i pulled the carb drain screw and it started then died

Chainlube

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ok it ran, which is progress, so its the gas cap, but now i have either a low bogg at low rpms? do you know what causes that?
Can you post a picture of the bottom of your gas cap and carb please? Low rpm bog can be as simple as the wrong plug, but most likely too rich.
 

motoredjosh

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I would also ask, where exactly do you have the C clip on the needle valve of the carburetor ???

If your running a stock NT or BoFeng carby that comes with the 2 stroke motor kits, it should be in the middle notch/groove of the needle valve at your altitude of 617 ft above sea level.

If that still proves to be too rich, then go upwards on the needle valve to the next to the top notch/groove to lean it out a little more if necessary...There should be 5 notches/grooves on your needle valve...DAMIEN
ok i only have four grooves on my needle it was on the second from top now its on the third from top,
one lower than it was previously so it should be more richer?
i also slightly adjusted the float valve to engage later
it always starts briefly then dies after i drain the carb bowl?
took it out for a run this evening and it started briefly then died
 

motoredjosh

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Can you post a picture of the bottom of your gas cap and carb please? Low rpm bog can be as simple as the wrong plug, but most likely too rich.
it did start the other day after i took the gas cap off but now its not responding,
it usually seems to sputter and stop after i drain the carb bowl? any idea? i also adjusted the needle and float valve today, should i adjust it more?
 

Chainlube

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im running about 35 to 1 of stihl high performance 2 cycle engine oil
That is the wrong kind of rich, that mix is fine. The rich I'm talking about is the air/fuel ratio (AFR), that is there is too much fuel and not enough air the engine will bog down. Start with the clip on the metering needle in the middle, then work up until the mix is right.
Inside the gas cap there is a ridge under the seal, in the side of that ridge, close to the top of the cap there should be a hole to let air into the tank as the fuel runs out to the carb.
 

motoredjosh

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That is the wrong kind of rich, that mix is fine. The rich I'm talking about is the air/fuel ratio (AFR), that is there is too much fuel and not enough air the engine will bog down. Start with the clip on the metering needle in the middle, then work up until the mix is right.
Inside the gas cap there is a ridge under the seal, in the side of that ridge, close to the top of the cap there should be a hole to let air into the tank as the fuel runs out to the carb.
ok my needle has 4 grooves, i should go up and not down? I'm starting to think it's the float level and not the gas cap ventilation now because i tried to run it without the cap and it wouldnt start but every adjustment i make i try with and without the cap.
 

Mossy

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ok my needle has 4 grooves, i should go up and not down? I'm starting to think it's the float level and not the gas cap ventilation now because i tried to run it without the cap and it wouldnt start but every adjustment i make i try with and without the cap.
Up the noches should make it richer... I would see what the flow looks like into a bottle and clear that then get into the float and everything else after I know I have fuel flow...
 

DAMIEN1307

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Up the noches should make it richer
No Mossy, lol... the Top notch or groove for the C clip is the leanest setting not the richest,...lol... if the OPs needle is only 4 notches and he was second from the top, i would be now putting it on the top notch...Its an odd ball needle for a stock carby to only have four notches though.

Slide Needle Grooves.JPG


EDIT...Have you also adjusted out all but a 16th of an inch of freeplay on the throttle using both ends of the cable adjustments???
 

Chainlube

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No Mossy, lol... the Top notch or groove for the C clip is the leanest setting not the richest, if the OPs needle is only 4 notches and he was second from the top, i would be now puting it on the top notch...Its an odd ball needle for a stock carby to only have four notches though.

View attachment 169379
Not really an odd ball needle, a lot of the early speed carbs had four notch needles.
 
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