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12K views 39 replies 13 participants last post by  crazyflyboy30  
#1 ·
Im on my third Quantum for my 2017 Sportsman 850. Same problem every time. Once it gets to temp and runs fine for about 20min then after that the fuel pressure drops to 17-20psi. It wont rev up and backfires. It will idol rough though. Anyone have a suggestion?
 
#2 ·
Welcome to the forum
 
#5 ·
I called Quantum today. Spoke with Scott in the Technical questions department. He suggested a few things. First he said to look for a leak in the fuel system. I explained that if i had a leak then i would have fuel all over the place. I also asked him if he meant at one of the injectors. The fuel rail holds the 20psi after i shut down indefinitely. This kinda rules that out. He then suggested I get my ECU flashed. He said without a doubt the fuel pump is not the issue when i told him it was louder than usual while maintaining that 20psi. What do you guys think?
800mi 200hrs on the quad. I purchased the whole unit direct replacement. It includes fuel filter and pressure regulator. I ordered another pressure regulator to test later this week. I guess my question would be does the ECU vary the amps to the fuel pump as demand increases or decreases. I would think it would be consistent. Polaris dealer in denton could not answer my question. What do you all think?
 
#6 ·
I called Quantum today. Spoke with Scott in the Technical questions department. He suggested a few things. First he said to look for a leak in the fuel system. I explained that if i had a leak then i would have fuel all over the place. I also asked him if he meant at one of the injectors. The fuel rail holds the 20psi after i shut down indefinitely. This kinda rules that out. He then suggested I get my ECU flashed. He said without a doubt the fuel pump is not the issue when i told him it was louder than usual while maintaining that 20psi. What do you guys think?
800mi 200hrs on the quad. I purchased the whole unit direct replacement. It includes fuel filter and pressure regulator. I ordered another pressure regulator to test later this week. I guess my question would be does the ECU vary the amps to the fuel pump as demand increases or decreases. I would think it would be consistent. Polaris dealer in denton could not answer my question. What do you all think?
The fuel pump is powered by a fuse with relay so needs full power all the time it's running and the over flow is let off by the pressure regular in the tank.
If you know for sure that it's making enough pressure it must not getting enough power.
 
#12 ·
Im going to remove the plastics tomorrow (im very good at it now) and test everything electric under load related to the fuel pump. Now when i turn the key it primes but only 17 psi. I really think i got another bad pump. I also purchased a new quantum pressure regulator i’ll try it as well. I’ll post the solution once I find it and if you guys think of anything please let me know.
 
#17 ·
Quantum This is what I’ve been purchasing. I tested voltage and amps under load at the pump on the bike (i tapped into the power wires below the lid). 12.4v ~6amp under start load. Got 17psi at the top of the sending unit. Removed the unit. Bench tested in a bucket of fuel. Got 17psi and ~6amp. Replaced pressure regulator. Same results. Clicked return on amazon and ordered a feidks 47-1002 off amazon for $55 shipped. I will try this one. Identical to the Quantium. Same part number as the All Balls. I think they are importing these and rebranding. Pretty common for a bunch of stuff these days. Anyway, i’ll let you know. I’ll just buy OEM if this does not work. Gotta love amazon’s return policy.
 
#24 · (Edited)
Hello, I want to share my findings on fuel pump issues on my 2017 Sportsman 570. I purchased it 6 months ago and it has 4500 miles.
1st ride ran great but I noticed it hesitating a couple times toward the end of a 4 hour ride. I chalked it up to some water I had been running thru.
2nd ride, started out fine then stumbling about 30 min into the ride. It got progressively worse until I was barely able to limp back to camp.
Home, I read the discussion board, tested all electrical sensors and inspected as much wiring as I could. Didn't find anything of significance so I decided it was probably the fuel pump.
Ordered a new pump assembly from Quantum.
3rd ride, ran great for 4 hours then quit and would not restart. Towed back to camp.
Home, ordered a fuel pump pressure test kit. Tested pump and showed 8 psi. Removed the pump and discovered the pressure line was off (see pic)
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Installed hose clamps and pressure test shows 58psi. Since my fuel line came off completely it was easier to diagnose than leakage around the hose fittings under pressure. Since it was a hot day and a long ride the fuel line became very pliable. I wonder if partial leakage around the fuel fittings after the tank is warm is a very difficult to diagnose issue for many?

This got me curious about the old fuel pump I had replaced. This was a factory pump with the Quantum kit in it. I tested it and the pressure was low 20psi to low 40 psi. While testing I observed leakage around the pressure hose fittings even though they had clamps. On inspection of the pressure hose I discovered it was deteriorated, rock hard and would spin in place even though clamped. Further inspection revealed it was NOT submersable fuel hose. Additionally while comparing the new pump assembly with the old pump/kit I discovered the orientation of the fuel strainer on the old pump (on the right) is 180 degrees off from the new pump (on the left see pic) and what is shown in the Polaris service manual.
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The incorrect strainer on on the old pump appears to be the same as the replacement shown on the Quantum website. I will call Quantum Monday to see if a replacement with the correct orientation is available as I cannot find it on the website. If anyone knows the part number or where I can procure please let me know! I think it is important as when inserted into the tank with the wrong strainer the strainer folds up and could be contributing to fuel starvation, especially when below 1/2 tank of fuel. I re-tested the old pump with a temporary replacement fuel line and no strainer, 58psi.

My takeaways:
Only use submersible fuel line.
Always install Injector hose clamps on both ends of the pump pressure line.
Make sure the fuel strainer has the correct orientation.
 
