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CBR250R(J) Fuel pump dramas

Discussion in 'Technical and Troubleshooting Torque' started by escuro, Jul 29, 2008.

  1. Hey guys,

    Problem I've been having for a while now. I actually managed to run it fine without a fuel pump for a good 3 months or so, but decided that ideally, if it comes with one, then it has to be of some benefit (did notice a slight power loss after removing it).

    Anyway, after playing around with it and getting a new fuel cut relay, it worked fine...for a while anyway. Turns out if i give it a good run on a freeway or anywhere giving it some go, it starts to sputter after a while and sounds like its beginning to starve, and eventually, it stalls. Now once this actually happens, I can't get it to go because the fuel pump only works when its started up. I have to actually short circuit the pump relay to get enough petrol in there to start her up.

    So I guess it sounds like the pump isn't actually keeping up with the fuel requirements...does it sound like i need a new pump? Also, I notice that sometimes when this happens and i remove the tank, there is a slight crimp in the tank to filter/strainer line, would this have any impact on the rate of fuel flow? should the pump be sucking the fuel out of there anyway or does it only pump once the fuel is in there.

    any feedback appreciated,
  2. Have you replace the filter ...It sounds like you have more than one problem ..Relay ,pump,and blockage( kink) ..Is it blowing fuses and is it an original fuel pump...
    The kink is worth fixing just to remove a possible problem, and can you test the pump and relay separatly ...An inline fuel pump from auto barn etc will work (around the $70 mark) I seen them used a lot on cbr 250's as for the relay if you have to jump the pump to get it to work again is this strait away or do you have to wait for it to cool down ..
  3. the relay is fine, works without problem

    only problem really is the fuel pump, or perhaps somewhere along the line the fuel isn't flowing

    If there was a kink before the inlet though, would the pump still try to suck the fuel in? or does it only pump once the fuel has made its way in there due to gravity or whatever.

    looks like its a mitsubishi pump, and ive heard before that the cbr250s use these originally...or am i completely mistaken?

    what i meant traviss was that, once its actually completely starved of petrol, the only way to get more in is to start it up(which gets the pump working) but since it has no petrol in it, it wont start...and hence the pump wont run, so i have to short the relay to get it to pump. But i think there was a bit of a kink in the line so even with the relay shorted, the pump sounded like it was running dry and took ages to slow down again(fill)...so i'm guessing either the pump is weak and needs replacing, or its just a blockage somewhere?

    i suppose i'll look into it more when i have some time off. but out of curiosity, any inline fuel pump will work? any specifics like psi before it cuts out etc?

  4. Ok the pump is staved of fuel on the tank side most likely the kink in the fuel line, has it got a fuel filter before the pump if it doesnt cut the line about 2cm either side of the kink and fit a filter ..if it has you might have to get a new bit of fuel line ..Also the fuel tap might have a blockage in it as well (loose rust scale ) which is common .. the Mitsubishi pump was used as original equipment in a lot of models..
  5. hmm, thanks trav...might have to get the tap cleaned etc...or even fixed as its currently non operational...probably also change the fuel line and hopefully it fixes things.

  6. I think you just found part of the problem ..If the tap is stuck theres something in it or its rust ...
  7. nah its actually stuck to the on position, it can't be switched off, or to reserve.
  8. If its stuck on then Something is making it stick ,This could be a build up of rust or foreign matter in the tap and could be causing some of the fuel flow problems ..Taps don't stop turning unless there damaged (bent) or have rusted due to water in the fuel ,I would give it a check while you have the tank off fixing the fuel line its not hard Just take most of the fuel out and undo the tap the seal may need replacing (cheap) and Sumoto have them in stock but if you don't have it apart to long they should seal again ..Or while you have the tank off blow some air back throw the tank just to make sure..
    Also try and fill your tank up before you ride it home it might have enough pressure to get past the kink and get you home ..And a laundry peg or light clip put on the kink to squash it back into shape could help get you home to..