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No fuel to fuel rail?
- Thread starter eastbay
- Start date
GTRider
52184
Is the pump outputting pressure through the filter? If not, double-check the wiring connections to the pump to verify they are not reversed.
If you are getting fuel delivered to the rail connection but none at the rail itself then yes, it’s possible the regulator or rail has collected a load of debris or dissolved rubber spooge and is blocked. Brick-k bikes that are allowed to sit long-term with fuel in the tank tend to have the rubber mount bits dissolve into a viscous spooge that is destructive to pumps, filters, regulators, and injectors. But usually the pump and filter fail before the spooge can reach the regulator and rail.
Best,
DeVern
If you are getting fuel delivered to the rail connection but none at the rail itself then yes, it’s possible the regulator or rail has collected a load of debris or dissolved rubber spooge and is blocked. Brick-k bikes that are allowed to sit long-term with fuel in the tank tend to have the rubber mount bits dissolve into a viscous spooge that is destructive to pumps, filters, regulators, and injectors. But usually the pump and filter fail before the spooge can reach the regulator and rail.
Best,
DeVern
Yes, it is possible. Though When I blow through the front hose
I can feel air come out at the top of tank, where it is supposed to. I get fuel out of the rear tank metal but the hose then goes in toward the engine , I assume to the regulator, but does not get to the rail where it comes out into the rear of rail. Isn’t.the front line the return?
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You are correct. I was thinking the fuel came in at the rear of rail, but It’s going out to the regulator from the rear. Then from regulator to tank return. I think the line to or from regulator is blocked. Will investigate tomorrow, thanks.
If either line to or from the regulator was blocked, you would have way TOO MUCH FUEL in the fuel rail.
The pump fills the rail (at too much pressure). The regulator bleeds off the excess pressure and returns it through the forward hose back to the tank.
You do realize that the pump only runs while you are pressing the starter button (and after the engine has started) right?
The hose that comes out from behind the radiator is the excess pressure return from the regulator. It connects to the forward nipple on the tank.
The hose that disappears between the throttle bodies and the coils is the input to the regulator. It connects to the rear of the fuel rail.
The hose that comes from the rearward nipple on the tank is the fuel pump outlet (by way of the filter). It connects to the front of the fuel rail.
Are all the hoses connected correctly?
If so, open the gas cap. Remove the cap assembly if you still have silver flapper valve in the cap assembly so you can see and hear what is going on.
Turn key on, turn kill switch to run position, put the bike in neutral, and push the start button.
Do you hear the pump running? Or do you hear it continue to run for a second or two after you let off the button?
No? You have an electrical issue or a bad pump.
Yes? Remove the short hose on the end of the filter from the tube inside the tank. Hold it pointed inside the tank and run the pump. Observe the flow. Poor flow would indicate plugged filter, filter installed with flow arrow pointing toward the pump instead of pointing away (correct way), or a bad pump.
Also a split filter or a hose in the tank that has popped off would account for the pump running but no fuel at the rail.
Let us know what you find and we’ll go from there.
The pump fills the rail (at too much pressure). The regulator bleeds off the excess pressure and returns it through the forward hose back to the tank.
You do realize that the pump only runs while you are pressing the starter button (and after the engine has started) right?
The hose that comes out from behind the radiator is the excess pressure return from the regulator. It connects to the forward nipple on the tank.
The hose that disappears between the throttle bodies and the coils is the input to the regulator. It connects to the rear of the fuel rail.
The hose that comes from the rearward nipple on the tank is the fuel pump outlet (by way of the filter). It connects to the front of the fuel rail.
Are all the hoses connected correctly?
If so, open the gas cap. Remove the cap assembly if you still have silver flapper valve in the cap assembly so you can see and hear what is going on.
Turn key on, turn kill switch to run position, put the bike in neutral, and push the start button.
Do you hear the pump running? Or do you hear it continue to run for a second or two after you let off the button?
No? You have an electrical issue or a bad pump.
Yes? Remove the short hose on the end of the filter from the tube inside the tank. Hold it pointed inside the tank and run the pump. Observe the flow. Poor flow would indicate plugged filter, filter installed with flow arrow pointing toward the pump instead of pointing away (correct way), or a bad pump.
Also a split filter or a hose in the tank that has popped off would account for the pump running but no fuel at the rail.
Let us know what you find and we’ll go from there.
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Fuel is flowing into and out of the rail and back to tank. No
, getting spark but spark plug dry. Going to pull rail and see if injectors are spraying. I don’t think they are.
To see if the injectors are getting the proper signal from the computer without running the risk of damaging the computer:
https://www.harborfreight.com/search?q=noid+light+tester
Or
https://www.amazon.com/Performance-...93011&rnid=386419011&s=automotive&sr=1-2&th=1
Find the light in the set that best fits the connector on the injector. Plug it in one at a time to each injector lead and crank the bike. It should flash corresponding to the pulses to the injector from the computer. If not, you have a wiring issue or a bad computer. Repeat for each cylinder.
https://www.harborfreight.com/search?q=noid+light+tester
Or
https://www.amazon.com/Performance-...93011&rnid=386419011&s=automotive&sr=1-2&th=1
Find the light in the set that best fits the connector on the injector. Plug it in one at a time to each injector lead and crank the bike. It should flash corresponding to the pulses to the injector from the computer. If not, you have a wiring issue or a bad computer. Repeat for each cylinder.
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The injectors didn’t want to come out. They are really dirty. In the holes they go into are full of crud. I’m trying to figure the best way to clean them out without getting stuff into the opening. Maybe some kind of rubber plug and then flushing it. I’ve heard you can send the injectors off to get them cleaned or some people do it themselves. or buy upgraded ones.
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If they are still in the cylinder head, just use compressed air to remove the crud.
If the injectors are out of the head, remove the injectors from the rail and lightly put them into the holes or if you can find some proper sized plugs (Caplugs) or corks. Use a vacuum first, then brush while holding the vacuum hose as close as possible. https://www.amazon.com/s?k=caplugs&...337536&tag=googhydr-20&ref=pd_sl_2o6f8suu7z_e
Mr. Injector in Idaho will rebuild and test your injectors or can supply replacements for a very good price.
https://www.mrinjector.us/ Quick turnaround.
You will want to replace all 6 ( top and bottom) O-rings before you replace the injectors. Mr. Injector can provide them.
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