Fuel not flowing to carbs from tank

[wottdogg]

hi guys and girls,
my 89 zxr250a is having issues with feeding itself fuel. I have taken my tank and airbox off and managed to get it started by manually filling the carbs with petrol but then i put the tank back on it dies due to no fuel. Theres ni blockage in the lines because i can fill the lines with fuel and manually blow it throu and it goes in No probs.
cheers people!!!

[unstuck]

Petcock, or fuel tap if you don't know what a petcock is. Pull it out and give it a clean.
I am assuming there is no fuel pump?

[kiwi-on-wheels]

Check the vacuum hose to the back of the petcock, and check filters /strainers too

[wottdogg]

Petcock, or fuel tap if you don't know what a petcock is. Pull it out and give it a clean.
I am assuming there is no fuel pump?

Hey mate, yeah i have cleaned all that. it flows out as notmal but it dosent seem to enter the carbs. i was thinking maby a pump aswell but i havnt yet found one and im unsure if there even is one?? Cheers.

[wottdogg]

Check the vacuum hose to the back of the petcock, and check filters /strainers too

Hey mate, yeah i have checked the hoses n what not it seems fine. flows out as notmal but it dosent seem to enter the carbs. Its like theres nothing pulling the fuel its just dripping. Maby it is a vaccuume thing n i need to chech again. Cheers.

[Big Dog]

If you disconnect the hose from the carb does it run through?
If not: If you open the fuel flap does it run now?


Stupid phone / Tapatalk, apologies in advance.

[Big Dog]

The only time I have had this issue it turned out the breather hose was obstructed. Mech who did the service 20 kms before hand had pinched it fitting the tank.


Stupid phone / Tapatalk, apologies in advance.

[unstuck]

Hey mate, yeah i have checked the hoses n what not it seems fine. flows out as notmal but it dosent seem to enter the carbs. Its like theres nothing pulling the fuel its just dripping. Maby it is a vaccuume thing n i need to chech again. Cheers.

Is there a strainer under the needle valve? If so it could be blocked if the fuel runs out of the fuel lines ok when disconnected from the carb.

[wottdogg]

Can anyome tell me where the vacuume hose goes to. It shout go from the cock to where exactly?

[unstuck]

Can anyome tell me where the vacuume hose goes to. It shout go from the cock to where exactly?

I would think it would go to a port on the carby.

[FJRider]

Hey mate, yeah i have checked the hoses n what not it seems fine. flows out as notmal but it dosent seem to enter the carbs. Its like theres nothing pulling the fuel its just dripping. Maby it is a vaccuume thing n i need to chech again. Cheers.

1: Disconnect the fuel line from the carb.

2: Disconnect the vacuum line from the carb.

3: Suck on the vacuum line and fuel SHOULD flow from the tank.

4: If NO fuel flows ... put FUEL into the tank.

5: Repeat 3.

[FJRider]

Can anyome tell me where the vacuume hose goes to. It shout go from the cock to where exactly?

The cock owns the bike ...

[wottdogg]

Thanks for the help people got it in the end. Thanks alot.

[unstuck]

Thanks for the help people got it in the end. Thanks alot.

Well what was it? Be helpful for others perhaps to maybe tell what fixed it.

[wottdogg]

It was a leaking vacuume line at the tank end and also, up by the carbs where it has a T join and goes into 2 different lines, one of them wasnt connected properly causing weak vacuume pressure and no fuel making it to the carbs. cheers for the help once again. Hope someone can benefit from this post.