Fuel Pump POWER SUPPLY problem - FIXED!!!!!

    Having a little trouble here, I was riding my bike (with the petcock off, thought it was on) and the bike stalled out, I realized the problem, switched the petcock on and the bike still would not start. So I thought it was the fuel pump, and I disconnected the fuel line from the pump to the carbs and nothing came out when trying to start it, so I bought a new fuel pump and the same thing still happens.

Today I hooked up a test light to the negative battery cable and tried touching each of the 2 prongs from the fuel pump wiring harness and I didn't get anything, I even tried it when trying to start the bike and nothing lit up. Everything else on the bike works, headlights, etc etc. I took apart as many wiring harnesses as I could, sprayed contact cleaner and used a little electrical grease, connected everything and even cleaned the ground under the fuel tank, NOTHING!

Needless to say I am getting pretty damn frustrated here, any ideas?!?!?!?!?

Exact same thing happened to me last fall.  The wiring harness went bad that goes to the fuel pump.  Since my harness is a tangled mess I cant tell you what wire to use, but I hooked into one that was providing voltage when the motor was running.  Ghetto fabulous?  perhaps but it works.

I tested the connectors where the fuel pump plugs into, so there must be a problem in the MAIN wiring harness of the bike, I guess I should try and trace the wires down. 

test your fuel pump relay, that might be your problem. i dont have a diagram to look at but if you could get ahold of one, find your powers and grounds going into the relay, and jump your power to your pump. if it pumps then chances are its your relay that is bad.  good luck....

I hate to be a buzzkill here... but this is the point in the game where I usually just pony up the $50 to have somebody else give themselves a headache over finding the electrical gremlin in the birdsnest of 20 year old wiring... but hey, that's just me

yeah I'm with Big 10,  I do some wiring but I'd just take to the shop.

Hehheh, you guys give up quick, I'm gonna fix this damn thing myself. It's not like tracing a wire in a car harness, this is a little ass bike harness! I'll fix it and post what the problem is, I was just looking for some ideas.

Oldschool,
    same thing happended to mine, and it was the relay that connects to the fuel pump.  The way it is designed to work is if the bike goes over the indicated redline on the tach, it cuts out the fuel pump.  I just bypassed the relay on mine.  And everything has been fine.  The same relay also went bad on my ols Shadow and I just bypassed that one also.  Hope that helps.
    Kcityrider

Is there a way to reset the "Fuel Cut Relay"?, According to the wiring diagram in my clymer manual there is a fuel cut relay. Anyone know where it's located? Cant seem to find that though.

There is no way to reset the relay, and it is located under the gas tank.  When you take your tank off you will notice directly infront of where the rear bolt holds the tank a rubber setup that holds some electrical wires in the holder is a black box about 1 1/2 inch by 3/4 inch.  It has a connector that has 3 prongs in it.  That box is your fuel pump cut out relay.
    Kcityrider

hmm, I'll take a look when I get home, so when that relay trips you have to replace the relay?

Yes, I just never replaced mine, so I do not know how much it is going to cost you.  I will keep checking to see if you have anymore questions.
     Kcityrider

I jumped the 2 black wires that go to the fuel cut off relay, but the pump starts running as soon as i turn the accessory on, normally the fuel pump kicks in when trying to start it. I really don't want the pump running like that when it's not supposed to. So I guess I need to replace the relay for the bike to operate to factory specs correct?

Does this relay really trip when the bike is taken past redline? If that's the case I also worry if I am in the middle of nowhere and miss a shift and trip this relay again. I couldn't find anything about this redline situation in my Cylmer manual. Any input is appreciated!

Your fuel pump should run whenever the bike is on, long before you start it, it needs to pressurize the fuel system and as soon as the key is on it should fire up.
Do you have a DMM? (digital multi meter)
Do you know how to use it?
If you have one and know how to use it the manual will tell you everything you need to track down the problem.
A test light will not tell you enough about the circuit to know if all is well, throw it away.
www.the12volt.com has very good instructions for beginers in electricity on how to use a dmm, to how to troubleshoot, wire a relay, etc.
A simple test to see if a relay is working is to put power to terminal 86 and ground to terminal 85, if it clicks it works and you have a problem somewhere else. Possibly in the multitude of grounds that can corrode and cause intermittent or no operation.
A relay is nothing but an electromagnetic switch, meaning its just like a switch you flip, but electricity turns it on instead. They are used for higher current applications when a switch or smaller wire cannot support the higher current loads. Like your starter. The wiring to have the starter switch directly fire the starter would be at least 8 ga, possible 6 ga, to run from the battery to the switch to the starter. BY running a relay they can run very light small gauge wire like 18-20 to the switch and have it control a relay to fire the starter. It ends up weighin about 1/3 less that way, but if you know knothing about electronics its waaaaay harder for you to deal with.
Unfortunately electronics are very hard to troubleshoot over a forum and I usually keep my mouth shut, however this should give you a starting place.
pm if you need more.
 

Since I don't have the cash for a relay right now ($48-$60), I have been trying to jump it (the 2 black wires togeather). But as soon as it starts, for like 1-2 seconds, it dies out, so I am assuming that yellow wire that goes into the relay (which goes to the tach and spark controller) must have to be hooked up somewhere too? I will have to test that yellow wire to see if it has any powering going through it to trip the relay.
 
What a useless relay. What have you other guys done with that yellow wire to get your bikes running without this stupid relay?!?!?

I am going to replace the relay eventually, I just want to ride right now!

The yellow wire that goes to the fuel cut relay get's power as soon as the key is switched on, just like everything else (main black wire that goes to the relay, so it seems all 3 should be jumped togeather, but I want to find out from someone that has done this successfully already before hooking it up (dont want to fry anything)

The relay will  does not trip, but cuts signal to the pump so the engine can not climb any higher in rpm.  Once the key is turned off then back on, it will supply the pump with the signal again.  I know the manual does not talk about it, I talked to my frien who has been a Honda Motorcycle for quite a long time, and he explained it to me, basically it is a basic form of a rev limiter.  Hope this helps.
     Kcityrider

All this because the bike was run with the petcock off, died at the end of the street (probably from running out of fuel in the bowls) and BAM, cant get the damn thing running again.
 
I guess I should see if the carbs need cleaning, the plugs and all filters are BRAND new, less than 100 miles on everything. I doubt the gas "went bad" in the 3 weeks it has been sitting for but ill change that as well.

Fixed the problem(s) (yes, 2 things here). 1. The fuel pump cut relay was bad, and jumping it did work (the 2 black wires). I didn't need the fuel pump I bought, but hey, now I have a spare.

The main problem was this: Remember when I said my tank had a ton of rust in it and I sealed it? Well, whenever I drove it and stopped, the extra dissolved rust that was in the fuel would sit in the bowls of the carbs and apprently build up, and when I ran the bike dry with the petcock off, it sucked all that crap in. When my roommate and I took apart the carbs, 2 of the pilot jets were completely clogged and the others you could barely see through. My Clymer manual was very good in terms of directions to clean the carbs, but we had a little work putting them back togeather because the main rail they attach to bends easily and there are these little springs for the carb syncing that we were putting in on the wrong side of the throttle arms which was keeping the intake flaps partially open, but it was easy to see that I just installed them on the wrong side.

The bike runs smooth and starts right up now. All I have to do is readjust the throttle (take the tank, airbox off ect) because it's not snapping back after I let it go and I did lubricate the throttle cables.

ALMOST there!