I tore down the top end tonight on the 488. The carbs looked overall nice, with not much gumming and no noticeable clogs. I carb cleaned 'em nice and clean now.
I attached a few pics for feedback. It was blowing way too much smoke on startup. It'd fill up the 3 1/2 car garage in about a minute. I only had time to run it a few times in the back yard this March before the season ended. Could it be the rings or the jet settings off?
One of the pics shows the rings with the gaps together to show how much gap there still is. I pushed the opposite ends of the rings all the way into the grooves. Best I could figure the gaps were both at 11/32". What is a tolerable gap, before needing new rings? Will new rings give me any exhaust relief? Is it more likely the carbs weren't properly jetted/clogged?
The pistons look to be original, and just with carb cleaner and a rag I was able to take off all the carbon built up on top of the piston and the head. For the 9K miles it looked really clean to me before cleaning. I also felt the piston skirt and the cylinder wall and felt no grooves of any kind. Any telltale trouble spots I should check, like too much play with the piston and its pin?
I did notice that the ring gaps were very close to each other, towards the intake side, when I would have thought they should be 90 degrees left and right of the intake.
The lower cover pic shows left exhaust side oil. I pulled off the spark plug wires from the plugs and oddly/sadly the left spark plug tip had part of the wire end on it. I'll need to buy a new set. Stuff keeps adding up, although doing all the work myself should be some consolation.
While I have the heads off, should I throw any bottom end crank oil in there?
As for jetting, the idle jets s/b turned in all the way gently, then let out three full turns? Acceleration jet or whatever it's called s/b opened 3/4 turn? Idle on startup s/b around 1,500?
Any gasket brands to consider (or don't touch)? Same for piston rings?
93 Polaris Indy Trail Deluxe 488 recondition