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I have a 2009 Sportsman 500 ho. It rums fine for maybe 15 minutes then dies as if there is no fuel. Sometimes adding fuel to carb will make it run for a second. After sitting for maybe 30 minites it will start again amd repeat the same cycle. I bypassed the quick connect to fuel sending unit incase it was sucking air. This did not fix it. I used. a syringe to test diaphragm in fuel pump. It clicks when activated with syringe. Does this have some kind of an overheat shut off safety switch? I am not getting any HOT warning lights Or codes.
 

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My first thought is it is drawing a vacuum on the fuel tank and fuel flow stops

Second thought is the fuel pump is faulty in some way, but with a full tank of fuel the problem would disappear until the fuel level fell to a certain point. If it was a fuel problem, immediately upon dying it would probably restart if the enrichener was used as though starting a cold engine. Fuel pumps don't just click - there is a spring and diaphragm inside the unit - when vacuum is applied it pulls the diaphragm against the spring, fuel is drawn through a check valve an fills the chamber and when the vacuum is released, the spring pushes the diaphragm putting pressure on the fuel - since the check valve on the fuel tank side is closed, the pressurized fuel is forced through a check valve into the pipe going to the carb - a check valve may have failed, the spring may have broken or the diaphragm may be damaged either not drawing fuel, not pushing fuel or leaking vacuum and simply not operating.

Third thought is the possibility that if it is a fuel problem, the vacuum line to the fuel pump might have a crack losing vacuum.

Fourth thought is that is is an electrical problem and it's losing spark when hot and returns when cooled down - coils will do that, but so can connections.

Good luck
 

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My first thought is it is drawing a vacuum on the fuel tank and fuel flow stops

Second thought is the fuel pump is faulty in some way, but with a full tank of fuel the problem would disappear until the fuel level fell to a certain point. If it was a fuel problem, immediately upon dying it would probably restart if the enrichener was used as though starting a cold engine. Fuel pumps don't just click - there is a spring and diaphragm inside the unit - when vacuum is applied it pulls the diaphragm against the spring, fuel is drawn through a check valve an fills the chamber and when the vacuum is released, the spring pushes the diaphragm putting pressure on the fuel - since the check valve on the fuel tank side is closed, the pressurized fuel is forced through a check valve into the pipe going to the carb - a check valve may have failed, the spring may have broken or the diaphragm may be damaged either not drawing fuel, not pushing fuel or leaking vacuum and simply not operating.

Third thought is the possibility that if it is a fuel problem, the vacuum line to the fuel pump might have a crack losing vacuum.

Fourth thought is that is is an electrical problem and it's losing spark when hot and returns when cooled down - coils will do that, but so can connections.

Good luck
I am having the same issues with mine! It runs great for 15-20 minutes no problem then it dies and it won’t start , I let it sit fit 15 minutes and it starts right back up and drives fine ! Any help would be appreciated
 

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2008 800 ho efi, 2019 850 SP premium
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I have a 2009 Sportsman 500 ho. It rums fine for maybe 15 minutes then dies as if there is no fuel. Sometimes adding fuel to carb will make it run for a second. After sitting for maybe 30 minites it will start again amd repeat the same cycle. I bypassed the quick connect to fuel sending unit incase it was sucking air. This did not fix it. I used. a syringe to test diaphragm in fuel pump. It clicks when activated with syringe. Does this have some kind of an overheat shut off safety switch? I am not getting any HOT warning lights Or codes.
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Premium Member
2008 800 ho efi, 2019 850 SP premium
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12,881 Posts
I am having the same issues with mine! It runs great for 15-20 minutes no problem then it dies and it won’t start , I let it sit fit 15 minutes and it starts right back up and drives fine ! Any help would be appreciated
Font Line Window Pattern Automotive exterior
to the forum
Ball Automotive lighting Vehicle registration plate Font Gas

From the Official Forum Greeter, be careful of the other imposters.
 
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