502 mag mpi cutting out
#42
#43
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So I took the boat out today, same deal. Took scanner with me, and fuel psi tester. When I get up and running and start getting around 4,000 rpm and above I lose about around 20psi, fuel pressure will fall off to mide 20’s. I’ll attached the video I took, can’t watch the pressure just suddenly fall off, and that’s when the boat starts breaking up. So I believe I’m looking at fuel pump issue, or reg. Both of which I’ll probably replace since I’m down there.
Can I replace just the fuel pump on the fuel cooler? I’ve read both thing you can replace just the pump, others says pump and cooler?
video posted few posts down
Can I replace just the fuel pump on the fuel cooler? I’ve read both thing you can replace just the pump, others says pump and cooler?
video posted few posts down
Last edited by Bstocky; 09-04-2023 at 09:58 AM.
#45
Registered
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go out and run the boat again,but this time w/ a separate gas container.eliminate all the fuel hose in your boat.
#46
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92nsx (10-10-2023)
#47
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I only have about 20” of rubber fuel hose, from tank 90° to my shut off valve and another 10” of hose from shut off to the filter housing. From filter housing it’s hard line hose assembly
#49
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Also pulled the sending unit out, looked in the tank and pick up, which is just a stainless tube straight down. When I had the fuel hose off the barb I feed a long zip tie through until I could see it poking out in the bottom of the pickup in the tank. Pulled the full hose off the bard at the filter housing a blew a little air back into the tank, had the wife Verify air was coming out the breather vent as well.
#50
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Looks like it could be creating a vacuum in the tank, have you checked the vent hose to be sure its clear, loosen the gas cap while running to see if it picks back up, maybe you covered this I just scanned the post