#25 ·
Looks like I got it. Amazon knock off pump (Exactly the same as the Quantum) primed and is holding 57Psi. Im going to idle it for an hour. All the Quantum pumps (3) prior to this failed. Bought them on amazon. Great return policy... :). The Quantum people were very unhelpful. I will buy factory for next pump when this one dies. Thanks for the advice everyone.






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#26 ·
Looks like I got it. Amazon knock off pump (Exactly the same as the Quantum) primed and is holding 57Psi. Im going to idle it for an hour. All the Quantum pumps (3) prior to this failed. Bought them on amazon. Great return policy... :). The Quantum people were very unhelpful. I will buy factory for next pump when this one dies. Thanks for the advice everyone.






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Just so you know that the main reason for fuel pump failure is running low on gas and it gets to hot .
I read that in a article and saw it first hand as a truck was run low on gas and it quit and after putting more gas in it still wouldn't start and it was the fuel pump quit.
 
#30 ·
I just came on to see what was going on with Quantum as I am having the same issue. 2014 Sportsman and the OEM pump quit last month. It started sputtering and when throttle was applied, it would die. Did pressure test and it was not making hardly any pressure. Ordered the Quantum after reading up on them and people here made it sound like once I buy it, I would never have to worry about it again. Well, it ran less than 5 hours and stopped. No motor, no pressure nothing. I still had my old OEM sitting on the bench, to see if the circuit was good it put it back on. It spun right up and delivered fuel. Pull it again, put the "new" quantum back on and nothing. No motor noise at all. Completely dead.

I requested a replacement from Quantum and received it about a week later. Put it in and ran like it should. This time I got less than an hour on it before it died. I just now pulled it, put my old OEM back on and again it spun up like it should. Put the "Newest" pump back on and still nothing. No motor sound.

So frustrating.

So to answer some questions that I see a lot of people ask the OP. Yes, this was from Quantum directly. Not Amazon. Gas is almost topped off. I never allow my tank to get less than a 1/4 low. Even in my cars I start looking for a fuel station when it drops below 1/2. This is just a carry over from 22 years in LE. I looked for contaminants in the fuel and on the screen but it is clean. I also checked the vent line to ensure it is venting and that there are no obstructions.

At this point, I feel like I would get better miles to the dollar with some knockoff off of amazon. All balls pump is looking good also, but I am just really tired of this thing going down because of inferior parts.
 
#32 · (Edited)
I just came on to see what was going on with Quantum as I am having the same issue. 2014 Sportsman and the OEM pump quit last month. It started sputtering and when throttle was applied, it would die. Did pressure test and it was not making hardly any pressure. Ordered the Quantum after reading up on them and people here made it sound like once I buy it, I would never have to worry about it again. Well, it ran less than 5 hours and stopped. No motor, no pressure nothing. I still had my old OEM sitting on the bench, to see if the circuit was good it put it back on. It spun right up and delivered fuel. Pull it again, put the "new" quantum back on and nothing. No motor noise at all. Completely dead.

I requested a replacement from Quantum and received it about a week later. Put it in and ran like it should. This time I got less than an hour on it before it died. I just now pulled it, put my old OEM back on and again it spun up like it should. Put the "Newest" pump back on and still nothing. No motor sound.

So frustrating.

So to answer some questions that I see a lot of people ask the OP. Yes, this was from Quantum directly. Not Amazon. Gas is almost topped off. I never allow my tank to get less than a 1/4 low. Even in my cars I start looking for a fuel station when it drops below 1/2. This is just a carry over from 22 years in LE. I looked for contaminants in the fuel and on the screen but it is clean. I also checked the vent line to ensure it is venting and that there are no obstructions.

At this point, I feel like I would get better miles to the dollar with some knockoff off of amazon. All balls pump is looking good also, but I am just really tired of this thing going down because of inferior parts.
Sometimes I guess you can get a bad one, did you get the kit or the drop-in version? My pump went out in November of '22 ordered the drop-in version worked like a champ for a week or so then my fuel gauge disappeared, used the lifetime warranty and got another one, while waiting for delivery I realized I had a bad float I had the wafer style float that snapped in, the float had a tiny pin hole in it and filled up with fuel and wouldn't float I used my old float then all was good now I have a Quantum pump sitting on the shelf ready to be dropped in. Don't give up on Quantum!!!!!! Btw replacement pump was $15.00 and that was for shipping.

My suggestion is don't give up on Quantum do a Search on Quantum in the Community Search guarantee you'll only find good comments.
 
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#36 ·
I just replaced the fuel pump last week with OEM after having issues with 2 quantum pumps. Ordered direct from high flow fuel....the first pump last about 2 hours. The sent me replacement, and that one didn't even make it an hour. Ran OK intermittently then started to die off, sounded like the engine was knocking and about to rattle itself apart. Checked pressure and was about 25psi.
 
#37 ·
Did you order the pump only or the entire drop-in unit? It's possibly you had a bad component other than the fuel pump.
When I replaced my fuel pump, I got a bad float. The float had a pin hole it was the biscuit type float and the fuel level didn't register on the display, I called Quantum, and they told me to use the return procedure at the bottom of the page I filled out the form it's very important to keep your paperwork order# etc. New pump was sitting on my front porch 4 days later. (Quantum is in California I live in North Carolina shipping was swift) I removed old float from my original Polaris made pump and installed on Quantum, now I have a spare pump sitting on shelf.
 
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#38 ·
I have had 2 OEM fuel pump failed at about 800 miles on Kodiak 700 EPS and Scrambler XP1000 S.
I replaced both with Quantum fuel pump and both are running fine and I'm the kind of guy that would upgrade anything to make my ride has worry free has possible and putting in a $500 OEM pump is not something I would do.
Till something else comes along that is proven to be better than Quantum fuel pump I'm sticking with Quantum.