Topic: How are these pistons?

[stereosilence]

I got out some steel wool and some cleaning solution and went to town. They were COMPLETELY black before. I think they look better in person than in this picture. The dark spots seem to be staining. The 'grain' or brush strokes were already there. I know I need to carefully remove any buildup from the clip grooves and I have the new rings on there already. Anything else I need to inspect on these things?

[luap]

look clean. from other post make sure the holes around the perimeter are all open. test the ring gap before you put the in. Or maybe you already did it since the new rings are already on dont forget to give each ring a 1/4 twist at opening from each other. an if your ring compressor pops off before all rings are in the cylinder starts over. just my opinion

[dave500]

did you run a one millimeter drill bit through the oil holes where the oil control rings are?if not remove the rings and do it,,you will get crud,,just sort of spin the bit between your thumb and forefinger,use compressed air to blow out the crud aswell.

[stereosilence]

Ok. Thanks guys.

[lucky]

If the pistons were cleaned with a power wire brush they are probably ruined.
Those pistons look like they were put on a belt sander with 60 grit.

Better get a caliper out and measure from the top to the first ring land. In several spots.
If there is a big difference then they are ruined and out of balance.
If you have a grams scale weigh them. They should all be the same weight.

I hope you do not put those used piston rings back in the engine!!!
Did you number those pistons to the cylinders?

[stereosilence]

Rings are new. I did not use a sander or wire brush. I'm not sure what stock ones from a 550 would look like. I haven't gotten the impression that all this has been taken apart before, but I wouldn't know.

Originally, I set them out in order. I think I forgot and got them mixed up. So, no, I do not have them matched to cylinders (although I think the one with the big dark spot was #3).

Are there holes in the grooves? I didn't remember seeing any in there but earlier it was said that the rings should be removed and the holes cleaned.

[dave500]

those scratch marks on the crown are normal from the factory,dont worry they look ok,there are holes in the oil ring groove,get these cleaned through with a one mil drill bit.

[stereosilence]

Ok. Got the holes cleaned out. I used my crappy calipers to measure some, it seemed good. I measured the cylinders and they were spot on. I think if they were warped, there would be signs in the cylinder (and everything looked fine there).

[dave500]

did much crud come out of the holes?