Scrambler 500 Stalling when hot
#1
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I am hoping someone out their can help me out. I have recently purchased a '99 500 Scrambler HO....rode all winter without a problem. Now that the heat has arrived, it is stalling when the quad gets hot. Seems like it is starving for fuel after riding for 10-15 minutes....today I pulled the tank, fuel filters, vent lines, air filter, carb etc and cleaned and checked everything I thought might be causing the problem. It worked better, but it still stalled on me. I blew air into the tank vent line and it seems to help, but it will not run consistent.....could it be fuel pump, coil???
Met a couple guys on the trail that suggested I post to this site. Anyone who has had any experieince with this or thoughts on how to fix.....looking for help.
Met a couple guys on the trail that suggested I post to this site. Anyone who has had any experieince with this or thoughts on how to fix.....looking for help.
#2
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#8
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Your problem is probably not fuel related. Believe me, I replaced a whole ton of Sh*t on my bike before I actaully found the problem. With 95% confidence I would say that your problem is a worn exhaust lobe on your camshaft. The 500cc Polaris engines are famous for it.
I replaced mine with a used one (along with a used Exhaust Rocker) that I bought off ebay for $120.00. It took me three hours to fix it myself (And I am not very mechanically inclined) with the aid of a shop manual.
I should be good for another 7 years!!
I replaced mine with a used one (along with a used Exhaust Rocker) that I bought off ebay for $120.00. It took me three hours to fix it myself (And I am not very mechanically inclined) with the aid of a shop manual.
I should be good for another 7 years!!
#9
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Originally posted by: mnorton
Your problem is probably not fuel related. Believe me, I replaced a whole ton of Sh*t on my bike before I actaully found the problem. With 95% confidence I would say that your problem is a worn exhaust lobe on your camshaft. The 500cc Polaris engines are famous for it.
I replaced mine with a used one (along with a used Exhaust Rocker) that I bought off ebay for $120.00. It took me three hours to fix it myself (And I am not very mechanically inclined) with the aid of a shop manual.
I should be good for another 7 years!!
Your problem is probably not fuel related. Believe me, I replaced a whole ton of Sh*t on my bike before I actaully found the problem. With 95% confidence I would say that your problem is a worn exhaust lobe on your camshaft. The 500cc Polaris engines are famous for it.
I replaced mine with a used one (along with a used Exhaust Rocker) that I bought off ebay for $120.00. It took me three hours to fix it myself (And I am not very mechanically inclined) with the aid of a shop manual.
I should be good for another 7 years!!
Younger, that could be your problem due to the heat causing the exhaust valve to not open all the way when your engine gets warm
#10
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Finally got a chance to get back to you....thanks for your help, but after several tear downs and inspection of hoses, fuel pumps, carb etc, I pulled the fuel valve out of the gas tank......you wouldn't believe the amount of dirt on the intake filters for both the main and reserve lines.
I cleaned them up and it no longer stalls........now if I can just get it to stop backfiring when I let off the throttle.
I cleaned them up and it no longer stalls........now if I can just get it to stop backfiring when I let off the throttle.