I would say they are fine, you might want to wipe the underside a little more, you'll find that will come off easily with a cloth. More for cosmetic and future diagnostic rather than function.
I'm assuming the ring grooves are clean
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine
Build thread starts here! Just doing top end rebuild as black rubber head seal allowed coolant to leak out! Got all parts and a little time so hoping to over the coming weeks! Three more pistons to go! Also, bought new barrels from brickwerks which came with MV pistons, only using the barrels! Question is they came with new gudgoen pins can I use these in DJ pistons or stick with original?
When I was a teenager a mate of mine used to build his own drag racing engines for his bikes - every surface was polished to a mirror finish, inlet, exhaust ports and pistons were all finished with jeweller's rouge after smoothing. But then the engine was only used once before being stripped and redone. He reckoned that it was worth it for that extra fraction of a second.
Ciaoflyer wrote:Ok, all cleaned! Any special tips for installing piston rings before I attempt it?
You will struggle to get the DJ top ring on without ring expander tool unless you have gloves and strong thumbs, they are strong and sharp, read the manual as to ring gap orientation and remember that the arrows point to flywheel and so 1&2 are the other way up to 3&4
compressions Rings have a top also
I lay barrels out as they go on with numbers and arrows on and so you don't make errors, then fit pistons straight into barrels.
Ciaoflyer wrote:Ok, all cleaned! Any special tips for installing piston rings before I attempt it?
You will struggle to get the DJ top ring on without ring expander tool unless you have gloves and strong thumbs, they are strong and sharp, read the manual as to ring gap orientation and remember that the arrows point to flywheel and so 1&2 are the other way up to 3&4
compressions Rings have a top also
I lay barrels out as they go on with numbers and arrows on and so you don't make errors, then fit pistons straight into barrels.