Fuel Problem ???

[9will79]

Hi guys, i'm new here and need help!

Does anyone know how much fuel supply I need for an 02 busa?

I have close to 200 cc/min at around 40 psi. The maximum the pump makes is 48 when dead headed. The fuel flow slows to a trickle when choked in to 45+ psi. With no pressure the pump will flow 1 litre/min.

Bike runs very strong until 8000 RPM's +/- in any gear and just seems to not make more power by that point.

Problem started in the spring when I found the strainer plugged up with rust now that problem is clear.

Not sure where to turn next other than to bring to the dealer and have them replace parts.

Could I be missing some other kind of problem that I have no clue about?

I really appreciate any assistance!
(maybe it doesn't matter but mod's are small...remapped, air filter, D&D exhaust, TRE...ran fine last year 9.82s best)

 

[lil charlie]

I can't help you but..... to the org. Im sure someone will chime in soon.

 

[Lucid]

If you've torn apart your pump and tank and cleaned it, that'd be my first guess. Second is that it doesn't sound like fuel pump anymore, it sounds like maybe an ECU/tuning issue. Turn the PSI up and try it out, but remember that altering things just a little can throw off your tune. I'd ditch the TRE and get it remapped, maybe the tuner will find something either in the hardware or software. Sounds odd.

I'm sure you've checked the basics: plugs, checked/cleaned the injectors, and made 100% certain there are no kinks in the fuel lines.

 

[dadofthree]

to the oRg. Make sure the source of that rust is clear. Maybe tear it apart again and see if you have more rust. Pump could be gone. I'm away from manuals but is there another filter ?

 

[9will79]

Well thanks guys, I'll update as best I can... I'm not aware how to adjust fuel pressure while the pump is installed in the bike. As far I know it must regulate in the tank but i'm not sure what tells the pump to run. When I had it out (filters still on) then I installed a valve and pressure gauge and put the pump assembly in a bucket of clean gas, then did my pressure/flow tests. While its on the bike I am not sure the best way to check pressure while on full throttle?? Surley that would tell me a lot ...
Since there was over 1 litre/min on zero pressure I assume the filters are clean, which they are. Suction and discharge on pump and injector screens are the only ones I know of.
Regarding the ECU... is there any way a y dead battery could affect it? (just replaced)
All my mod's were done 5 years ago and this is the first issue I've ever had.
Does anyone know the best way to check a fuel injector? I live in a small town and don't know of a dyno tester/tuner guy. Not sure what else to say but i really don't want to have to buy a $900 pump. Thanks for helping so far!

 

[Lucid]

You can replace the pump and regulator with badass aftermarket stuff for around $250 shipped, then buy the lines. Check my past threads, though I use a 99 pump so I have a return line (meaning you'll use a different regulator and I think will have to use a fuel rail tap)

But to your point on the battery: DEFINITELY. It's insane how much the battery controls on these bikes. If you just replaced one, hopefully it's good, but your charging system might be out (stator and/or regulator rectifier) Look up ways to test your battery on this site. Your electronics control how much fuel the injectors spray. If you have a weak battery, the injectors might not be getting the correct power, potentially causing your problems. I am no mechanic, as any mechanic can tell by how I explained it, but these were issues I've had with my bikes and stuff that I remember mechanics and other people have told me, so take the info for what it's worth.

First thing I'd do is test your battery and charging system, or grab a battery from a buddy and try it. (for one ride, you don't want to ruin his battery if your charging system is bad)

 

[9will79]

So do I have to buy a replacement pump or do you always have to buy the entire assembly?

Anyone know where to get good prices on them?!!

 

[dadofthree]

Shoot dk55belair a PM. he just worked on his fuel pump in April and i think replaced it in May. You can also do a search using advanced search on this issue.

 

[Lucid]

So do I have to buy a replacement pump or do you always have to buy the entire assembly?

Anyone know where to get good prices on them?!!

You have to buy a fuel pressure regulator to use with your aftermarket pump. The stock one can't be adjusted.

You can try a used stock pump and/or regulator from ebay first if you don't wanna mess with the aftermarket setup.