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Discussion Starter · #1 ·
Checked fuel pump , replaced fuel lines , Starts when gas is poured into carbs but only till gas is burned out . No fuel getting to carbs ? What do I need to do next . Can't afford to take it in . I have the carbs off and on them bench .
 

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What bike is this? I would check the tank filter/vacuum. If its a vacuum operated fuel valve there should be a vacuum line from a nipple somewhere on the head/barrel/one of the carbs/fuel rail to provide vacuum. To check simply pull off the fuel line and get the motor running with a squirt of fuel. Fuel must flow if not then there is no vacuum or the diaphrqgm inside is toast. Does the pump prime and does it flow fuel....again fuel line off and a ignition on. If the pump filters are clogged then a revers flush may work....even just to the extent of identifying the fault.

Good luck
 

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Discussion Starter · #3 ·
What bike is this? I would check the tank filter/vacuum. If its a vacuum operated fuel valve there should be a vacuum line from a nipple somewhere on the head/barrel/one of the carbs/fuel rail to provide vacuum. To check simply pull off the fuel line and get the motor running with a squirt of fuel. Fuel must flow if not then there is no vacuum or the diaphragm inside is toast. Does the pump prime and does it flow fuel....again fuel line off and a ignition on. If the pump filters are clogged then a revers flush may work....even just to the extent of identifying the fault.

Good luck
I'm not finding any such vacuum line all 4 carbs have diaphragms. I'm not a mechanic so things need to be very simple I'm also an old fart and just trying to get this thing ready to sell . It was running great prior to our summer heat 110 degrees in the shade . put it up with some fuel additive to keep gas from turning to glue . Fuel pump works when running but no throttle to keep it running after gas burns off , No squirt of fuel from carbs .
This is the best I can describe my problem .
 

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Fuel pump works when running but no throttle to keep it running after gas burns off , No squirt of fuel from carbs .
This is the best I can describe my problem .
What exactly are you doing to "test" the fuel pump ?

It sounds a LOT like a clogged fuel filter or that you are getting no power to the pump or the pump has ZERO output even though it is "running".
 

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Discussion Starter · #5 ·
What exactly are you doing to "test" the fuel pump ?

It sounds a LOT like a clogged fuel filter or that you are getting no power to the pump or the pump has ZERO output even though it is "running".
Pump runs and when taken off the input to carbs it shoots gas out . Filter seems OK as the gas does get thru it . Right ?
This thing run good just before I shut it down for summer . I do not ride after it hits 100 degrees . I am currently cleaning carbs ( off the bike ) Pulled jets etc. and sprayed carb cleaner thru all the insides . Just on 2nd carb now .
 

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Discussion Starter · #6 ·
I'm not finding any such vacuum line all 4 carbs have diaphragms. I'm not a mechanic so things need to be very simple I'm also an old fart and just trying to get this thing ready to sell . It was running great prior to our summer heat 110 degrees in the shade . put it up with some fuel additive to keep gas from turning to glue . Fuel pump works when running but no throttle to keep it running after gas burns off , No squirt of fuel from carbs .
This is the best I can describe my problem .
Found vacuum stuff ,
 

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Found vacuum stuff ,
If......there is a fuel pump, there probably is NOT a vacuum operated petcock too; no need for both.

So, hopefully when you get the carbs all back together it will work better.
Might need to run some cleaner through with fresh gas to finish the job though.
 

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Discussion Starter · #8 ·
If......there is a fuel pump, there probably is NOT a vacuum operated petcock too; no need for both.

So, hopefully when you get the carbs all back together it will work better.
Might need to run some cleaner through with fresh gas to finish the job though.
Thanks . Throttle cables driving me crazy today . I had to stop before it accidently caught on fire just as I pushed it out of the garage :mad:
 

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Discussion Starter · #9 ·
Thanks . Throttle cables driving me crazy today . I had to stop before it accidently caught on fire just as I pushed it out of the garage :mad:
Still will not run . I am out of ideas, plus springs keep falling out , so back off and try to find solution to these issues .
 

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Checked fuel pump , replaced fuel lines , Starts when gas is poured into carbs but only till gas is burned out . No fuel getting to carbs ? What do I need to do next . Can't afford to take it in . I have the carbs off and on them bench .
The only suggestion I have on that is try to remove the cap on your gas tank. Sometimes the seal can be too tight and stop the air flow, and the fuel flow.
 
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