[boatwire]

Has anyone (else) emptied the fuel tank by disconnecting the fuel line at an injector and keying on the fuel pump?

 

[Furious_Mike]

Nope I just did it the hard way….. lifted tank up and disconnected hose there…. Yeah it was a lot of fun trying not to get the gas everywhere…. 😂

 

[WI_Hedgehog]

Running the fuel pump dry can overheat it as the fuel is used to cool it. I just stuck a hose in the tank to siphon most of the gas out and called it good at "most."

 

[FURY-S1]

I had to clean rust out of the tank on the Stateline I bought last summer. Tank was removed from bike which is not difficult and it was drained, cleaned, drained, primed, drained and then reinstalled. Just be careful, they dent easily when they aren't attached to anything.

p.s. if I can do it anyone can.

 

[boatwire]

Here's the real question: When you get ready to ride, and turn the key to RUN position, you can hear the fuel pump turn ON and after a second or two it turns OFF. What turns it OFF? Pressure limit switch? Timer? Electrical resistance/power change?

I disconnected the fuel line at the front injector and collected the fuel in clear glass bottles. I had to repeatedly turn key OFF/ON. My auto mechanic brain thought: Since the fuel line is disconnected the pump would run continually. WRONG!

 

[WI_Hedgehog]

If I understand correctly, the fuel pump relay is "on" when the ignition turn on, only for a few seconds, then it turns off. This builds enough pressure to start then engine but won't pump it all over the pavement if a fuel line is broken.

I think the starter solenoid might also energize the fuel pump.

After that the oil pressure switch powers the fuel pump. If oil pressure drops "too low" the engine fuel is cut.

I'm not sure if that's exactly how it works, it's only my basic understanding (which is quite possibly wrong).

 

[boatwire]

If I understand correctly, the fuel pump relay is "on" when the ignition turn on, only for a few seconds, then it turns off. This builds enough pressure to start then engine but won't pump it all over the pavement if a fuel line is broken.

I think the starter solenoid might also energize the fuel pump.

After that the oil pressure switch powers the fuel pump. If oil pressure drops "too low" the engine fuel is cut.

I'm not sure if that's exactly how it works, it's only my basic understanding (which is quite possibly wrong).

Thanks for the info...Much appreciated! I can understand the reasoning/logic of the pump's control circuit.

 

[WI_Hedgehog]

There's nothing stopping you from attaching a clip lead from the battery terminal to the fuel pump relay or fuel pump. It's probably going to cause other issues, but for those who do it that seems to be how its done.

 

[FG Steve]

If it were me, I would consider using another method (siphon pump?) for most of the fuel and the fuel pump just for the "dregs."

 

[boss1138]

Nope I just did it the hard way….. lifted tank up and disconnected hose there…. Yeah it was a lot of fun trying not to get the gas everywhere…. 😂

This is what I've done... disconnected the hose and quickly connected a different hose to it that runs to a fuel tank. Just make sure there are no bends or it'll come back up the hose of course.

Lately though I've just removed the gas cap and turned the tank over and rested it on a receptacle. I guess anyone with an actually good paintjob wouldn't want to do that, though

 

[DOCmjj]

Get a 2-3 foot long piece of fuel line for draining the tank and a 5 gallon gas can put one end of the hose into the gas can next to the bike
now remove the drivers seat & unbolt the rear tank bolt and nut and remove them
then lift the rear part of hoses underneath the tank are higher than the rest of the tank pull off the fuel line and run the drainage hose up between the frame attach the drainage line to the removed line
set the tank back down & remove the filler cap

 

[DOCmjj]

This got figured out after I drained it out of the filler cap hole