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drgrcr1156 05-18-2020 05:49 PM

Piston Skirt Recoating
 
Anyone have a bad experience with Line2Line piston coating. Having a few cylinders with hi blow by after a rebuild with their piston skirt coating. Not sure what to expect during break in with their coating. And as their coating breaks in, you are basically adding powder coating particles to the oil.

SSDiv6 05-19-2020 04:50 PM

Re: Piston Skirt Recoating
 
Quote:

Originally Posted by drgrcr1156 (Post 614886)
Anyone have a bad experience with Line2Line piston coating. Having a few cylinders with hi blow by after a rebuild with their piston skirt coating. Not sure what to expect during break in with their coating. And as their coating breaks in, you are basically adding powder coating particles to the oil.

It is not powder coating. The abrading coating imbeds in the piston skirt material and just wears out just like any other piston skirt coating. If you are having a blow-by issue, look at your rings and cylinder wall finish. Never had an issue with their coatings.

drgrcr1156 05-22-2020 07:41 PM

Re: Piston Skirt Recoating
 
I am not saying there is anything wrong with the coating. I think it is a great process to overcome cylinder wear without having to bore the block. I am just trying to learn what to expect during break in. I do not want to pull it apart if it is not necessary. The engine has barely been run for 20 minutes over 3 days. Maybe the rings have not seated in 3 cylinders but will with more time it will. My biggest concern is the blue smoke coming from the vacuum pump breather. The other concern is running the engine up to full tilt while on jack stands as part of the coating break in procedure.

Mike Graham 05-22-2020 07:49 PM

Re: Piston Skirt Recoating
 
I did 3 engines last year with their coating. Two were fine. One had exactly that problem.
The coating stuck to the rings. The leakage would move every time we heat soaked the motor. I know it was the coating because it was a re ring. It didn't have the problem before the coating and didn't have the problem after the pistons were replaced.
Just my experience.

MAURICE BLENDHEIM 05-22-2020 10:20 PM

Re: Piston Skirt Recoating
 
See questions in my next post.

MAURICE BLENDHEIM 05-22-2020 10:25 PM

Re: Piston Skirt Recoating
 
Guys... Just wondering what your final cylinder cleaning procedure was before assembly? What ring package and brand did you use? What bore finish? MB

Mike Graham 05-22-2020 11:55 PM

Re: Piston Skirt Recoating
 
The particular engine that I had trouble with Had Total seal AP rings the first time and Ackerly and childs moly the second time. I have used both brands of rings many times with no issues. Hone on this guy was 820 . The only thing we changed was to have the pistons coated. The engine ran fine but was ready for re ring. Same hone same ring pack. The only thing changed was coated pistons. Engine ran good for about 10 passes then fell off a tenth. Everytime we would leak it leakage would change. Second rings were trashed. Re honed and re ringed.Same results. I have done more than a few stock and ss engines and never had a problem like this before or after. Like I said, the only thing that was changed was coating. I think the coating on this particular set of pistons was too soft and it sloughed off. I did 2 other builds with this coating without problems. I didn't see any gains,but it didn't trash the rings.

Glenn Briglio 05-23-2020 06:18 AM

Re: Piston Skirt Recoating
 
The coating thickness for some reason can be a problem. I've used Calico to coat piston skirts.They have three different thicknesses of coatings.If I use the extra thick coating I've had problems sometimes with it coming off.

drgrcr1156 05-23-2020 01:00 PM

Re: Piston Skirt Recoating
 
This rebuild included Total Seal Gapless rings with ultra-low tension oil rings. The fact that when I start it, there is immediate blue smoke coming from the vacuum pump breather tank, leads me to believe the rings have gummed up just as I have read here.

Jim Hanig 05-23-2020 05:58 PM

Re: Piston Skirt Recoating
 
Quote:

Originally Posted by Mike Graham (Post 615198)
The particular engine that I had trouble with Had Total seal AP rings the first time and Ackerly and childs moly the second time. I have used both brands of rings many times with no issues. Hone on this guy was 820 . The only thing we changed was to have the pistons coated. The engine ran fine but was ready for re ring. Same hone same ring pack. The only thing changed was coated pistons. Engine ran good for about 10 passes then fell off a tenth. Everytime we would leak it leakage would change. Second rings were trashed. Re honed and re ringed.Same results. I have done more than a few stock and ss engines and never had a problem like this before or after. Like I said, the only thing that was changed was coating. I think the coating on this particular set of pistons was too soft and it sloughed off. I did 2 other builds with this coating without problems. I didn't see any gains,but it didn't trash the rings.

Mike i would call Carl at poly dyn used his coating for years never had a problem. 2818946382


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