Priming Empty Carb Bowl

Joast

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I bought a secondhand(?) bike with a 2 stroke chinese engine. Looks like it has one of the standard carbs. I drained out all the old gas from the tank and replaced the old fuel line and filter. I cant find any prime button on the carburator. The petcock/ fuel valve has 2 settings Run and Off.
The carb has a spring loaded thing on the bottom of the float bowl which looks like a spring loaded drain. I don't think it getting gas into the float bowl. When I pulled the carb bowl it had no gas in it. Do I just keep pedalling this thing in gear with the fuel valve on until it runs or what? I watched videos that had a prime button but I don't see one on mine. My motorcycles have a prime setting on the petcock. Picture below looks like what I have.
Thanks for any help. John
 

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Nickt919

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Start with making sure the tank has fuel. Then disconnect the fuel line from the carb and make sure fuel flows from the tank, through the petcock, and out the end of the fuel line. Once you have that the carb should fill.
If it does not fill once you know fuel is able to flow from the line into the carb then the carb will probably need cleaning. The float, float needle are probably stuck.
The proper way to fix this is to carefully disassemble and clean.
You can try bouncing the bike rear tire up and down to see if that frees it. If it does the fresh fuel will or may wash it clean and it may be fine.
Cleaning the carb thoroughly is the correct way to do it. The tiny holes in the E tube and jet probably are gummed up along with the float needle.

If you do not want to bother with the cleaning process a new carb like that is very reasonably priced. $10.99 shipped on eBay.
 

FrizzleFried

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Push that button on the bottom of the carb/bowl area... That essentially is the screw in the bottom of the bowl you're used to.

If you're not getting fuel out of that port when you push the button... there is a problem somewhere from the tank to the gas port of the carb.
 

DAMIEN1307

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If you do not want to bother with the cleaning process a new carb like that is very reasonably priced. $10.99 shipped on eBay.
That is a JRL BoFeng carburetor which is the same one I run, as well as quite a few others here...I have never seen a reason for the primer on these carby's like the old NT carby's on these bikes have...I have never had to prime the carb to get fuel in it or to start it...Nick already has told you what to do with the carb, clean it or replace it...lol.

You can get it on ebay or you can get buy it for a dollar more at Amazon.

 

Joast

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Thanks all for the help and links to the carbs. I looked at the float and the little fork things that are above the float and they were bouncing up and down freely. The inside of the float bowl/bottom of carb had no gunk or particles or anything that I could see.
So as I understand the comments, the bowl should just fill on its own when the fuel valve is turned to ON unless there is a blockage somewhere. No prime should be necessary. Will try it agian tonight. Thanks Again. John
 

FrizzleFried

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Dunno if I am special, but I've always had much better luck opening the valve in the bottom of the bowl to get the fuel in there. There is, often times, a pressure difference between the line and the bowl... think how slow things come out of your detergent container...until you open a vent. That valve is the "vent".

When you see gas come out... you know you have fuel in there.
 

Joast

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Dunno if I am special, but I've always had much better luck opening the valve in the bottom of the bowl to get the fuel in there. There is, often times, a pressure difference between the line and the bowl... think how slow things come out of your detergent container...until you open a vent. That valve is the "vent".

When you see gas come out... you know you have fuel in there.
That may be the issue. Will give it a try. Thanks John
 

DAMIEN1307

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There is, often times, a pressure difference between the line and the bowl... think how slow things come out of your detergent container...until you open a vent
Keep in mind that with these 2 strokes, gas will be drawn in as the piston pops up and down as you try to start it, sucking the gas from the gas line to the carby, and then the motor...Once the gas is in there from this drawing action of the motor, your bowl will be filled to wherever you set the needle valve for.

Ps...It's just a simplistic explaination, not necessarily a technical explaination..lol.
 

Joast

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Though not mentioned yet, are you using a 100% ethanol-free gas? This has nothing to do with octane levels. Gas with as little as 10% ethanol can in as little as 3 months start causing issues with fuel flow and starting.
Yes I am now, bought it yesterday and mixed to 32/1. The local Moto has Ethanol Free.
Now the guy I bought it from said he used "premix" (didn't know the oil ratio), but he said alot that
was likely BS so I am not ruling out that possibly the carb is gummed up somewhere. Thanks John
 
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