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2002 500 Sportsman won't rev

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Old 08-07-2013, 06:58 AM
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Default 2002 500 Sportsman won't rev

My friend has an 02 sportsman 500 RSE that quit running, and left it sitting outside for 6 months. After some trouble shooting we found the trigger coil to be bad. Replaced it and tried to start it, It has a good spark, but it wouldn't start. He decided to put a carb kit in it and after that it will start, but you have to hold the throttle wide open to get it to run at a fast idle. Also it seems to have no response to the throttle. Any ideas?
 
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Old 08-07-2013, 09:29 AM
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Valve adjustment checked? Fresh fuel also? Good fuel flow from the fuel pump to the carb? Carb slide lifts and falls ok?Was the slide needle removed,clip and spring replaced properly? Carb all the way in the intake boot? Some would pull out because of the mounting brackets.Clean air filter? I think I'd retrace his steps on the carb first. If it was sitting out side unprotected for 6 months,could have trapped moisture in the electrical component connections causing problems? I'd even pull the recoil housing and clean the face of the pulse coil and around the flywheel in case of dirt/rust. Just eliminate one area at at a time.
 
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Old 08-07-2013, 05:02 PM
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I would check the carb first.
 
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Old 08-15-2013, 08:54 PM
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Originally Posted by old polaris tech
Valve adjustment checked? Fresh fuel also? Good fuel flow from the fuel pump to the carb? Carb slide lifts and falls ok?Was the slide needle removed,clip and spring replaced properly? Carb all the way in the intake boot? Some would pull out because of the mounting brackets.Clean air filter? I think I'd retrace his steps on the carb first. If it was sitting out side unprotected for 6 months,could have trapped moisture in the electrical component connections causing problems? I'd even pull the recoil housing and clean the face of the pulse coil and around the flywheel in case of dirt/rust. Just eliminate one area at at a time.
I put new fuel in it, it has good flow from the fuel pump, carb slide is good, when we took the carb apart, the clip wasn't attached to the to the needle. I have tried it in several positions, but not sure which slot to put the clip in for sure. Any idea?

I had it on the center position and it seemed to be flooding, so I have moved it to the top position. When I try to start it I choke it, then when it hits it will run for about 2-3 seconds and die. I'm kinda leaning toward valves but haven't got to that yet. It has backfired a couple of times while trying to start it. How can I verify the timing is correct?
 
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Old 08-16-2013, 12:20 AM
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Place the needle clip in the 3rd position from the top.Install a new carb kit. Just "cleaning" a carb doesn't always work right especially if the needle and seat are worn allowing too much fuel.. Timing and advancement is controlled electrically through the cdi module.http://www.ebay.com/itm/CARBURETOR-CARB-REBUILD-KIT-POLARIS-SPORTSMAN-500-2002-/290943094412?pt=Motors_ATV_Parts_Accessories&hash=item43bd8f4e8c&vxp=mtrPlus float level setting is critical on this carb. Yours has the same basic Mikuni carb as illustrated with a few differences,but it's on a KTM. Float level adjustment is towards the end.http://www.advrider.com/forums/showthread.php?t=347184
 
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Old 08-18-2013, 09:24 AM
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About engine timing...When I have the flywheel timing mark aligned in the site hole, should the cam gear be in the position with the 2 dots parallel with the rocker housing?
 
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Old 08-18-2013, 10:06 AM
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If you haven't messed with the cam chain,when you view the cam sprocket, the cam index pin should be center of the head,the two marks slightly to the left and right.
 
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Old 08-18-2013, 10:20 AM
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they are slightly to the left. not centered. I noticed this when I checked the valves. What do you recommend?
 
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Old 08-18-2013, 10:51 AM
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As long as the index pin is dead center of the head,the cam chain is tight,and shows to be on the TDC mark on the case pointer,don't worry about the exact placement of the two dots.If the cam chain has excessive slack,then it might be time for replacement.
 
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Old 08-18-2013, 11:37 AM
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It looked to me like they were about 11 o'clock if 12 o'clock was the center of the head.
 


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