1997 Seadoo Challenger Engine Problems

[Shawnharris24]

Im having a problem with the performance of my 800 twin, I just recently put new pistons , rings and a upper gasket kit in and had the jet pump rebuilt dy seadoo,we were out with it and it got real hot because to my suprise the cylinders were full of sand,,, I had a end gap of 11 thous on the rings,,cylinders were bored by previous owner at .50mm(.020) i just freshened it up!! ive got good water circulation, only thing was the riser gasket i couldnt change the bolts they were frozen solid! It runs ok but at idle it acts like it seizes up, but when you let it sit for a little while it starts back up and runs for a while and then keeps doing this, it runs fine at wide open throttle, i however have never done anything with the carbs or oil injection pump,im just looking for some possibilities, the plugs look a little lean, not real dark and tan in the middle, they arent silver or anything like that!!Could a in line oil filter change and a turn up on the oiler help?? Any help would be greatly appreciated, I ran this boat for about 18hrs before i did the rebuild, this is a onset that has been gradually starting,,,Thanks Shawn