2006 Vulcan Nomad - Cranks over with no fuel, no spark

Discussion in 'The Garage' started by tntmo, Jul 28, 2019.

  1. tntmo

    tntmo Oops, I did it again.

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    Just picked up this project, figured it might be an easy fix. Just started troubleshooting it. Good battery voltage, engine cranks over fine.

    The fuel pump is not priming when you cycle the key or the engine kill switch. I have jumped the leads from the pump straight to the battery and the pump is working. The fuel pump relay clicks (very lightly), it has 12 VDC source power, 12VDC to the other terminal when the power is applied, but only .5VDC seems to be on the output side of it where it plugs into the fuel pump.

    I don't know if that has anything to do with the ignition side of things, but there is also no spark. I guess one thing at a time. I am thinking ground issues, but open to suggestions.

    Picture of this heavy metal/plastic.

    [​IMG]
    #1
  2. LuciferMutt

    LuciferMutt Rides slow bike slow

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    Check all the safety interlocks first -- sidestand, clutch switch, neutral switch.

    You should be able to unplug each switch, and jumper the connection in the plug to "fake" it.
    #2
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  3. tntmo

    tntmo Oops, I did it again.

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    I always see this as a suggestion, but every bike I have owned the safety switches cut ignition completely, meaning it wouldn’t even crank over. I will still check them, thanks.
    #3
  4. tntmo

    tntmo Oops, I did it again.

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    I can hear the DFI relay click when I turn on the key, but it sounds sort of weak. I removed it and tested it and it doesn't seem to be working, so I ordered one on Amazon.

    I got the new relay from Amazon, pretty quick since I ordered it on Sunday. I bench tested it and it passed. I installed it on the bike, no change. I then removed the vehicle down sensor. I removed it and pulled it out on the left side of the bike, installed the tank so I could hook up the ignition switch and low and behold the fuel pump started to work.

    The vehicle down sensor test in the manual failed, but I was still getting fuel pump priming. I checked spark at this point and none to be found still. Then after a few times the fuel pump didn't work again and I wasn't getting 12VDC source power to the vehicle down sensor. 1.5 VDC is all I was getting after turning the key on, I tested it at the 15 amp fuse.....12VDC before the key was turned on and 1.5 after.
    #4
  5. tntmo

    tntmo Oops, I did it again.

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    Reading wiring diagrams and shooting out the wires is a pain, but methodical procedures helps to figure it out. I traced all the wiring for the pump, it was driving me crazy. As soon as the key switch was turned on, voltage dropped to 1.5 or so. I don't know exactly what fixed it, but I did remove the 15 amp fuse and it was slightly corroded so I wire brushed the terminals and now we're back to fuel pump working.

    So I believe I was testing the vehicle down sensor incorrectly, it does seem to pass the test parameters. The fuel pump cycles, I have done it about 20 times now consistently.

    So if that's working, now I'm just working on getting spark to the darn thing. I did remove the ignition switch, took it apart and cleaned it. I also removed the kill switch and cleaned it. More to come......
    #5
  6. dtysdalx2

    dtysdalx2 Knowledge is horsepower

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    Usually the ignition coils get 12V from the battery when all the interlocks are "made" or closed.

    So, there should be 12V to the coils when you turn the key on.
    #6
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  7. tntmo

    tntmo Oops, I did it again.

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    Well, I spent the entire day digging through the manual, reading wires and scratching my head trying to figure this thing out. I don't have all the equipment listed in the shop manual, so could only test so much. I did a resistance test on the coils and while doing that I decided to trim back a tiny bit on the spark plug boot end, unscrewing the cap, cutting off maybe 1/4" and screwing them back on.

    After I did that, I tapped the start button and the bike coughed to life! I don't believe that had anything to do with it. I had the bike on the charger, and maybe it had reached enough voltage to make everything work. That's my hypothesis anyway. I came to that conclusion because I removed the charger to install the tank/seat/etc so that I could test the bike and it didn't start after doing that. I again hooked up the charger and after a couple minutes it started.

    I got the bike through all the gears and it appears to work fine. A bit of hesitation but the fuel smelled old, so maybe that's it. After stopping the bike back at the garage it starts right back up, but if I let it sit for just a few minutes it will crank over but not start.

    Everything I have read says these bikes are super picky about having solid voltage from the battery. I guess that's been the no spark issue all along? Anyway, here's to getting a project running for just a couple bucks! Now it's time to detail it and make it shine.
    #7
  8. VX Rider

    VX Rider Long timer

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    and a new battery
    #8
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  9. tntmo

    tntmo Oops, I did it again.

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    Already on order! Amazing, it cranks over pretty good but absolutely won’t start. The battery can turn it over multiple tries. Just low enough not to signal the ECU to fire. Fuel injection is great except for things like that.
    #9
  10. tntmo

    tntmo Oops, I did it again.

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    I ordered a new battery, figuring with solid voltage the bike should start up. I added the electrolyte and trickle charged the battery as per the manufacturers specification, installed it and the bike cranks over just fine but still doesn't start. Once I put the battery charger on, it fires right up. It will start off the battery for about five seconds after I shut it off, but any longer than that and it just cranks and cranks with no fire. The fuel pump is cycling fine.

    Anyone??
    #10
  11. VX Rider

    VX Rider Long timer

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    Sounds like loose, corroded wire somewhere in the system, it's causing too much resistance/voltage drop
    #11
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  12. tntmo

    tntmo Oops, I did it again.

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    My thoughts as well. Time to start cleaning connections. Grounds first I suppose.
    #12
  13. tntmo

    tntmo Oops, I did it again.

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    Here are my voltage numbers.

    12.7 VDC without the key on
    12.5 VDC with the key on
    11.6 VDC while cranking

    I have found that once the bike has started on the battery charger, I can turn the charger off and as long as I don't turn the key off it will start multiple times. As soon as I cycle the key one time, it won't start on the battery again.
    #13
  14. dtysdalx2

    dtysdalx2 Knowledge is horsepower

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    :scratch

    Sounds like a goofy Kawasaki safety thing. Bad contacts on one of the safety relays? Voltage drop = no fire.

    [​IMG]
    #14
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  15. tntmo

    tntmo Oops, I did it again.

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    Perhaps. It's just way odd that it will start on the battery after I get it going on the booster. I even left the key on for ten minutes with the lights all on, voltage dropped to under 12 and it started right up. Once I cycle the key, nope. I guess I need to drag a trailer with a generator and a battery booster? :rofl
    #15
  16. VX Rider

    VX Rider Long timer

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    Take ignition switch apart and clean it......dont lose the little springs
    #16
  17. tntmo

    tntmo Oops, I did it again.

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    Done it, twice now.
    #17
  18. VX Rider

    VX Rider Long timer

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    The you have a wire with corrosion under the insulation somewhere in the circuit
    #18
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  19. tntmo

    tntmo Oops, I did it again.

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    Yeah, I think there's an issue like that somewhere. What really gets me is how once it starts on the booster it will start again and again until I cycle the key switch. Makes me feel like there's a relay or something that gets powered on after it starts?
    #19
  20. VX Rider

    VX Rider Long timer

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    Trace your ignition circuit...find any and all relays...my local shop tested several components for me at parts department for no fee.
    Embarrassing to say the parts were all fine...the clutch in safety switch wire had broken...

    But is sounds like corrosion/chafed / broken wire or heat is causing the resistance to go up, and cause the no start condition
    #20
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