fuel pump keeps whining and whining and whining

[oldfieldcycles]

never had an issue with the fuel pump whine that ive heard about. When i went to drive the my 95 k1100 after a few months of not being driven, turns out the bike caught the disease. I then read every post i could on the subject, saw that many people say that its just part of owning one of these bikes. I checked all the lines, no visible issues. the overflow lines are clear, no suction in the tank. the pump whines when the tank is full or almost empty. i replaced the fuel filter and then finally bought an replacement fuel pump(ebay special) not an OEM model. no change at all. i replaced the fuel, ran injector cleaner in the fuel. the whine is extremely loud, makes me not drive the bike. i read somewhere that the fuel pressure regulator could be the issue and the constant whine is the fuel bypassing the valve due to back pressure. does this make sense?

[The Mighty Gryphon]

Is the plastic holder for the pump tight in the plate where the pump is mounted?  Can you wiggle the pump? 

I had the pump out of one of my bikes and didn't put it back with the tabs properly snapped in.  Made a horrible racket.

You can disconnect the return line at the tank and have it drain into a can.  That will tell you if there is an issue with the check valve on the return line into the tank.

You can also disconnect the return line at the injector rail and let it drain into a can.  That bypasses the regulator and will tell you if that is the problem.

Does the noise happen all the time, or just when the engine is running.  If it's only when the engine is running it could be the regulator and the vacuum from cylinder #4.

[Laitch]

Does the noise happen all the time, or just when the engine is running.

[Martin]

A crimped or restricted FPR return line can make the pump noisier. On really hot days before I insulated the lines and the bottom of the tank and fitted a fuel rail heat shield the pump noise would increase. But not as bad as a crimped line.
Regards Martin.

[Scott_]

Does the noise happen all the time, or just when the engine is running.  If it's only when the engine is running it could be the regulator and the vacuum from cylinder #4.

A 95 1100, doesn't use vacuum for the FPR, it is spring loaded.

[oldfieldcycles]

the pump primes(kind of loudly) when the key is turned then there is no noise until the motor is running. once its running, it whines constantly, hot or cold, full or low tank. ill check the lines and the FPR. can the FPR be flushed in some way or would it need to be replaced if it is the problem?

[volador]

FPR spring rate is calibrated to the fuel systems nominal operating pressure of 36 psi/2.5 bar.
A shot of compressed air in that psi range or slightly higher to the side port of the FPR may loosen a stuck valve.

A gauge reading what the fuel delivery pressure is would narrow down whether or not FPR is at fault.

[Laitch]

constantly, hot or cold, full or low tank. ill check the lines and the FPR. can the FPR be flushed in some way or would it need to be replaced if it is the problem?

Don't get ahead of yourself because time taken to hypothesize not only stalls action but diverts focus. Check the pressure first. If you could make a YouTube video of the noise and post a link to it here, we'd have a clearer sense if you're experiencing something extraordinary.