I got the '94 Indy Trail out today to prep it for winter. I installed a xtra-10 skid this morning and ran it across the grass to test it out. Brought it inside to finish the prep and I check the compression every fall on the sleds to see how they are doing. Now I just pulled this back in the garage after 2-3 minutes running in the backyard and all was well. Compression on the PTO 125 psi same as last year Mag side 102. Well 12 years 3800 miles and the motor has never been touched, time to check it out. Pulled the head off and hhmmmm I thought I caught it before something major happened


When I pulled the head off the whole top ring was missing. Never had that before and it still ran fine bringing it into the garage this is what it looked like



I guess I'm just surprized at how well it ran then to see this. No miss, fired right up, the only odd thing was the compression check. Glad I didn't wait till the snow to check it out. Something others might want to think about before the snow flies.

If you are interested, I have 2 Wisecos complete, .010 over, 200 miles on them. $60 for both.

Thanks Dave but I just got back from the shop and I don't think .010 will clean it up. They are going to go .020 and see what it looks like.

Wow! I am surprised that you had problems with the 488 with that few of miles. I thought they were bulletproof. My 97 trail was always floored trying to keep up with my friends on the trail and never had an i ssue.

Thats the way this one was driven, pinned to the bar chasing the bigger sleds or towing the kids on a tobbaggon. Thing is it still ran and sounded fine it was the low compression that showed a problem. I have it back together now but for a fresh rebuild it seems I still have lower compression 118 lbs both cylinders. Anyone know the stock thickness of the head gasket? I got the Winderosa gasket set and never dealt with them before. Everything checks out (ring gap, piston to cylinder gap) will comp. rise during break-in? I can only think that the head gasket is too thick.

where did the ring go?

I am far from an engine builder but it does make sense that the break in period is to seat the rings and compression should rise.

I'm going to run it for awhile and see what happens. As for where the ring went.............. out the exhaust I guess because I couldn't find a piece of it anywhere.

488 F/C are far from bulletproof. I am up to .060 over with mine. Goes like hell, but got a hell of piston slap. I blew it up again last winter and it took a month just to find pistons for it. 300 dollars later it was finally back together. Learned a valuable lesson. Dont try to run out a problem, take things apart and figure out whats wrong.

urs is a lemon, i had a 92 indy trail 488 fan last year, thing had 10 000 miles and the motor has never been opened once, and i never had a motor problem other than my stupidity or running outta gas, and i ran it hard, fucken not a drop of snow on the ground, sunny day 22 c outside ripping up the hills in the sand pit, atempting to cross the ponds, up and down the road watching the sparks fly, thats fun at night. and nver a problem. other than carbides