[Joezx11]

Gentlemen, I have a 92 zx11c that always runs well until now. Yesterday I road about 50 miles and it was running great. Low fuel lights came on and I put 2 gallons of Sunoco premium ($6.00 gal!!..)within 10 miles my bike started to run like [email protected] It felt as if it was running g out of fuel and would stall out regardless of rpm every 30 seconds as if it was on a timer. I was convinced that I got contaminated fuel but after nursing it home I took a fuel sample and it looks fine. One issue I thi k may be key is the engi e would only start by using the starter as opposed to bump starting as I was still coasting. I remember er reading here that the fuel pump works when the starter is engaged but it
must also sense low line pressure? I'm this king pump or perhaps a relay causi g the
pump to operate only when the starter is engaged?
Any help would be greatly appreciated..
Joe

 

[Joezx11]

So I just removed the tank and ran the engine until the bowls went dry. I can confirm that the pump works only during cranking. Is there a relay to operate the pump while runni g or is that i corporated i to the pump itself?

 

[Claude]

There's a fuel pump relay on the wiring diagram so it is not incorporated in the pump.
Don't you have a manual and wiring diagram?

 

[Joezx11]

Hi Claude,
Thanks for responding. I'm working with a Clymer manual and am not proficient with wiring. I see 3 relays . One is labeled fuel pump relay, p/n 27002-1065..there is another labeled fuel sensor relay p/n 27002-1072 and a third to operate the low fuel light. I was wondering if the fuel sensor relay is the one that tells the pump to operate after cranking or in general what triggers the pump to maintain the fuel supply after the starter button is released? Is this a function that is integral to the pump or could it be performed by the fuel pump relay or fuel sensor relay?
Thanks again
Joe

 

[Claude]

Can't answer your questions; I was just answering if there's a fuel pump relay or not.
Usually, when I had similar problem, I was using wiring diagram and logic and trying to find if there is or not 12V power where it supposed to be some.
My guess about the fuel pump is that it will start pumping when the pressure is lower than a defined level. Check if there is 12v power to the relay and then, to the pump.That's how I would do it if I had to. I sold my C model in 2009 so it is far behind me...

 

[Lennyloo2]

So I just removed the tank and ran the engine until the bowls went dry. I can confirm that the pump works only during cranking. Is there a relay to operate the pump while runni g or is that i corporated i to the pump itself?

Hi joezx11, did you solve this problem as I have a gpz1100 unitrak that has stood since 2013 and pump had seized so I bought another pump and the problem is the same the pump buzzes only when start button pushed

 

[Joezx11]

No, not yet. I have replaced the fuel pump relay and no change. Look I g at my Clymer wiring diagram I see the pump relay gets an input from one coil and the tach..maybe that's what sends the pulse to the relay after cranking?
Electrical is not my strong point so I'm still searching.
If anyone knows what triggers the relay to pulse the pump during running it would be helpful.
Thanks

 

[92Ninjas]

No, not yet. I have replaced the fuel pump relay and no change. Look I g at my Clymer wiring diagram I see the pump relay gets an input from one coil and the tach..maybe that's what sends the pulse to the relay after cranking?
Electrical is not my strong point so I'm still searching.
If anyone knows what triggers the relay to pulse the pump during running it would be helpful.
Thanks

Fuel pump relay should be under the seat somewhere. Find it and start jump the connectors with a paperclip while bike is key on engine off. When jump the correct contacts on the harness plug for the relay, the pump should come on.

 

[Joezx11]

So are you saying that there is always 12v to the pump and the pump operates based on line pressure or does the relay tell the pump when to maintat pressure?

 

[92Ninjas]

So are you saying that there is always 12v to the pump and the pump operates based on line pressure or does the relay tell the pump when to maintat pressure?

The relay receives a signal from one of the coils. Relay clicks on for that signal, pump actuates.

 

[Joezx11]

The relay receives a signal from one of the coils. Relay clicks on for that signal, pump actuates.

Thank you!
I saw that in the wiring diagram. It also goes to the tach but I wasn’t sure. Thanks

 

[Joezx11]

So I removed 2 pins from the pump relay connector plug to inspect
Red wire was hangi g on by a thread. Re soldered the red wire and all is good.the pump pulsi ng increases with rpm now clearly getting that input from the coil as you stated.
Hope this thread can help someone I the future.
Thanks 92ninjas