Fuel pump not priming

[Wheaton Jr.]

Hello all,

I finally have a consistent work schedule that will allow me to get to riding more, but recently got a no start issue. I have Wheaties old 2004 with about 96,000 on it, so being he's touched it is probably the problem , but I want to try and get this resolved as warmer weather is upon us.

We took a short day ride a few weeks ago and the bike ran great, no issues. After being in the garage since then, I went to start it, and it would crank and crank, but nothing. It usually starts right up. The battery was somewhat old and after the clear flood start procedure didn't work, I installed a new battery (fully charged) to see if that would do it. It did not. I realized yesterday I'm not hearing the fuel pump prime when I turn the key on, so there lays my issue.

I ran through some of the quick diagnostic tests and these are the results. The lean angle switch, sidestand, and neutral switch are all working correctly. I can hear/feel the fuel injection system relay actuate when commanded as well as the fuel system voltage showing 12.4 volts, but no priming noise as it says it should do. The fault codes it has is 11(no normal signals from the cylinder identification sensor) and 21(an open or short in coolant temperature sensor), but both of those say it wouldn't cause a no start/run scenario in the manual.

Are there any other logical troubleshooting steps to try or any other ideas as it doesn't appear as the fuel pump is a super common failure with this bike, although I'm not ruling anything out. Any and all help is appreciated.

-Wheaton Jr.

[Road Runner]

Try checking for bad connections at the main harness under the tank. I have heard of the Gen 1's there's several white harness plugs under the tank that can get corroded or dirty. Pull them apart and make sure they're clean, and while you're there put some Dielectric grease in them.

[pmk6v]

Also check the ignition switch, My 04 did the same thing and I found a bad connection in the switch. Hope this helps.

[raYzerman]

There have been a few Gen1 fuel pump replacements, not a lot but mostly they get crudded up with rust from the tank.... any issue there?

In addition to the above, there is a multi-way connector near the steering head forward of the engine... the one Road Runner is referring to. Yes ignition switches were an issue. I've read of some disassembling, cleaning up the contacts... there was a recall way back '06 and prior. Also check the starter relay for corrosion in that connector.

Gen 1 also has a Fuel Injection relay.... check Backup fuse is OK, controls clock and odometer, and feeds that relay.

First thing to do is unplug the fuel pump, the R/L (red/light blue) wire is power to the pump. Black is ground. When you go through your ignition cycle, you should be getting 12V there for two seconds when you first turn the ignition on (or kill switch cycled on when ignition is on). If that happens, your upstream stuff is OK. Wiggle ignition switch to see if intermittent, but tough when the ECU shuts it off after 2 seconds.

If you have to do surgery (remove pump), there are some threads we can dig up.
Next question, can one replace just the pump with a generic (as one can do with some bikes). OEM complete with housing is kinda spendy.

[Wheaton Jr.]

So far I have checked the white connectors under the tank. They looked clean and not corroded. Put some dielectric grease on them anyways. The fuel pump is getting the 12V when the ignition gets turned on testing that connector. The tank to me looks like it has rust coating the bottom of it. I have a picture in the link below if it works to confirm how bad it is. From looking at the wiring diagrams, am I mistaken in the belief that if the fuel pump is getting the 12V with the ignition on, it should prime just from that? And since it is not, it points to the pump? Or is there something else that could block that from happening.

https://linksharing.samsungcloud.com/8JuUNTHtf0i7

[raYzerman]

If you're getting 12V there, everything upstream is working, I'd check aforementioned connectors for corrosion anyway, the bike is aging.
But yes, next you need to pull the pump, and check it out. Clean the screen filter, not sure you can backflush. Could be grit in the pump gears jamming it.
Some found connector terminals on the pump may be loose. You're only going to know with the pump in front of you.
Off to dig up some pump threads.......

[FJRoss]

Did you check the plugs to see if they are wet? (Does the pump go through the prime sequence if already pressurized??)
A no -start due to flooding can be a bitch to clear sometimes.
If there is rust in the tank, you could also have plugged injectors... (in addition to a plugged pump screen).

Seems to me I read somewhere that someone was able to get a "kit" to replace pump motor without having to replace the entire assembly. I may be mis-remembering.

Good luck!

[Wheaton Jr.]

From my memory and what I have been told, this bike primes the pump even if already pressurized. I work long shifts the next 7 days, so I'll work on pulling the pump after that time and see what I can find. I have found a thread on a different forum on the trick to getting the pump out. We'll see how hard it is. I haven't checked plugs or anything yet. Thanks for the replies. I'll give an update when I have anything further.

[Cav47]

I have no valuable info regarding fuel pumps, but rather want to say welcome and hello. Your pops is a good dude. Good luck with the issue.

