[WayneGSpooner]

My 2003 Yamaha 800XLT is having problems. I have exhausted all of the things I can do (plugs, fuel, oil, basic electrical etc) but it still shuts off at high rpm and often struggles to start again. Seems more electrical in nature other than carb issues. The shut off just seems too abrupt.

Can anyone recommend a reputable repair shop in my area? I live in Merritt Island, Florida.

Would appreciate a recommendation.

Wayne

 

[robby287]

I am having this very same issue with my ski, It is a 2002 XLT 800 has only 51 hours on it, any ideas what it might be?

 

[WayneGSpooner]

Oil starvation, rear cylinder. The oil lines from the oil pump to the carbs are not securely attached (tie wrap) and cannot be easily inspected. The rear cylinder lost oil, bye bye engine. Would start and run (presumabbly due to some lubrication from the front cylinder) but at high RPM it would dry seize. Cool off & it would run again. Eventally burned a hole in the piston & I became great friends with SBT in Tampa.

Runs better than ever. No oil pump, runs on 35:1 premix

 

[costellokg]

I have two 2001 XL800, both motors have blown pistons, but don't recall if they were both the rear cylinders. If the rear oil line came off, wouldn't there be a lot of oil in the engine compartment? My main problem has been with power valves - one broke off at the shaft and fell into the cylinder, destroying that piston. Another was completely gone and the last failure was the retaining pin came out and the piston started eating the edge of the power valve. Have R&D billet power valves on order now.