I got a set of sweet looking 4.03 4.00 pistons inboard forged from JE. They were shipped to Polydyn in Houston to get coated before I got them. My block and rotating assembly was already at the machine shop so I dropped the pistons off with them as soon as I got them.

I'm sitting here tonight building this shortblock and I grab the piston for the #6 hole. After it's assembled I try to slide it in the bore and it doesn't fit. I grabbed my T-Gauge set and mic'd the hole out thinking it was a machining problem. The holes were all within several ten-thousands of each other. I slide the piston in crown first and it fits fine. So I mic out the skirt and it's 4.054!

The first thing I thought is... they went way to heavy on the coating. The coating is exactly like the other pistons. I took an emery board and knocked some of it off and it's microns thin...

So basically what I've got here is an expensive COATED piston that isn't worth hitting a hog in the *** with. Polydyn missed this somehow... The machine shop missed it.


I just needed to rant. I was really looking forward to building this block tonight. Has anybody had any similar problems with a piston? How's JE's customer service? They were closed before I found the problem. Being that the piston is coated I wonder if they're going to give me any ****.

Also, What's your opinion on running one piston uncoated? The crown is ceramic coated and the sleeves have their oil slinger formula. This would probably make a difference in the cylinder temperature.

Thanks,
Andy

 

 

i'm running JE pistons in my 383 stroked motor. There customer service is A+

I have no doubt they will take a look at that pistons (even coated) and replace if fault is on their side.

 

Let us know what they say.

 

JE is going to fix it or replace it. Polydyn is going to re-coat it for free.

Both companies are A+ in customer service.