High Idle Issues 2001 XC 800

[Matthew LeVee]

At the end of last season my engine overheated due to a stuck thermostat. I replaced the thermostat and purged the system getting all the air bubbles out. I took my sled out for the first time this season yesterday. It starts right up and idles around 1500rpm which is fine. After riding for about 20 minutes, I came to a stop for a minute. At a dead stop with the engine running it idles at 4000 RPM and wont go down. Then the engine begins to over heat and I have to shut her down.

Since this issue, I took the machine out for a couple laps around my yard today to get the engine hot and same thing, 4000 RPM when I came to a stop. I put the choke on for a second to lower the rpms at which point the engine calmed down to about 1500RPM again and stayed there. All though sometimes it tries to creep up to 2000 RPM at which point I just choke it again and she comes back down.

I sprayed starting fluid around crank shaft, carb boots and engine head with no changes in RPMs ruling out any kind of leaks. What can my issue be? I have big trip in 2 weeks and this is starting to freak me out!

 

[Joe8585]

I had the same issue and was believed it to be the crank seal. Though uncertain, its definitely worth investigating more. You could try richening up the idle/air circuit and tweak the idle a little to keep er idling good. I would also add some oil to the gas just for some extra insurance, perhaps 100:1 with a good syn oil. Have you looked over at the flywheel side crank seal? its hard to diagnose that seal , but I wouldn't think it will hurt if you can get a spray or two behind the recoil area while shes running to see if theres any rpm change. Make sure your clutch rollers and arms are good and not binding up. good luck