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1994 RSL, Fuel Pump Failure

pablo

Member
Going down the interstate the other day and my bike just quit. My fuel pump doesn't seem to be working. I don't hear it wind up anymore when I turn the key. What are some things to look at? I've wondered about the relay. How do you test one of those? :scratch
 
In order for the fuel pump to come on (and assuming for a minute that the pump is good), you need the following:

Key on
Kill SW centered,
Sidestand up
Fuse 5 good
Fuse 6 good
Fuel pump relay good
Motronic relay good
Fuel tank electrical connector seated

So I would check the fuses and connector, maybe reseat the relays. Then if no-go,

Does the engine turn over, if yes, the kill and sidestand switches are okay and the relays are most likely getting power.

Then you could swap the Load Relief and Fuel pump relays if reseating them didn't do any good.

You could also try putting a jumper in place of the fuel pump relay to see if the pump comes on, but I don't know which pins off hand.

http://www.mac-pac.org/wp-content/uploads/2011/01/R1100RT_Elec_Diagram.pdf

RB
 
The wind up sound is the ABS, not the fuel pump. Fuel pump is more of a constant hiss.
 
The wind up sound is the ABS, not the fuel pump. Fuel pump is more of a constant hiss.

No, the original poster says it correctly. When all electrical connections are working (sidestand up, kill switch in run position), the fuel pump will cycle on for about 1-2 seconds then shut off - when the key is turned to the run position. ABS winds up only after you start rolling.

If RID is lit up then I would swap fuel pump relay with horn relay. There are four identical relays in the box.
 
Thanks for the suggestions. I took the tank off and removed the fuel pump assembly today. I was hoping I would see something physically wrong but no such luck. I inspected the fuses and they looked and tested fine. I made sure the relays were all fully set in place. I never got to move them. I checked the kill switch to make sure it was centered. Finally I connected the wiring for the full pump. I let the pump assembly rest on the right cylinder. Naturally when I turned the key one position the pump hissed for about 2 seconds like suggested. I tried several times and it did it each time for 2 seconds then quit. So now I'm not sure what was happening or wrong. I suppose I will buy some quick disconnects and reassemble the bike. Then I will see if it starts.
 
That two second run time of the pump when you turn the key is exactly what it is supposed to do. It is pressurizing the fuel rail and will not come on again until the Hall Effect Sensors are actuated by the revolution of the motor by hitting the starter button.

You may have had a bad connection under the tank and after removing and replacing it now it works again. I would inspect the contacts of the connectors and clean them as best you can with contact cleaner. Then put some dialectric grease on them before you plug it back in again to stop surface corrosion.
 
It is normal for FI pumps to become intermittent when they are in the beginning stages of failure. It is very possible that as suggested, there was a loose connection or the vibration of removal jostled the armature enough to allow operation again (at least temporarily). Whacking the tank can sometimes provide a temporary cure when a FI pump fails to run.
 
I'm starting to wonder if you have a bad hall Effect Sensor. Fuel pump failures are pretty rare. HES failures are pretty common, especially on a 20 year old bike.

The fuel pump sounds like it's working now. Put the bike back together and see what happens when you try to start it.
 
That's a good point Jim.

Pablo, when the fuel pump stopped working did you notice any other symptoms?
- Was the RID display still on and working?
- Did your headlight and ignition lights still come on?
- Did the bike still turn over?
 
Happy Wanderer, the answer to all of your questions is "yes". After the bike died, I coasted off the interstate and tried to restart it. Everything seemed normal but the bike would not fire. Due to background noise, it was hard to tell if the pump was working then or not. It definitely was not working when I got home. After I took everything apart NOW it seems to work. I will start reassembly soon and see if the bike will fire up.
 
I'm back on the road! Took the bike for a 50 mile ride this weekend and everything worked fine. Hopefully it was just dirt on the 4 pin connector. I put the contact cleaner to it and seemed to get a lot of dirt out. Dabbed on some dielectric grease and reassembled everything. Thanks everybody for your suggestions. :clap
 
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