Fuel pump not running and fuse popping? help me out please?

I've been repainting some parts on my bike. I decided to gas it up and run it today while im working on the rear cowl. I noticed that the fuel pump does not run to suck any fuel out of the tank. Im pretty sure it hasnt since i have bought this bike.

I have pulled the pump and ran it off a 12v drill battery and determined that the fuel pump itself is good. I also have a fuse keep popping. its the one that says "IG CHG FUEL" 10 AMP. I replaced it a couple times to see what was happening. One i turned the key on, cranked it, let off. as i was looking at the fuse it pops. A second fuse i put in did not pop with the pump disconnected. so for now i have a circuit breaker in it. something seems to be shorting out briefly. The wiring diagram isnt easy to follow from the scanned in pdf shop manual. It says to check continuity between the blue wire at the fuel cut off relay and the ignition control unit. not sure what its referring to or where the ignition control unit is.

At no time have i heard or felt the pump run. Im thinking i might have something wrong with the fuel pump cut off relay? What i did do was prime the carbs up with the drill battery and run the engine.

What do you think i have bad here?

 

Damn fuses. You could always just stick a thick piece of wire in there.... JUST KIDDING DON'T DO THAT.

Many believe u don't need a fuel pump. Someone will chime in and agree. just as many will chime in to dis-agree.

 

Their relays fail more often than the pumps themselves. Do the relay bypass at its plug, then listen for pump clicks when the key is ON. NO clicks ?? Check fuse again. Try opening any float bowl drain screw to let out some fuel. Still no clicks, post up again, and we'll dive in farther......

Test the pump leads with your multimeter, and you should see about 4-6 ohms if the pump is good.

Check that the center shaft is free to move up about 10mm while you pull it, then spring back. if the shaft is stuck from corrosion after sitting for years or whatever, it will blow its fuse.

 

squirrelmman, is this the pumps internal relay that your talking about?i just measured 3 ohms across the pump while disconnected. i was messing with it earlier, i had some jumper wires from the battery direct to the pump. it pumps and then slows down to a stop(as if it had the carbs full and pressurized) i ran it the bike until it basically ran out of gas then i jumped it again and so on. then i was trying to get the bike to gravity feed, i need more gas and out of money...

 

that is exactly what mine was doing, run for 7-8 blocks, progressively getting weaker, til it died. Jumper it again, then the same thing. Thought I had my tank clean, but I was wrong, it was still plugging the main line out of the tank.
That being said, I'm not sure what is causing you to blow the fuse. The relay should be controlled by one of the spark units. I have seen methods to test this in other threads here, so you may want to do a search.

 

well all was well before. it sat for a few weeks while i redid my tank. it sprung a leak from the bottom seam. so i used evaporust and red-kote liner. then repainted it. what is really wierd is that i get to the pump, but under load(i used an LED foglight to put a load on it) the voltage would drop to 8 volts!?!? i think it has a bad wire but cant diagnose it. im thinkin about trying a different pump if i cant accomplish gravity.

 

Gravity will work but the tank needs to be full because the carbs are higher than the bottom half of the tankYou would probably have to bypass the pump as well for gravity to work

 

I ended up buying a mr gasket pump today, a 4 pin relay and a switch. I just have to figure out how i want to wire it.

 

So while you are playing with wires, get yourself a fuel shutoff solonoid because this may prevent a fuel hydrolock in the future and trust me it does happen

 

Norm, do you mean to prevent fuel from flooding the engine while parked/shutoff or overnight? i seen where someone said they had to shutoff the petcock when using these pumps. i was thinking about installing a ball valve post pump.

 

Couple of problems with fitting a ball valve, you have to remember to shut it off and there is nowhere you can fit it so that you can get to it easily. Solonoid valve is cheap and you don't have to remember it, turn the ignition off and the valve is shut. There is a post somewhere in the last week or so of a motor that locked up because the float needle valves didn't hold and I assume it bent a rod and now that motor is junk

 

On that bike you should be able to simply and easily turn the petcock to OFF without fretting about fuel flow when it's not running. Test it by disconnecting fuel line to pump.

I's not possible for fuel to flow to carbs with the stock pump in place and not powered. Only on bikes with vaccum-operated defective petcocks using gravity feed, no pump.

 

But in this case he is not fitting the stock pump so it is an unknown. Just refer back to the posts regarding "VFR getting the boot, new Ninga in the garage" I think for $20/30 cheap peace of mind