Fuel flow problem

Loop

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May 27, 2020
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So my carb isn’t getting gas, I put a new filter on and new line and I just get a trickle of fuel, however if I disconnect the fuel line it flows like crazy any idea what could cause it?
it runs fine for a bit then you can hear it starving for fuel then it gets a little and is ok for a second or two then starving again.
 
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Loop

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Also when I turn the fuel on you can see some run down the line and half fill the lower part of it below the filter but that’s where it stays until some runs into the carb then it refills to the same level.
 
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Loop

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I will do that today, going to order a second carb as a spare as well, any suggestions for one?
 

Bikeguy Joe

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NT. Go over it closely and set it up with the right jet. Make sure it's clean, and sealed on the manifold with a schmear of silicone. Let it cure overnight before you add fuel.
 
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Loop

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Got the new carb on today, it is much better made, brass slider better fuel inlet I narrowed the fuel flow issue a bit it was either the filter or the petcock that fell apart on me today lol. Got a new one on the way. No moto biking for me this week again. This is why I need a second bike.
 
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EZL

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May 13, 2016
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Also when I turn the fuel on you can see some run down the line and half fill the lower part of it below the filter but that’s where it stays until some runs into the carb then it refills to the same level.
I'd bet the filter screen on the valve is dirty? Unscrew the valve and blow it out with compressed air. I've thrown brandnew
tank valve away since they are cheaply made of potmetal and use a inline hose connected valve.
 

Loop

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I'd bet the filter screen on the valve is dirty? Unscrew the valve and blow it out with compressed air. I've thrown brandnew
tank valve away since they are cheaply made of potmetal and use a inline hose connected valve.
Yeah that valve was garbage, the filter in the tank was clean, when I disconnected the line it flowed fine. I believe it was the new filter.
 
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EZL

Well-Known Member
May 13, 2016
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Yeah that valve was garbage, the filter in the tank was clean, when I disconnected the line it flowed fine. I believe it was the new filter.
Make sure the cap is venting there are some caps that have poor venting and I ran into that on a Briggs lawn tractor years back
and I suppose the tiny vent in the cap got dirty and that was the reason the fella sold the tractor and the mechanic never caught
the original problem with the tractor but also compounded a problem with it by leaving out a engine fan on the flywheel which
caused the the plastic fan to destroy itself. The mechanic must have been working on it and had too many beers and smoking
doobies? :mad:
 

Loop

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I need to check the cap but even with it on, the fuel flowed easily when it wasn’t on that filter.
 
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EZL

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I need to check the cap but even with it on, the fuel flowed easily when it wasn’t on that filter.
You are probably right on the filter since the fuel flowed ok with the cap on or even off. Although, the fuel flow will be slower
flowing when it has a filter to go through. Remember, there is a directional fuel mark (arrow) on the filter and I usually look
for it to be sure the filter is installed correctly. I suppose that could also cause a air-lock on it, just a guess? My little 49cc
doesn't show much flowing through the filter and doesn't show the filter full of fuel. I suppose it's because of the small
carburetor fuel capacity and fuel demand on the engine when it's running.
 
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