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electrical gremlin

summ8rmk

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yakima, wa.
The EGT reference was for while riding, to see if it was dumping extra fuel and abnormally low EGT.
I forgot u put in aftermarket regulator.

Sent it
 

matt159

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Thinking it might be the quantum regulator I stuck in. It didn't go in easily with the double o-rings. I'm wondering if I caused it to bind or seat crooked or something.
I left the larger o-ring off when i put mine in. I'm surprised you got the plastic retainer to snap back on at all with the extra o-ring still there. If that doesn't fix it, the other suggestions made sound on target: something before the fuel pump possibly causing restriction. Friend of mine mentioned that black section of fuel line below his pump broke down and was "spongy/sticky." It was collapsing & restricting his fuel flow. It is not your normal high pressure fuel line if you need to replace it. Need special line that is rated for immersion in fuel. If pressure is all good for a while but seems to fall off once the fuel pump has been running for a while, it's possible that the fuel pump has been failing also. Any shiny gold (brass) flakes in the bottom of your fuel tank? Always lots of possibilities unfortunately.
 

kidwoo

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12v on the pump will drive it up to mid/high 40s then settles to 35 as soon as I remove the juice.

Started it up and it hangs out at 35 while running still. Pump connector had a little bit of corrosion on it. I cleaned it up a little but no change.

I ran it without the hood on for a while to get some fuel in the tank, then disconnected the electrical from the pump to try and get a reading from the harness. With it running I can't get a voltage reading. I may end up replacing the plug. This is weird.

edit: pulled the pump and checked lines, screens etc. Hoses feel fine. The larger o-ring had slipped down out of the seat from the pressure regulator. I pulled it out.

Sled is still idling at about 30 psi with the hood off but it's holding pressure much longer after shutting it off. I called quantum and they're sending me another regulator to rule it out.

I actually do have some gold flakes in the tank but that could also be from the last pump that was in there. This one only has a few hundred miles on it.
 
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sno*jet

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whacky fuel and extended WOT sessions til she overheats? what could go wrong?! LOL
 

sno*jet

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ive never seen one overheat in 4', been breaking trails in like that for 27 years. somethins up, a combination of issues you got goin there
 

kidwoo

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ive never seen one overheat in 4', been breaking trails in like that for 27 years. somethins up, a combination of issues you got goin there

For sure.

When I say overheat, I don't mean while running, I'm talking about the heat soak after finally being able to stop. These water sensors seem to consistently read about 20 deg high but it was reading 140+ while completely submarine bobbing in blower. Never triggered the light but when I could get a chance to swipe the gauge for a quick read that's what I saw, which is higher than your average deep day. But it's been a few of those days where you have to keep it pinned literally just to stay afloat on a 3% road grade.
 

sno*jet

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oh i thought you said literally overheating like blinking light while breaking trail, didnt sound right. I keep mine away from other cats while in storage, drop a vitamin C in the tank before riding, I dont think mines gonna catch this, you might be screwed bro. Quarentine that chit!
 

kidwoo

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Final season update: After rewiring the fuel pump plug, changing out the coolant sensor (did nothing from what I can tell, still reads high), installing some different very low mile injectors that I bought used, replacing some reeds that barely showed any wear on 2 petals.........I think I might have it.

Power to the pump is consistent now at 16ish V. I'm thinking that's what the system runs at because everything else on the harness is 13.5-14v as it should be. I have another regulator I may throw in just to see but the more people I talk to getting a reading off the pump, that seems common. Running in warm weather it's running stronger than it has since it was new.

Heat soaking will require a few pulls but fuel pressure still builds and it will start. The things I think that matter are the following:

1. rerouting the fuel line
2. Getting a better connection on the fuel pump plug
3. injectors that are probably just cleaner than my old ones


Reeds, air temp relocate, stator, voltage regulator, artificially high reading water temp getting replaced, stator, regulator, harness had nothing to do with anything since none of those fixed the issue.


When I originally replaced the main harness and fuel pump last year I do remember the sled running better and it took several rides before the problem started again. I think that's because the fuel pump plug got a better connection, but the design still lent itself to corrosion and possible loss of good connection with heat. But the start and burble/start and die/just not start problem is I think a product of both vaporizing fuel in the line, and a pump that doesn't have enough juice to push past the vaporized fuel in the line. Again supported by the fact that they'll usually start once things have cooled down. Doesn't hurt to replace the fuel line regulator. The quantum one seems to work more consistently and hold pressure longer than my (probably worn out) stock one.

Unfortunately I won't really know until next year after staying pinned for long periods of time with snow getting in everything again but right now I think I may have finally gotten it figured out. When this started a few years ago, I do remember someone here saying to replace that plug to the fuel pump. I wish I'd listened to them earlier.
 
