Posted this in the EVO section also, thought someone here might be able to advise me....

Just got my 97 Road King with EFI. When I drove it home I didn't notice any noise at all. Now I can hear the fuel pump (I'm pretty sure) high pitch whine all the time, not just when I first turn the ignition switch on. I can't hear it, obviously, when I'm going down the road but as soon as I slow down down to stop I can start hearing it.

The only thing I've done since I brought it home is fill the tank with premium and put a little Seafoam in it. Any idea what could cause this? Fuel filter need changing? Fuel pump going out? I don't want this to turn into something that strands me.

 

with the bike off open up you fuel cap and look inside with a flashlight (not a lighter) then turn the key on and if you see spray or splashing then you have a ruptured fuel line. Probably caused by rubbing against the inside of the tank. If so go to napa and get a foot of submersible fuel line made by Gates or Napa. Hope this helps.

 

OK I looked in the tank while turning on the ignition and the only thing I saw was a few small ripples on the surface of the gas and at the bottom of the tank I could see the fuel "moving around" some. Is this normal?

 

It could be. The factory fuel lines are prety flimbsy and shake a little. Time to get a small inspection mirror and look a little deeper in there.

 

If its not a bad hose my money is on a wore out pressure regulator. If its bad or week it cant hold the fuel pressure that the pump is putting out and it will dump it back into the tank. The lower the fuel level the better you can see whats going on in there. Some one else chime in if you got a better idea.

 

Maybe I should just do a changeout of the filter and regulator as a preventative maintenance item then I can look at the lines in there too. Is the regulator part of the same assembly the filter is part of (in the tank?)? BTW I do have the Service Manual for the bike.

 

Yep. That's what id do. Piece of mind. Spent two weeks thinking my clutch was slipping but it was a dirty fuel filter. Just take a good look at your fuel lines.

 

This bike is a magnetti marelli which has a 45 psi running, the pressure regulator is located on the induction module and is always working sending fuel back to the tank. This is more than likely your ripples. The magnetti marelli pump is quite noisy in comparison to the newer Delphi pumps and wouldn't jump the gun in thinking something is wrong just yet.

 

Funny thing is, is that when I drove it home after buying it from the PO I don't remember it whining at all. I'll definitely monitor it to see if it gets worse or changes pitch drastically.

 

I would still replace the filter and have a look around in there. I know the Delphi equipped models had some fuel line issues.