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Hello everybody,
I have a CB1100 EX from 2013 and around 10.000 Km with it. For couple of days I have a problem with the fuel pump I think . I'm not really sure about the real nature of the problem and maybe some of you guys have some knowledge about it. It all started when I was parking the motorcycle with the back on a small slope with the engine working but the clutch was engaged. After that, when I tried to start the bike the normal noise of the fuel pump working before starting the motor couldn't be heard anymore and ofcourse the bike did not start. After many attempts to push it and starting it in second gear, finally I managed to start it . When I stop it again, it did not work anymore until I push one or two times really hard on the front fork. Sometimes works normally, but sometimes I have to repeat the procedure from above. Anybody ? Any idea? Could be a improper contact somewhere? Is the fuel pump going to die on me ? Thanks !
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The fuel pump won’t run unless you push hard on the fork a couple of times? Sounds like a bad connection somewhere.
First I’d check the battery/battery connections. The fuel pump connector is behind the left side cover. Make sure it is engaged and not corroded or anything. Then check the main ground under the tank. The fuel pump is connected directly to it. If loose, that would do it.
When the fuel pump doesn’t run, does the starter spin? If not maybe the kill switch is going out.
There is always the possiblity the pump is failing. Lets hope not, but it can be checked pretty easily.
Off to look at the wiring diagram...
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I would check the connection on the battery, loose or corroded first thing to check ,
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After you check Popgun's advice in PP 2 & 3 of post 2, including unplugging and re-plugging the connector and insuring at all the pins/sockets are fully engaged in the connector cavities, then if that does not solve the issue, swap the two relays.
I do not know about the 2013, but the 2014 standard has a 4 pin connector (to accommodate the fuel gauge).
Yellow/red changes to brown at the connector, then goes to the fuel pump relay for power.
Black/white changes to green/black at the connector, then goes to ground.
If the ground is clean, as Popgun already suggested, the pump can be tested by powering the yellow/red wire, while grounding the black/white.
I am sure Popgun will advise if the 2013 schematic is different.
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Could be lots of things as has been said but, I recently had trouble with my kill switch.
Do you use it? Have you tried clicking it back and forth or waggling it from side to side to see if there is a loose connection? If there is it will stop the fuel pump from working.
The contact on mine was poor so I stripped it, cleaned it and re-sat the spring, with a washer behind it, to load it up and make it push a little harder against the contact. Did the trick.
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If it was a fuel pump problem, why would bump starting work? And what would pumping up and down real hard on the forks do for a fuel pump?
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Sharky,
Your problem sounds a lot like what happened to me. Mine turned out to be an intermittent malfunction in the kill switch. One sure way to tell if it's the kill switch is to watch the "check engine" light. When you first turn the key on and don't hear the fuel pump, if the check engine light doesn't come on, you probably have an intermittent kill switch.
Here's my previous post on the subject.
http://cb1100forum.com/forum/showthread....#pid185066
See post #31 for details that will tell you right away if the problem is in the kill switch.
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Ferret, bump starting or pushing the forks up and down cause loose connections to make and unmake. Thats why I suggested checking the grounds. Like flyn I suspect he has a kill switch problem, but being a technician, I tend to do circuit analysis. He says the fuel pump doesn’t run. Its either missing voltage (say a bad kill switch) or missing ground. Should be easy to find, if one can use a DVOM. Tracing the problem is not hard, but has to be done in a logical sequence. As mentioned it could even be the fuel cutoff relay. We’ll get it though.
Doc, the 4th wire on the ‘14s and up is for a thermister input to the meter. ‘13s do not have this and thus only have 3 wires.
The ‘13 wires are different colors than on the ‘14s.
For the 13 the fuel pump harness is Green (ground), Brown (hot) and Green/Black for the sender. Same colors in the bike harness.
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Sharky the red engine-stop switch feeds from the 10a start fuse and then to the engine start button.
if the engine stop switch is not working the start button does not work ( engine starter makes no attempt to start ).
So if you can spin the engine your engine-stop switch is working. ( according to the diagram )
The "fuel stop" relay is controlled by the engine control module, if the fuel pump is not making it's usual sound when the meters cycle it is worth checking or swapping the relay's (the two similar fuel-stop and starter relay's ) in the fusebox under the seat initially.
to hear a relay click ( when the meters cycle ) ( means the ecm controls the fuel on ) is a good start but it does not mean the contacts are working.
And flynrider's suggestion of the ecm light is a great tip!
Hope that makes sense.max
