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Discussion Starter #1
heres a new one i think.  on one of my cylinders the lower exhaust valves actually crack off at the rods.  i thought it was a deffective valve so i switched sides and again it did it on that one cylinder in less than 10 miles of riding.  both clinders are like new and valves moved very freely so it wasn't that.  it seems like that one side the exhaust valve was sticking too low and the piston ring was catching causing it to crack off.  how can this be i mean everything is stock on it and its just the one cylinder.  i don't want to buy more valves just so it will happen again.  fortunetly i didn't wreck the piston or the cylinder.


thanks
 

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Sorry to say but this is not something new.  The 1998 and 1999 Sno-Pros used pressure actuated exhaust valves that were prone to breaking the way you describe.  The 1999's more than the 98's. There is an update for the valves available from A/C for the 99's.  E-mail me and I can look up the number for you if your dealer is clueless.
 I had a 1998 Sno-Pro. You must run good quality synthetic oil like Klotz or Amsoil. Keep those valves clean. But even then you can have problems. Even with the update there were breakages. By the 2000 M.Y. the Sno-Pros were using the servo valves you see today in production sleds.  If you are planning on trail ridding the sled, I would suggust updating the cylinders/pistons to the Hooper 640cc. These cylinders are direct bolt ons to your lower end, and eliminate the exhaust valves. Last I checked the kit sold for ~$2,500 and comes with a new pipe too.  This will really bring the sled alive. The chassis is great so this update is worth it. It makes for a great combo.
Rob H
mailto:[email protected]
 

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Discussion Starter #3
thanks for the info.  I still couldn't believe this happened though i took the vavles to the dealer and they had never seen anything like that happen.  they thought i put them in wrong but they were in correctly so who knows?  i thought this did have the updated vavles in it looking at the update kit at the dealer there wasn't much difference accept the little plate the valve rods went through.  I did buy the update kit and was it expensive!!!! i put it in last night and took it for a little ride though the neighborhood with no problems but that was maybe 3 miles if that.  i hope to god this doesn'y happen again.  i know these have to be cleaned all the time so i will be watching them closely

thanks

i wish i could get the 640 but a little out of my range right now
 
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