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  1. #1

    STX 1100 Di top end rebuild questions-

    In the process of putting my ski back together. I bought it from a guy I know in non-running condition (#2 and #3 cylinders got very hot- wrecked the pistons and small end bearings took a lot of heat as well). #1 cylinder looks perfect, as do the crank bearings. I'm replacing the cylinder (chunk of liner was cracked in #3) and got a set of the Moly-coated WSM pistons to fill the new jugs with (and new bearings and gaskets)

    My question is this- what should I be looking for that would have caused those 2 cylinders to fail? The previous owner is an older guy and has owned it for the last 6 years- no issues. He reportedly took it out, it started running bad, brought it in and was told #2 had low compression. Oil tank is full, low hours (91). My thought is to check the oil lines from the pump to the throttle bodies- is there any sense in taking the throttle bodies off/apart? This was not a situation where 2 cylinders went full lean ( the plugs and piston crowns show normal)

    Any suggestions are well appreciated. Don't want to replace everything twice.


  2. #2
    Just finished a complete rebuild on an 1100 STX DI that the wrist pin came loose in, took out the cylinder liner, piston skirt broke off of it and punched a hole in lower crankcase. Not sure how you could overheat just the 2 back cylinders and not the 3rd. As I recall the water jacket is open between all the cylinders so if one has water they all should.

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