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Dec 30, 2019
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Final season update: After rewiring the fuel pump plug, changing out the coolant sensor (did nothing from what I can tell, still reads high), installing some different very low mile injectors that I bought used, replacing some reeds that barely showed any wear on 2 petals.........I think I might have it.

Power to the pump is consistent now at 16ish V. I'm thinking that's what the system runs at because everything else on the harness is 13.5-14v as it should be. I have another regulator I may throw in just to see but the more people I talk to getting a reading off the pump, that seems common. Running in warm weather it's running stronger than it has since it was new.

Heat soaking will require a few pulls but fuel pressure still builds and it will start. The things I think that matter are the following:

1. rerouting the fuel line
2. Getting a better connection on the fuel pump plug
3. injectors that are probably just cleaner than my old ones


Reeds, air temp relocate, stator, voltage regulator, artificially high reading water temp getting replaced had nothing to do with anything since most of those didn't fix the issue.


When I originally replaced the main harness and fuel pump last year I do remember the sled running better and it took several rides before the problem started again. I think that's because the fuel pump plug got a better connection, but the design still lent itself to corrosion and possible loss of good connection with heat. But the start and burble, start and die, just not start is I think a product of both vaporizing fuel in the line, and a pump that doesn't have enough juice to push past the vaporized fuel in the line. Again supported by the fact that they'll usually start once things have cooled down.

Unfortunately I won't really know until next year after staying pinned for long periods of time with snow getting in everything again but right now I think I may have finally gotten it figured out. When this started a few years ago, I do remember someone here saying to replace that plug to the fuel pump. I wish I'd listened to them earlier.
I did al
 
2
Dec 30, 2019
5
1
3
49
Bc
Final season update: After rewiring the fuel pump plug, changing out the coolant sensor (did nothing from what I can tell, still reads high), installing some different very low mile injectors that I bought used, replacing some reeds that barely showed any wear on 2 petals.........I think I might have it.

Power to the pump is consistent now at 16ish V. I'm thinking that's what the system runs at because everything else on the harness is 13.5-14v as it should be. I have another regulator I may throw in just to see but the more people I talk to getting a reading off the pump, that seems common. Running in warm weather it's running stronger than it has since it was new.

Heat soaking will require a few pulls but fuel pressure still builds and it will start. The things I think that matter are the following:

1. rerouting the fuel line
2. Getting a better connection on the fuel pump plug
3. injectors that are probably just cleaner than my old ones


Reeds, air temp relocate, stator, voltage regulator, artificially high reading water temp getting replaced had nothing to do with anything since most of those didn't fix the issue.


When I originally replaced the main harness and fuel pump last year I do remember the sled running better and it took several rides before the problem started again. I think that's because the fuel pump plug got a better connection, but the design still lent itself to corrosion and possible loss of good connection with heat. But the start and burble, start and die, just not start is I think a product of both vaporizing fuel in the line, and a pump that doesn't have enough juice to push past the vaporized fuel in the line. Again supported by the fact that they'll usually start once things have cooled down.

Unfortunately I won't really know until next year after staying pinned for long periods of time with snow getting in everything again but right now I think I may have finally gotten it figured out. When this started a few years ago, I do remember someone here saying to replace that plug to the fuel pump. I wish I'd listened to them earlier.
I had all the same things happen and pretty much did all the same things as you except for one I relocated the air intake temperature sensor or mass airflow sensor which ever you wanna call it right behind you ignition key relocated down to the air intake with the intake on the hood goes in front of the snowmobile right before the carbs and change the fuel tank and all the pods and fuel pump inside the tank and I have never had a problem cents but before that it was very intermittent left me stranded many times And now is all good
 

kidwoo

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I did relocate the air temp sensor to the air box. With a new sensor at that.

First ride out the problem still continued.
 
2
Dec 30, 2019
5
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Bc
I had all the same things happen and pretty much did all the same things as you except for one I relocated the air intake temperature sensor or mass airflow sensor which ever you wanna call it right behind you ignition key relocated down to the air intake with the intake on the hood goes in front of the snowmobile right before the carbs and change the fuel tank and all the pods and fuel pump inside the tank and I have never had a problem cents but before that it was very intermittent left me stranded many times And now is all good
What I did find on the inside of the tank is that the hoses were not connected to the bottom of the fuel pump very well and the pick ups for the fuel on the bottom of the tank were stuck and plugged with crud and every since l replaced it I have never had a problem since they Were sucking air causing me to run out of fuel
 
N
Jul 23, 2008
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Is this the comprehensive "how to fix hot restart issue" thread? I'm having the same problem as kidwoo - only difference is I haven't gone down the rabbit hole of replacing parts yet, and letting my sled cool down doesn't help. I can leave it for hours/days after shutting it down hot and next startup will have these issues. First thing to check on my list is reeds, followed by fuel pump connector. Everything in the fuel system ohms out correctly.
 
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