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Discussion Starter #1
Anyone ever seen one jump timing? Im just looking for ideas here but I bought a sportsman 700 today that I was told belonged to the guys uncle who died. Learned shortly after that the guy lied about that and he had just bought it a few days ago. He said it needed carb cleaned and a battery because it sat for quite some time. Only had 700 miles on it so I bought it. After I bought it I realized that I recognized it because I called the original seller earlier this week. Sure as heck I still had the guys number in my phone so I texted him and he explained to me that he thought it jumped time or maybe dropped a valve. I tore into it and put the compression tester on it and it pulled 60lbs on one and about 30 on the other. I pulled the valve cover off and observed the valve train and it looked good. I pulled the exhaust rockers off and ran the compression again and pulled 150lbs on each cylinder and both maintained that compression and did not leak down. Put rockers back on and pulled 100 lbs on one and 60 on the other. Shot it with ether and it would not run. Confirmed that it does have spark.

Looking for ideas here guys. Any thoughts?

If anyone needs parts I may be parting it out to try to recoup my money.
 

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Timing is gear driven on the right side under cover, these are a push rod motor, the cam is under the cylinders like a harley motor, valves are non adjustable could have jumped a tooth on timing gears so that valves are opening when they should be shut, tghere should be a manual for it at tha top of this section , in the stickies.
 

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Discussion Starter #3
Thanks Russ. Update: One of the cam retainer screws backed out (other two were hand loose) and got in the gears and broke camshaft. Only reason the cam turned is because it was not clean break and the jagged edge forced the cam to turn. Two bent pushrods on intake side but valves and pistons survived.
 

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Glad you got to the bottom of your issue. I have decided it is best to buy a non runner for parts only. :( I priced a cam for our 325 last week and it was around $400 from Polaris.
 
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