[raYzerman]

One more test you can do before you take the tank apart...... If you carefully can connect a 12V wire to the terminal the bikes red/light blue goes to, and a ground wire to the other, you can test run the pump with a battery for a few seconds to see if it will spin. You can do this later on, after you have the pump out as well.

Not having luck finding the thread I was looking for.... may stumble on it one day. Meanwhile, just for interests sake......

This is Gen2, and I don't know of anyone who has replaced just the pump portion, as implied in the second link. I have never had an FJR pump apart...

http://www.fjriders.com/forums/viewtopi ... mp#p137004
https://www.ebay.com/itm/Quantum-Fuel-P ... SwZAldZYiU

Gen1 has an o-ring that can leak......
https://www.fjrowners.com/threads/gen1- ... st-1197243

Can have wiring or terminal issues.... just be careful.
https://www.fjrowners.com/threads/fuel- ... st-1303230

Yer old man sucks, he keeps telling me the roads down there are flat straight and boring, and not to bother coming down.

[1911]

WOW! Wheaton JR is on the forum. I've got to start paying closer attention. He should have joined up BEFORE some shyster dumped a clapped out old Gen 1 on him. We would have told him to steer way clear of the dude from Chicago with no respect for double yellow lines.

Do Gen 1 and 2 fuel tanks have the same hose and electrical connectors by any chance?

I'd sure like to get my hands on a Gen 1 FSM and Junior's bike.

[raYzerman]

There are several differences between Gen1's and later. Not wired the same.
Gen1 had a fuel pressure regulator on the end of the fuel rail and a return hose. With Gen2, the FPR was incorporated into the fuel pump and the return hose eliminated. Thus a Gen1 tank is different than a Gen2 tank.
The electrical connectors were the same, one for the pump, one for the fuel level sensor. Gen1 has a fuel injection relay, later do not. Fuses at the starter relay on Gen1 is for FI, and later years that is for ABS.... different wiring scheme.
All do the same thing to ultimately power the fuel pump.
I'd bet the Gen1 would run fine with your Gen2 tank, provided you removed the return line and blocked off the FPR on the end of the fuel rail.

[wheatonFJR]

Well, as you can tell, David has a lot more goin on upstairs than his dad. Thanks for helping him out...he's a determined auto fixer so it looks like the 2004 Indiana bike I took out to BC and Kali needs some attention. We rode here a couple weeks ago and no symptoms then.

[raYzerman]

Tidbit.... the fuel pump is most likely two small gears meshing to create pressure. All it takes is something hard and maybe bit bigger than sand to jam in there. Motor is brushless thing, likely not a lot of torque. Do not know if one can tear this down (remove gear chamber cap) or if one can replace just the pump..... never had to get into an FJR pump.....
Give it a few taps and see if it will run once you get it apart... reverse flush? Soak the pickup screen in vinegar to clean up the rust, even the tank.
Look for aftermarket screens, tank rinsing stuff.... Evaporust, if not too bad.
New OEM pump is megadollars.

I replaced a Honda pump that was jammed, tank had a bit of rust, I thought no biggie. New pump jammed temporarily later. Tested old pump on the bench later, it ran fine. I chalked it up to small crud jamming the gears.

[Hppants]

Ray - if he hears the pump motor running when he turns on the key, would that be sufficient data to presume the pump is running? If the pump was jammed with something, knowing the motor is not overpowering, wouldn't the motor not run, or at minimum, run with weird straining noises?

[El Toro Joe]

Ray - if he hears the pump motor running when he turns on the key, would that be sufficient data to presume the pump is running? If the pump was jammed with something, knowing the motor is not overpowering, wouldn't the motor not run, or at minimum, run with weird straining noises?

hey...what are you some kind of trouble maker, or what?

[wheatonFJR]

Ray - if he hears the pump motor running when he turns on the key, would that be sufficient data to presume the pump is running? If the pump was jammed with something, knowing the motor is not overpowering, wouldn't the motor not run, or at minimum, run with weird straining noises?

From what I was told, he was not hearing anything, nothing, naughta…

I know he told me that when he turns the key on, the dials sweep, but was not hearing the telltale sound every FJR rider hears of the fuel pump doing it’s thing.

[raYzerman]

Yep, the key here is to see if the fuel pump itself is gonna work or not work....... seems the power is getting there. Let's see what Junior finds and go from there.

[rbentnail]

I'm going to ask a really stupid question- is the kill switch on? On the Gen2 with the KILL engaged, the dials will sweep but the pump doesn't run. Again, maybe stupid but I'm assuming the Gen1 is the same.

[wheatonFJR]

I'm going to ask a really stupid question- is the kill switch on? On the Gen2 with the KILL engaged, the dials will sweep but the pump doesn't run. Again, maybe stupid but I'm assuming the Gen1 is the same.

Yeah, I want to hear this answer!

Hey, you have to knock out every possibility.