A
2009 Ski-Doo 50th Anniversary Edition (41 of 500) 800R Power T.E.K. 154"
Hello all,
I rode with a friend last year, and after dropping down from 4000' feet to 3000' his engine seized up, I pulled the belt, noticed the coolant bottle was empty, filled it with water, and tried to roll the primary. It felt solid so we did not even pull the spark plugs, just loosened the track and towed it downhill. After sitting all summer, we tore it down slowly and found:
First, he had complained of the sled of backfiring before, and installed new pre-gapped plugs before this ride.
1)The PTO Spark Plugs' ceramic had split at the tip, and the pieces bounced around and did a number on the piston. The piston and head looked clean of carbon. There was a crack on the exhaust side, crescent shaped, going down past the ring by about 1/32nd.
2) The MAG Spark Plug had coolant in it as did the cylinder itself. The dome, and piston had combusted material on it, I am assuming it is leaked glycol....
The combusted material looked as if it had been disturbed in four spots, perhaps "washed."
3)The exhaust pipe was full of coolant.
After pulling the heads, I rolled the clutch and notice that the PTO cylinder seems to have a lot of play at Bottom Dead Center, as In I can roll the crank a few degrees in either direction, and the piston stays still.
The MAG piston has a lot of play forward to back in the cylinder.
So obviously there are some parts to replace here, pistons, rings, wrist pins,
but I am having a hard time deciphering what happened here.
The simple answer is that the head gasket failed and dumped coolant into the MAG side cylinder and locked the engine up, we filled the coolant bottle and as the coolant level equalized it filled the whole engine cavity.
If so, what caused the head gasket to fail, did he overheat and the head lifted slightly?
Had it been leaking for awhile causing the sled to backfire and build carbon up on the MAG side? (The combusted material I assumed to be coolant, could be accumulated carbon.)
Is the play I feel on the PTO piston at BDC something to be concerned about?
Am I just making something out of nothing with that few degrees of rotation?
I am unfamiliar with the 800R Power TEK, is there something common with these motors I am overlooking? Is there something else I should be looking for? I believe the are case cooled, meaning the lower case is water jacketed.
Am I looking in the wrong area, could this be a water jacket crack vs. a failed inner head gasket o-ring?
Is there a drain plug to drain the combustion case of coolant or water in case of a water submersion.?
I can add photos if it would help.
Thank-you for any help gents.
Hello all,
I rode with a friend last year, and after dropping down from 4000' feet to 3000' his engine seized up, I pulled the belt, noticed the coolant bottle was empty, filled it with water, and tried to roll the primary. It felt solid so we did not even pull the spark plugs, just loosened the track and towed it downhill. After sitting all summer, we tore it down slowly and found:
First, he had complained of the sled of backfiring before, and installed new pre-gapped plugs before this ride.
1)The PTO Spark Plugs' ceramic had split at the tip, and the pieces bounced around and did a number on the piston. The piston and head looked clean of carbon. There was a crack on the exhaust side, crescent shaped, going down past the ring by about 1/32nd.
2) The MAG Spark Plug had coolant in it as did the cylinder itself. The dome, and piston had combusted material on it, I am assuming it is leaked glycol....
The combusted material looked as if it had been disturbed in four spots, perhaps "washed."
3)The exhaust pipe was full of coolant.
After pulling the heads, I rolled the clutch and notice that the PTO cylinder seems to have a lot of play at Bottom Dead Center, as In I can roll the crank a few degrees in either direction, and the piston stays still.
The MAG piston has a lot of play forward to back in the cylinder.
So obviously there are some parts to replace here, pistons, rings, wrist pins,
but I am having a hard time deciphering what happened here.
The simple answer is that the head gasket failed and dumped coolant into the MAG side cylinder and locked the engine up, we filled the coolant bottle and as the coolant level equalized it filled the whole engine cavity.
If so, what caused the head gasket to fail, did he overheat and the head lifted slightly?
Had it been leaking for awhile causing the sled to backfire and build carbon up on the MAG side? (The combusted material I assumed to be coolant, could be accumulated carbon.)
Is the play I feel on the PTO piston at BDC something to be concerned about?
Am I just making something out of nothing with that few degrees of rotation?
I am unfamiliar with the 800R Power TEK, is there something common with these motors I am overlooking? Is there something else I should be looking for? I believe the are case cooled, meaning the lower case is water jacketed.
Am I looking in the wrong area, could this be a water jacket crack vs. a failed inner head gasket o-ring?
Is there a drain plug to drain the combustion case of coolant or water in case of a water submersion.?
I can add photos if it would help.
Thank-you for any help gents.
