Lower fuel pump un-primes, again

[Kachess]

Had it happen again, yesterday. A few weeks a go, up in Revelstoke in waist high powder, I had my lower fuel pump un-prime numerous times. I later found my airbox half off and attributed it to that. Yesterday I had it happen again. Airbox was tight. We were in very, very deep snow all day, really hitting it hard. One time after shutting off my sled to help dig out, I restarted it, went about 100 yards, and started running on 2. I would really gun it and it would fire back up, but would let off and it would go back to two. Finally I could not get it to fire on all four and while idling, sucked on the lower fuel pump outlet and got it pumping again. It ran ok the rest of the day. Today I'm going to check the lower fuel pickup in the tank and replace the fuel pump with one I took off our turbo. My son's sled, with 5k fewer miles, has had the same issue a couple of times. Always the lower fuel pump, always when bashing in deep snow. We ride with six other Tons, regularly, that have never have the issue. I'm stumped. I wish there was a cheap, reliable, light, electric pump I could replace it with. The one on my turbo weighs a ton.

 

[rx-hi]

Kachess sounds like you should pull the exauhst manifold off and put on your turbo. We certainly have the snow for it. I have the mechanical pumps from my 03 as mc-x just runs the elec pump. You are welcome to try them to see if it is your lower pump. That would be frustrating in any conditions but especially in the snow we have been having! Lot of spots 2 cylinders will not get you out.

 

[Kachess]

Man, I want to get the turbo up again. Finally have the snow to really test it and there it sits, waiting for parts. I pulled off the pumps on our stock tons and you can blow back through the lower one, but not the upper. Tried the pumps I took off the turbo and you can't blow back through either. Tried my kids sled and sure enough, you can blow back through the lower but not the upper. The check valves must not be working in both lower pumps. I swapped out the bad pumps and fired up the sleds. Gas now shoots out the lower pumps where it spit out before. So why are there two separate gas pickups, anyway? It's not like it'll run on two cylinders very well if one is plugged.