Anybody Have Any Fuel Pump Issues?

Phil Tarman

Phil Tarman

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Location
Greeley, CO
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2010 Silver NT700VA (ABS)
A quote from my ride report on the Wild West 1000:

When I got to the gas station for my finishing receipt, my GPS read 1000.1 mile. My odometer said I'd ridden 1004 miles (plus I'd ridden .7 miles from the Marriot to the gas station). On the .7 mile back here I didn't put my ear plugs in and kept hearing a sound like the beeper on construction equipment for when it backs up. When I got to the parking lot, I realized it was me! I think it's my fuel pump.

I called my dealer on the north side of Denver and reminded them that I plan on leaving next Tuesday for the Three-Flags Classic and they told me to ride the bike up this afternoon and they'd "take a listen" and that if they didn't have the fuel pump in stock, they'd expedite it and get it fixed Monday. Now all I have to worry about is riding it to Sun Honda, back to the Marriot, back to Greeley, and back to Sun Honda. :)

I rode up to Sun Honda this afternoon and the service writer and I went out to listen to my fuel pump noise. When I turned the key, nothing sounded strange. Then when I started the bike...nothing sounded strange. We tried turning it off and starting again and nothing sounded strange.

She went back and talked to the mechanics who've worked on NTs and they both said that they'd had a bike or two come in with owners telling them about the same noise. And when they've checked the bikes, the noise was gone, never to return. Their theory is based on the fact that everyone who's heard this sound had just filled up their tank. They think it must be some vapor in the pump. I don't know what it is, but it's not making the sound now.

I just don't want my fuel pump going out between Loa and Castledale, Utah!

Kat, the service writer, told me that if it acted up again I should call them and they'll overnight the part to Denver and work me into their schedule early Tuesday morning.
 
I believe that our NT is experiencing intermitent fuel pump failure. On one instance, the bike started and idled fine. But under moderate acceleration, it would hesitate. After turning the bike off and back on, the problem went away. No engine light was present.

On the second instance, the bike started and then immediately died. Upon trying to restart the bike, no joy. Turning the bike off and back on, the bike fired right up. Again, no engine light.

These are the same issues I've experienced before with a fuel pump that either doesn't initial come on or runs but at sub-par output. I plan on replacing the unit this winter. I've heard of someone else on this board that had a fuel pump issue (pump was operating below spec volume output).
 
Does it go on and off with the switch or continue to whine like the Connies did when you shut off the switch?
I'd check the fuel pressure first.
 
Mine was more of a beep (like back-up warning devices on trucks and construction equipment). It stopped when I turned off the key.

I always thought of the Connie whine on shutdown as the sound gyros make on a plane when you turn the master power switch to "off."
 
as next in line as miles reported on the NT, I have not had any issues with fuel pump. that is a really funny noise maybe emanating from it. now I know what to expect now that we have a guinea pig. no, really phil hope no issues with it and you can complete ride
 
If the fuel pumps are similar to the ones fitted to the CX500 turbo's in 1982 (I know it has been a long time) then I can understand why they would make such a noise.

The CX500 turbo fuel pumps are basically an outside cylinder that have an inside smaller cylinder spinning within it. The inside cylinder has needle bearings on the outside edge and spins eccentrically forcing liquid (fuel) through the pump at high pressure.

If air entered the pump it could easily cause "beeping" noises as the air is "squelched" when the internal cylinder of the pump spins eccentrically.

I have a picture of the CX500 turbo fuel pump that I can post if anyone is interested
 
Daboo said:
Several have had fuel pump issues on the UK forum, but there's might've been older bikes.

Chris
Click to expand...
yes the 650cc bikes in the uk did have intermittent fuel pump probs. Quite often related to the relay/solenoid which used to stick/fail. When the pump itself failed quite often a sharp "THWACK" with a medium sized spanner "unstuck" it for a while. I think they tended to gum up with all the crap that was in the fuel. Because they were carbed bikes the fuel pump was only really there because the carbs were up under the tank and the lower part of the tank was level with them so there was no head or pressure. So they were only really there to empty the bottom of the tank. A common trick was/is to bypass the pump by pulling off the pipes and joining them. Of course fuel range was then reduced due to not being able to access the bottom of the tank. But if you were riding on a budget it was far cheaper than the price Honda wanted for a pump.
Of course 700's being fuel injected I guess that wouldn't work. However a good "THWACK" might !
 
The electric fuel pump fitted to the 650 model is a low pressure device similar in principle to an SU fuel pump. Its used because the fuel level in the petrol tank can drop below the float chamber level. It pumps all the time but is vital to drawing the reserve fuel from the tank.
Its effectivly a solenoid piston pump that relies on a set of contact breaker style points to interupt the current flow thus allowing the piston to return under spring pressure.
These contact breaker points fail just like contact breaker point in a distributer. They can be replaced as a diy job quite cheaply. Complete new pumps are quite pricy. Alternative design pumps are also fitted.
The same pump is fitted to other Honda bikes that also use carburetors.
A control relay is used to ensure that the pump only runs if the engine is running. Failures of this relay are rare. When the pump fails no amount of wacking will get it going. The pump can easily be by-passed in an emergency and for test. However, only about 150 miles worth of fuel rather than 180+ can be drawn from the tank.
 
bogbody said:
The electric fuel pump fitted to the 650 model is a low pressure device similar in principle to an SU fuel pump. Its used because the fuel level in the petrol tank can drop below the float chamber level. It pumps all the time but is vital to drawing the reserve fuel from the tank.
Its effectivly a solenoid piston pump that relies on a set of contact breaker style points to interupt the current flow thus allowing the piston to return under spring pressure.
These contact breaker points fail just like contact breaker point in a distributer. They can be replaced as a diy job quite cheaply. Complete new pumps are quite pricy. Alternative design pumps are also fitted.
The same pump is fitted to other Honda bikes that also use carburetors.
A control relay is used to ensure that the pump only runs if the engine is running. Failures of this relay are rare. When the pump fails no amount of wacking will get it going. The pump can easily be by-passed in an emergency and for test. However, only about 150 miles worth of fuel rather than 180+ can be drawn from the tank.
Click to expand...

If the pumps fails with the 650, you can keep going, but if the pump fails on the 700, you are dead in the water!

Mike
 
The fuel pump on my NT quit at 1800 miles. The bike would just quit running or would stop and start back up. One time it completely quit and 15 min later it started and ran fine. Got it to the dealer and could NOT find anything wrong. Left the dealer and got 30 miles away and it quit. Two hours later the dealer picked me up and it still would not start. When we arrived at dealers service center, it started just fine. Three days later the service man had the bike running and it quit and as he leaned on it, he heard the pump kick on. End of story, bang the tank and it would either run or quit. New pump installed and no more problems and now I have over 18,000 miles on it.
 
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