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Discussion Starter #21
So, which wire powers the fuel pump, as that seems to be the only thing keeping us from hearing the pump prime.
Solid Brown or brown/black stripe? I'm thinking brown/black stripe.
Brown with black stripe at fuel pump cutoff relay shows no voltage w/ignition off, and 12v when ign on.
Solid Brown at fuel pump cutoff relay shows 12v when ignition is first switched on, then, 2 seconds later it drops to zero as the relay clicks. On the schematic, this solid brown wire is shown to travel also to the instrument cluster.
Let me ask one other question...the noise we're calling a fuel pump priming noise seemed to come from the instrument panel, and not from under the tank...but I could most certainly be mistaken, and have been assuming so.

BTW...as a last resort, the first time the motor failed to start, I did try the throttle at wide open while cranking as its something that on a carbureted engine would clear a flooding condition. Since there continued to be a strong fuel smell I concluded that this WOT process was making the flooding problem worse. When there was a puddle of fuel under the bike, I was certain. Are you absolutely positive the injectors are off at WOT while cranking? I'll try it again if you're certain.
 

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brown/black is the thermistor, it's responsible for turning on the low fuel lamp

solid brown is the power wire.

you are reading the schematic wrong. the brown/black travels to the instrument cluster, the brown is the power feed from the fuel cut relay


you have 12v to the pump. so your pump is probably dicked, or you have an open ground.
 

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Discussion Starter #24
Okay, then. It sure seems to be the culprit, at least for the noise. I'll replace the pump and and remember to use your trick for cranking, Wibbly, when I don't want fuel delivery while checking the ignition (if there is still no spark).
Can't thank you guys enough for your patience and help. Sorry about the misread on the brown wire going two places, it only goes from the pump to the relay.
 

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You can check fuel pump operation at the connector. Open the connector and put your meter (set for DCV) leads across the brown and green wires on the harness side. When you turn the ignition on you should get battery voltage there for a few seconds. If you don’t get voltage at this point check the ground (green) wire continuity and the brown wire continuity back to the fuel cut relay. You have already stated that you can hear the relay pick up so I am assuming that it operates correctly.
You can also take a jumper straight from the battery terminals and connect them to the pump side of the connector (brown and green) momentarily to ensure that the pump works. If you apply voltage directly to the pump leads and it doesn’t run, obviously the pump is bad.
 

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Question for Wibbly as regards the engine flooding. Is it possible that the fuel pressure regulator is also shot? If the pump is not running and the pressure regulator is stuck, will the vacuum from the cranking cylinders pull fuel through the return line and flood the cylinders? Just a theory.
 

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Discussion Starter #28
Hot wired the fuel pump and nothing happened...no noise, no vibration, nada.
Removed tank and removed the fuel pump assembly...what a contraption that thing is:
134914


The rubber boot over the coiled up plastic baffle melted away into a gooey mess presumably from the ethanol in fuel. Its on its way to the test / work bench to figure out what's supposed to be happening with all the tubes, hoses, and canisters. Hopefully, I can get away with just replacing the motor and gasket.
pump.jpg
 

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Yep, and it's a pain in the arse to get in and out, I've had to do it a few times. Good luck, I hope that's the source of your problem.
 

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The only problem is that Honda only sells it as an assembly and it ain’t cheap!! I had the same issue with the’03 that I just finished refurbishing. When I pulled the pump out to de-rust the tank the wire for the fuel level thermistor just fell right off. The pump and filter were looking pretty ragged and the rubber boot had disintegrated. Rather than rolling the dice on that mess I decided to just replace it.
 

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Discussion Starter #31
Received the pump / filter / gasket kit quickly, but still waiting for back ordered preformed 9mm return hose (the old one disintegrated) and the return baffle rubber casing (the old one was a gooey mess).
Pump makes all the right sounds, so things are lookin good.
Will report when repairs complete.
 
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