Ideas on wtf went wrong here?

bl817

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did you check your piston rings for end gap? wondering if they are what scored the cylinder wall.
 

05sonic4.6

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I had installed top and middle rings at .024 per modmax recommendation. I was running there file fit rings.
 
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bl817

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did you actually install them by themselves in the corresponding cylinder and check end gap? there is a squaring tool that seats the rings flush or square in the cylinder so you can check end gap. you could use the piston upside down in a pinch. each ring needs checked individually and filed to correct gap. too much gap will allow a small amount of blow by and not to terrible, not enough and gap closes fast and ends forced out, scratching cylinder wall.
 

05sonic4.6

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Yes every ring I paired to each cylinder and was checked squared and filed accordingly. I was very thorough and meticulous, at least I think I was ha. Aside from my moment of retardation with lubing the pistons and cylinders.
 

LikeabossTM

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Yes every ring I paired to each cylinder and was checked squared and filed accordingly. I was very thorough and meticulous, at least I think I was ha. Aside from my moment of retardation with lubing the pistons and cylinders.

That unfortunately is sometimes the worst part - that you don't know what you don't know.
 

05sonic4.6

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It was warmed up to normal operating temp. It was the second time I took the car for a spin before the valve started bending.
 

rickf

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There is a whole lot of armchair quarterbacking going on here from people that cannot see the engine in person and that had no hand in the assembly. The reason I say this is because there are more reasons given for the demise of this engine than I have ever seen but I have yet to see any solid exact to the thousandth measurements. I am not trying to be a smart ass but nobody is going to be able to diagnose the problem online, myself included. We can surmise but that is just a fancy word for "Guess". Have you had any correspondence with the machinist and what has he said? You need to take everything to him and have him look it over and he can tell you exactly what happened. If he is an honest guy he will own up to a mistake he made. I have seen it happen many times. Not all machinists are crooked.
 

05sonic4.6

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There is a whole lot of armchair quarterbacking going on here from people that cannot see the engine in person and that had no hand in the assembly. The reason I say this is because there are more reasons given for the demise of this engine than I have ever seen but I have yet to see any solid exact to the thousandth measurements. I am not trying to be a smart ass but nobody is going to be able to diagnose the problem online, myself included. We can surmise but that is just a fancy word for "Guess". Have you had any correspondence with the machinist and what has he said? You need to take everything to him and have him look it over and he can tell you exactly what happened. If he is an honest guy he will own up to a mistake he made. I have seen it happen many times. Not all machinists are crooked.

We've already basically established that the cylinder damage was by my own hand. The heads on the other hand were most likely assembly error by the machine shop. And when I did confront him about the damage to the heads he said pumping the lash adjuster prior to install was what cause themm to bend which is bs. This is all stated in the previous posts.

I'm at the point we're in going to be taking what I have left of my bottom end and block to another shop to see if it's salvageable. I'm hoping I can just get away with a fresh hone and new rings but we'll see.
 

rickf

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I agree that the lash adjusters were not the issue. #1, pumping them up is not going to do squat as far as them holding the valves open. They have oil pressure in them to do that and #2, there was no significant PTV contact that would have occurred if that were the case. Ok, maybe there are a few dishonest machinists out there.
The point of my last post was this, everyone is posting a new diagnosis trying to be the guy who got it right and at this point it is moot. I think the direction you are headed is the right one, get references on the new shop ahead of time! Good luck.
 

deebo05

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i have been lurking on this this thread, i really have a few questions.

whats the set up on the build?

got pics of the rod bearings?

thats 20 miles on those heads? those chambers are dirty.

what did you torque the head studs too?

was that the correct piston to bore clearance?

did you miss the tune up?
 

05sonic4.6

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i have been lurking on this this thread, i really have a few questions.

whats the set up on the build?

got pics of the rod bearings?

thats 20 miles on those heads? those chambers are dirty.

what did you torque the head studs too?

was that the correct piston to bore clearance?

did you miss the tune up?

Stock crank boss rods diamond 15cc Pistons

Rod bearing we're looking good they still hadnt worn that break in coating off yet that kings puts on them i forget what it's called. That's how little I drove it.

Tune was prob on the rich side. I was datalogging it for further tuning when shit went down. Lito is doing the tune so I really doubt the tune was any issue.

Piston to bore clearance is closer to .004 which is within spec maybe a touch on the tight side. But my gage isn't the best.
 
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