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96 Polaris Indy 500 runs then dies

D
Jan 11, 2017
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I have a 96 Polaris Indy 500, it starts up cold and runs perfect, good throttle response, but after 10 min of riding it, it Bogs down and dies, then never restarts. I've replaced all fuel lines,needles and seats, keys, intake boots, new coils. It's got good spark and seems to be getting fuel (at least when its runnin) any ideas?
 

sled_guy

Well-known member
Premium Member
Jul 5, 2001
3,566
843
113
Riverton, Utah
When it dies, have you checked to see if it has spark at that point?

Make sure your tank is venting correctly, if the tank vent is blocked then it will slowly pull a vacuum in the tank and stop the fuel flow. You can check that by just cracking the cap open when it dies and see if it sucks air in.

If you let it sit and cool off then it will restart? Might be the CDI... I had one of those older twins that would idle fine when hot, but not rev up. Turned out it was the CDI when it got hot wouldn't advance the timing at all.

Did you also replace the pulse line from the motor to the fuel pump? It could be getting warm and then collapsing causing the fuel pump to not work. Probably easiest way to check the fuel is when it dies, pull one of the fuel lines off the carbs and try and start it, watching for fuel to squirt out of the fuel line. If it does then you know the pump and lines are working fine.

And last but not least, check the fuel feed line in the tank. Older machines with the ethanol fuel we have these days tend to have that pickup line rot. It can either fall off or get holes in it causing it to suck air and start the motor for fuel.

sled_guy
 
A
Jun 23, 2004
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Black Diamond, WA
Gotta see if It has spark after it dies too. the cdi or the stator can short out once it gets heat soaked and the wires expand.

And redo the ends on the spark plug wires. Sounds weird but I had a sled I thought stator was going bad and turned out the plug wires were just shorting out at the terminals where they screwed in. Just wore out the connections
 
D
Jan 11, 2017
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OK, I replaced fuel line in tank, and fuel filter, and pet ****, has new Cdi, gas tank seems to vent as I can hear it when I sit down on the seat. Has new plugs and I double checked plug ends and they seam to be in straight, got s good spark after it dies, but don't seam to have fuel, I'll check fuel line coming from engine this evening.
 
T

trestlecreek

Well-known member
Sep 19, 2010
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Like they said, see if both plugs have spark. Its OK to cross the plug wires and trace to see if its a Coil. They both fire at the same time on two strokes. Some times when a coil is going out, it will shut down when Hot but work when cool...
 
D
Jan 11, 2017
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Ok, got it out yesterday after checking everything mentioned. It ran strong for 30 min and I was thinking it was finally good. But it bogged dwn and died,this time I had more tools and was able to Ck a few things it appears to stop getting fuel, fuel goes through filter and shut off and is getting to the pump but not from the pump to carbs, I pulled the line off coming from crank case and tried to pull air through that line on the fuel pump and couldn't pull air so I'm thinking the diaphragm is ok. Any thoughts?
 
J
Mar 24, 2015
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My 1996 500 EFI is doing the exact same thing. Runs for about 20 minutes and then completely dies. At the point when it dies, the fuel pump is not getting a signal to pressurize the system. The 500 EFI’s have a system that sends a signal to the fuel pump to pressurize the system if you pull the motor over even so much as a revolution. Even with the kill switch off and the ignition off. Even unhooking and re-connecting the battery will cause the pump to pressurize for 3-4 seconds. When mine is dead, the pump is not receiving the signal anymore. No matter what I do.
 

BeartoothBaron

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Lifetime Membership
Nov 2, 2017
1,233
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Roberts, MT
Yeah, the EFI system isn't tied in with the kill circuit, so if yours is dying and the pump doesn't cycle when you pull the rope, then you've got an EFI problem and not ignition. I'm pretty sure the original poster's sled was carbureted though (he never mentioned EFI), and it's a couple years old too. Might make more sense to start a new thread...
 
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