Fuel delivery problems?
alligator clips and wire. The pump only has two terminals. Power and ground, as it is mounted in plastic. I hooked them up while the pump was immersed in a bucket of water. No sparks to worry about. As soon as I touched the wire to the positive on the battery, the pump did its thing, and pumped the water .I don't yet have the means to test the line pressure, but am looking into that. Fair questions. Ones I've already asked myself.
If you get a fuel pressure gauge, put it in-line at the tank disconnect, then run the bike and observe the pressure..... That will tell you if all within the tank is working properly.
Once you know all the tank internals are working properly, you can start to look elsewhere....
If you are showing/maintaining 58-60psi for Harley Delphi fuel injection you are golden, 47-49psi for early Harley MM EFI.
Good luck with your diagnosis and keep us posted on your progress...
Last edited by hattitude; Jul 22, 2023 at 12:24 PM.
Well, all is well again. I have no idea why. I removed EVERYTHING from the tank, and I mean EVERYTHING. Went through it all with the proverbial fine toothed comb. Found nothing that was visible. Blew through every hose and opening. Took everything apart. Put it all back together being very meticulous. Dumped a little gas in the otherwise empty tank, and it fired right off. Not very smooth, though. Like one cylinder was missing a little at idle. ( brand new properly gapped plugs already installed) But cracking the throttle, it came to life like it always has before. So I dumped a bottle of injector cleaner in the tank, and ran it for a bit to get the cleaner in the lines. Did that several times. Started idling a bit better, so off on a ride I went. It got progressively better as I rode, despite the 98 degree temps. I wish I could say I did such and such and fixed it, but I think just a bit of crap got in the lines when the fuel line ruptured. Pain in the ***, but at least the bike was in my garage to work on it. Thanks all for your suggestions.
Well, all is well again. I have no idea why. I removed EVERYTHING from the tank, and I mean EVERYTHING. Went through it all with the proverbial fine toothed comb. Found nothing that was visible. Blew through every hose and opening. Took everything apart. Put it all back together being very meticulous. Dumped a little gas in the otherwise empty tank, and it fired right off. Not very smooth, though. Like one cylinder was missing a little at idle. ( brand new properly gapped plugs already installed) But cracking the throttle, it came to life like it always has before. So I dumped a bottle of injector cleaner in the tank, and ran it for a bit to get the cleaner in the lines. Did that several times. Started idling a bit better, so off on a ride I went. It got progressively better as I rode, despite the 98 degree temps. I wish I could say I did such and such and fixed it, but I think just a bit of crap got in the lines when the fuel line ruptured. Pain in the ***, but at least the bike was in my garage to work on it. Thanks all for your suggestions.
In any case, glad it's back up and running... enjoy...!
Okay. Bike is an '08 FLHT with a cubic buttload of miles on it. Stage 2, with a Power Commander 6. Riding a few days back, bike ran fine. Plenty of power, responsive throttle. Bike bucked once and the engine stopped. Half tank of fuel. Good battery, etc. Get the bike home, pull the tank top cover off to check for a bad hose. Sure enough, one was blown out. Fuel pump was aftermarket, so a bit questionable as to reliability. Replaced it with a factory fuel pump. Installed new filter. ( old one still looked pretty good).Bike starts and idles. As soon as I blip the throttle, it dies, like out of fuel. Then hard to start, and doesn't idle very well. I've removed the main fuel line (the one with the quick release fitting) and determined there was no blockage. Removed the fuel pump again, checked THOSE hoses, could find no holes or blockages. The bottom fuel pump filter is almost new. Housing for the filter is good, no cracks, and is seated properly. When I disconnected the fuel line at the quick disconnect, there was pressure. And when I disconnected the hose from that point to the fuel pump, there was also pressure. I checked the wiring for the throttle body, and found no problems. Disconnected the PC6, plugged in the stock ecm, no difference at all. Blip the throttle, and it quits. At a bit of a loss as to what to check next. Open to constructive suggestions here.
Last edited by danaezabail; Aug 2, 2023 at 11:09 AM.
My guess is, you had residual water in the fuel pump from your test. Once it purged itself from the system, it now works correctly. I understand why you used water to test, but I've always tested with fuel to prevent getting water in the system (cars, never done that on a bike). I just use long leads to keep the power and any sparks far from the fuel.
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