
 
The only rings that i have had ANY PROBLEM WITH were a set for Chrome rings! But there was NEVER, a problem with oil consumption.............

Your rings may not be sealing but you should rule out everything else first in my book............
 
PCV system is working fine. Closed off left and right valve cover ports and placed vacuum gauge on dipstick tube and found a very slight positive reading. I'm thinking that the plugs are telling the story. With new seals and valve job done, intake repaired, just not sure what else it could be.
 
crewchief said:
Break-in was with Lucas break-in oil, had to use high zinc due to flat tappet cam. I thought that oil consumption from the beginning was because of the intake. That being fixed at 1200 miles now just made the smoke more noticeable than before and consumption continued.
Motor is still together, haven't decided on avenue to take yet. My thought of burning out the left pipe is that the #3 second ring could be upside down.
Because teardown is necessary, I will have it honed and install fresh rings. Just not sure if I want to use Seal Power rings again.
Click to expand...
I'm not trying to be a asss here but come on!
You had a oil consumption that was from a poorly fitting intake manifold. fixed the problem??????? and your oil consumption did NOT improve...........
Re remove the manifold, lightly grease the gasket surface and install.........when you remove it. you will see the problem(clean both gasket surfaces completely First of course)

OIL CONSUMPTION!
Rings ...yes
Intake/Valley...yes
Crack in intake...yes
Crack in intake port in the valley area...yes
The only other place i can think of that you could get oil consumption is if you were pouring it in directly down the carb yourself.

I think you need to invest in a new manifold instead of complete disassembly of short block, new ring, $, hone $$ re hot tank$ cleaning out all the oil ports back out with round brushes. Giving it one more bath, re/replacing all the plug and freeze plugs, completely reassembling short block Exc exc.

One more thought. if you had your head ported, there could be a thin spot just after the push rod area where oil could be pulling oil in thru that crack......ask me how i know this:(

If the heads were shaved, work with the manifold you have.
If not a new/different manifold may be your best bet.
 
Yup forgot about the PVC!
Plug it off at the carb.(will cause eng to run poorly at idle) and drive it. if consumption goes away problem solve.
still think its your manifold.
 
Intake removal was initial thought for consumption. When removed, it revealed 7 of 8 had wet intake galleys on the heads. Heads were not ported and manifold was magnafluxed by my NDI shop prior to machine work.
I did drive it with PCV disconnected and plugged at carb...no change in burn.
It still doesn't explain why blue smoke appears out the left dual only, real noticeable when decelerating.
 
In other works.......the oil is being pulled in under vacuum. the piston is under Vacuum "every" intake stroke........where is the vacuum at when the throttle is closed?
 
crewchief said:
I did drive it with PCV disconnected and plugged at carb...no change in burn. It still doesn't explain why blue smoke appears out the left dual only, real noticeable when decelerating.
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Oil smoke under deceleration sure says intake (or something connected to the intake tract). With that #3 plug oiled, that symptom sure ought to help zero in on it. Still could be a valve stem or seal.... you can't rule out a mistake in the head work until it is checked for sure. Is the #3 plug still oiled after the intake R&R?

With a ring oiling, you'll typically see that all the time cruising or under power of any level. FWIW, the 2nd ring does appear to have an 'up' direction per the FM site.
 
nm9stheham said:
Oil smoke under deceleration sure says intake (or something connected to the intake tract). With that #3 plug oiled, that symptom sure ought to help zero in on it. Still could be a valve stem or seal.... you can't rule out a mistake in the head work until it is checked for sure. Is the #3 plug still oiled after the intake R&R?

With a ring oiling, you'll typically see that all the time cruising or under power of any level. FWIW, the 2nd ring does appear to have an 'up' direction per the FM site.
Click to expand...
I'll be pulling the intake yet again to inspect the gaskets and intake galleys. That damn left side smoke still has me puzzled. The #3 plug was wet prior to intake mill work and after reinstall. She smokes at idle as well as down the road. I had someone following in a second vehicle and they have noticed smoke during cruising and during slowdown. But just out the left pipe.
 
crewchief said:
I'll be pulling the intake yet again to inspect the gaskets and intake galleys. That damn left side smoke still has me puzzled. The #3 plug was wet prior to intake mill work and after reinstall. She smokes at idle as well as down the road. I had someone following in a second vehicle and they have noticed smoke during cruising and during slowdown. But just out the left pipe.
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OK.... having someone else observe is the best way to do it. Does it smoke when accelerating? These questions have to do with the vacuum level; decel is the highest vacuum, and cruise can be fairly high and idle can be 10"-15" or even much more, depending on cam. So if the smoke is strongest for decel, and middling during cruise and idle, and just about gone under acceleration, then the smoke is in proportion to higher intake vacuum levels and that points to the intake tract.

If it is there under acceleration too, then I'd think of a ring problem. I personally would pull just that one. BTDT with an improperly installed oil ring expander on one cylinder.

Don't forget to look at the #3 valve stem seal and valve guide.
 
I would agree with the intake tract. It does on accelerating but not as much as idle and deceleration. Because of one side, I'm thinking I screwed up on one oil ring too.
 
If intake is tight (no leakage into the heads), can only one cylinder having a second ring installed upside down, cause that cylinder to reveal smoke at idle, cruise, and deceleration?
 
Sure... The 2nd ring is a possibility since it serves also to scrape oil off the cylinder walls, and, per the FM illustrations, the 2nd ring has a definite 'top' side. If upside down, it won't scrape the oil off properly. There is a bevel on the inner circumference, and that bevel should normally be down.

Sealed Power Premium Piston Ring Set

Or the oil ring has a problem.... perhaps in the expander. The oil wetness on #3 plug is certainly saying it is right there in that cylinder or intact runner area. You ought to be able to run this down without a full tearing down.
 
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If it turns out that it is the #3 piston is the issue, than it will require a complete disassemble. Re-hone the block and install new rings, is my guess.
 
If you're going to pull the motor apart. The first thing to do is pull the intake. Take it apart VERY slowly and look for tattletale signs in the intake track as well as the gasket.
IF it is rings.....the intake track will be dry.
 
crewchief said:
If it turns out that it is the #3 piston is the issue, than it will require a complete disassemble. Re-hone the block and install new rings, is my guess.
Click to expand...
You can pull the head drop the pan and pull #3. Done this before. Nothing special, just sometimes awkward to pull the pan. But saves a ton of time.

If the ring expander has a problem no need to rehone IMHO; pop in a new oil ring and keep the existing top and 2nd rings.

Even if #2 ring was flipped, I'd be tempted to just install a new one and go, if I did not have too many miles on the motor. And not hard to hone in place if it needed it.
 
Thanks for all the valuable input. It's been put in storage for the winter now. Come spring, I'll pull the intake and look at the gaskets again and check for wet tracts. If dry, then I'll move onto the rings and replace the seals again.
Update in six months.
 
Like mentioned previously check valve seals. I had a positive seal ride up and it would smoke on decel.
 
Rings are never the problem, unless it's an assembly error which isn't the rings, but the hands...lol. You have hyper pistons. We just went through this on another post. What are the piston to wall clearances set to? Even good places can screw up. It is imperative with hyper pistons in any application, that the piston to wall be correct per the manufacturer. KB hypers need it tighter than most. So if the builder went too big, the rings will not be as stable. Next is the wall finish and cleanliness. Leakdown won't indicate any oil ring conditions. So basically, tear it down. Verify the piston to wall, clean the hell out of the bores and walls, and install fresh rings. Any rings.
 
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