fuel pump ??

[vtduc]

MY '92 907ie just had the sprag replaced and the starter brushes too. now it starts and runs fine but does random 'cutouts' where the motor just dies. after a few of these i realized that the fuel pump was not cycling. key off key on and fuel pump cycles and off we go. i don't see any loose wires and i can't get it to do it by jiggling wires. lately it has happened with more frequency and is pretty scary when it cuts out at speed.sometimes it will come back on on it's own but usually i have to key off key on. any ideas where to look or what to do i.e. . relay , pressure sensor, fuel pump ? ? could it be water in the tank or bad fuel filter.
right now the bike is just not reliable to ride.
thanks for any help.

[pencilbeam]

Can't say for certain, but seems logical your fuel pump should always cycle on and stay on. Dirt water or whatever in the filter will affect performance but not shut the pump down. Relay is the wild card. Just don't know.
Sounds like a defective pump, and if you do a search on the threads here some others of greater detective skills than I possess have found alternatives to the amost impossible to find replacement fuel pump. (I saw an 851 sit in a shop for a year waiting for the factory replacement).

[pencilbeam]

Sorry to spread my comments on multiple posts, but I did have an experience where my fuel pump would not come on at all. Assumed it was the pump, but after opening up the computer under the seat I noticed the circuit board had a short in it. (water intrusion--tiny burned place that is possibly repairable) By dumb luck the shop guy helping me happened to have a used one he sold me for $200. 10,000miles later all is well.

[Dino]

Mine was doing the exact same thing....I was told to check the computer connection under the seat.....I then found the 4 wire harness that goes to the fuel pump and I had a short in that wire causing the exact same condition, the fuel pump cut on and off, Now on mine though the fuel guage also dropped to empty when the fuel pump cut out, you just may have a bad fuel pump or a clogged fuel filter causing the pump to overload. With the ignition key on, check that you have 12 volts at the fuel pump by following the wire harness under the right side fairing to under the tank to the fuel pump if you have 12 volts the relay is good, then it kinda points to the pump....Sorry I cant help more.
Dino

[Dino]

see "shorting out help!!!" August 9th or so I received alot of great help there for this problem.
Dino

[chrisjpitt]

It's worth checking the two relays on the electrical panel at the front - one controls power to the whole fuel injection system, the other switches the fuel pump on. If either one of these becomes faulty of intermittent, they will cause the bike to cut out (a problem mine had). The fuel pump will only run as long as the ECU sees the engine is running (crank sensor) - otherwise it will stop the pump after a few seconds (to guard against fire risk in an accident). As mentioned before - check the ECU box connector and the 4-pin plug & cable to the tank (pump & fuel level sender). The pumps are pretty reliable, but a blocked fuel filter will overload the pump and kill it eventually - this expensive problem is avoided by changing the filter regularly. Mine blocked up only a few thousand miles from new (filler & paint dust in the tank). I believe a similar pump is used in the BMW K-series bikes - and at a push, any 12V submersible fuel injection pump would do the job if you could get it to fit. Cheers, Chris.

[persempre907]

Hi,
the 907 fuel pump is a Bosch, part number: 0 580 463 999.
No matter, as Chrisjpitt told, every submersible 12v pump will work.
Ciao

[vtduc]

thanks to all who replied !
chris had it right. it turned out to be a intermittant relay in the front left panel. i pulled the one controlling the fuel pump and cleaned up the internal and external contacts, problem solved, has not happened since. i carry a spare now.