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Discussion Starter #1
Was going to head to work on my bike today and for the first time ever, it would not start.
When i turn the ignition, i can hear the fuel pump kick on for a few seconds. The bike turns over - but just will not start. Pulled the front sparkplug out after turning the bike over for several seconds - and it was bone dry. If the fuel pump IS actually functioning correctly, but the bike is not firing - shouldnt the plug be atleast a little wet?

Any suggestions on how to bench test or run the pump to see that is is actually pushing fuel?
Bike was perfect the night before - but it suddenly will not start. ideas??
 

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Move the tank aside and look down the intake runners while you are cranking. You should see fuel shooting from the injectors. Don't drop anything down there!

That's the easiest way without pulling the pump out. Otherwise you have to yank the pump, submerge it in a bucket with a power source, then run it into another bucket while measuring the volume/time and comparing to spec.
 

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The way I've done it in the past is to plumb a pressure gage into the fuel line loop using quick disconnects. The pressure spec is in the shop manual. This will tell you if the fuel pump and fuel pressure regulator are building pressure, but it won't tell you if the injectors are clogged. Doing it now, I'd probably just pull the output line off the injector connection, put it into a bucket and use the bike to run the pump to make sure there's flow.

If the pump seems good, you might try dripping a few drops of fuel into the intakes and then try to turn it over. It should start briefly. That would then lead you to suspect the injectors. If it doesn't start you could then check to see if you have spark.
 

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If I remember correctly, the fuel pump won't run while turning over if there is no ignition... It will prime when you turn the key but won't run while turning over.

Easy way to check is put your ear on the tank while you crank it, you should hear the pump whirring while the motor is turning over.
 

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You're right, but the fuel pump runs when you turn on the ignition to prime the system. That is enough to get a pressure reading or see if there's fuel being pumped out. Not enough to measure an actual flow rate though.
 

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Spray starter fluid in it. If it cranks and doesnt run, then you have a fuel pump issie. If it doesnt crank you have a spark issue
 

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Discussion Starter #7
Still stuck! PLEASE Advise!

This sux - The bike ran fine when i parked it. then following morning it would not start (turned over just fine but just wouldnt fire)

Question on the 2 relays under the seat. When I turn on the ignition, i can hear/feel one of the relays engage and start the fuel pump. Then other relay does not seem to do any thing when the ignition is turned on....Should it ingage as the other one does? I swapped the relays to see if maybe one was bad but after swapping - still only the one relay activiated when the ignition was turned on.


I pulled the plugs and they both have good spark while turning over.

NOTE: Plugs were replaced about 2 weeks ago with the exact Champion plugs recommended in the bike owners manual. However, when I pulled them out last night the were both completely covered in BLACK carbon. I dipped them in gas and they instantely turned the gas black but cleaned right up (not sure if this is significant)

BTW - I have had the tank off numerous times and finally, last night found an excellant way to remove and test. Just take the bolt out that attaches the 2 fuel lines to the top of the block - this way you have about 12 - 15 inches of fuel line to play with. It was long enough completely remove the tank and place it on a chair next to the bike - while fuel lines and wire remain attached. NOTE: only the 2 fuel lines and the wire are attached - i removed the other 2 hoses and never reconnected them about 6 months ago. I also removed the emissions box/filter they attached to that was next to the battery.

If ANYBODY has any additional ideas/trouble shooting options i would really appreciate your input. Its been 2 days and i cannot get this thing to start.
 

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Well if you have spark, then it's probably a fuel issue... If the fuel pump is priming when you turn the key on, it's probably not electrical. It could be a split hose or disconnected hose in the tank (open the tank and watch for spraying when you turn the key on and the pump primes). It could be a clogged fuel filter. It could be crap in the tank clogging the fuel pump inlet. It could be problems with the fuel line quick disconnects (not connected all the way or problems with the o-rings). It could be something in the fuel lines. Or it could be the injectors - clogged or an electrical problem.

I'd check for a split hose and the quick disconnects first as those are easiest and very common problems.

You should really reconnect the lines on the bottom of the tank before you ride. If you overfill it, you could drain gas onto the top of the cylinder head. On mine I have both lines tee'd together to the drain line going to the bottom of the fairing.
 

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Discussion Starter #9
Its definitely a fuel issue!

Removed the tank and fuel pump - I found no disconnected or cracked hoses in the tank.

When i turn the ignition on - I hear the fuel pump kick on but no fuel is spraying out into the cylinders.

I removed the fuel filter and could blow air thru it with minimal effort. However, i did notice the filter (and the air seperator) were empty

I would say that either
1) the pump is not actually pumping fuel
2) or the inlet is blocked -preventing fuel from reaching the inlet to begin with
3) there is something wrong with 1 of the 2 quick-connect fuel lines that plug into the bottom of the tank/pump. Any idea on how to test to see if the quick connector is functioning and letting gas flow?


The fuel pump was replaced by the previous owner in March 2012...(not sure how relevant that is)

Any other ideas of suggestions you have are greatly appreciated




Stupid Question: where the hell is the inlet? is it the opening below the rubber casing on the actual pump?
Also - this is really stupid but, to make sure i cover all the bases - which way does the fuel flow thru the filter? Should the filter "IN" side be pointed down or pointed up?
 

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The fuel pump has a gauze pre filter below it the pump can be removed from the
aluminium base to get to it.
The filter INLET fits to the fuel line loop coming from the pump top,
if your filter has an arrow on it it should be pointing down to the base
of the flange.

brian.
 
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