finally getting around to installing pistons on my 360. Got number one installed, and when I grabbed number two to push ring down into cylinder to measure rings, I noticed the below gouge in the piston. Note it's not vertical, but the gouge was close enough to the ring groove, that I was not able to get the ring in, basically the gouge mushroomed into the ring groove . I've lightly sanded in the ring groove and now can get the ring in w/o any sticking. Wanted everyone Opinion on whether or not this will be a problem and have to get another piston or if it'll be fine and I just send it? Again it's not up and down, its across, so I don't think I will have any compression loss, but again, thought I'd share for opinions.. thanks!

 

I would be real tempted to replace that one......

 

Cheaper and easier now, just to find out it did the same to the cylinder wall, then your back to square 1, with an over bore machine shop charge, and 8 new Pistons and rings.

 

Yea, i hear ya. not sure if it came from summit this way or the machine shop did it when installing the connecting rods. my fault for not inspecting at the machine shop when I picked them up. also agree, mushroom doesn't look like it mushroomed towards the cylinder wall, only into the piston ring groove, and I agree, just spent $300 just to get it bored to .030.. so don't want to go any bigger worst case!.. back to summit for another piston. ugggg!

 

well called summit, can't get a single .30 over unless they can get w/ sealed power on Monday, which is still highly unlikely. did find single ones on Jegs for $40. did some measurements and believe this will be ok. I've installed the rings and will just go ahead and run this one. gouge is only about 2-3mm long, pics make it look worse, but there is no rise on the side of the gouge, was simply inside the ring groove which i've been able to fine sand down to fit the rings again. Piston don't ride the cylinder walls, the rings do, so I'm pretty sure it'll be fine.. thanks again for the replies..

 

Think I would still hit it with some emery cloth..... Likely I am just paranoid, but, I hate doing expensive jobs twice.

 

I did.. 😁😁😁💯

 

Buy once, cry once. Replace it, the ring groove is damaged. It WILL cause problems down the road if you use it.

 

Soloflite, are those pistons flat tops? Curious on when you have them installed are they below or above the block deck height?

 

Ok fella's, got a replacement piston, so not going to run the one w/ the ding. Got summit to replace. Engine coming together pretty good...Do have one question, I bought the Sealed Power Engine gasket set PN: 260-1864 for this rebuild, down to two seals that I'm not sure what they hell they are, one is the dizzy o-ring, which is to big(thickness), but the other that looks like a rubber washer, I'm clueless about what this is for. below you see these two pics of what I've crossed off the list and a side by side one of the dizzy o-ring and rubber washer. I will say, there is NO dipstick tube o-ring(one of the list that is not crossed out, so baffled as to what this rubber washer is. Please let me know if you do?





BT

Pistons top out at the top of the head, not sure what flat top pistons are, but these are sealed power .30 pistons.

BT

Here's some pics of the rebuild, hoping to get the rebuilt tranny w/ shifter kit mated up and both dropped in the truck in the next two weeks..