Ford 641 Carb...help!

[cab72111]

I have 641. I can let the tractor sit for a day and try to start it and it will run for about 30 seconds...only if I keep it choked. I took off the carb and cleaned it and reinstalled it. It will run if I keep my hand over the breather hose...which I am assuming is making it suck more gas in. What is wrong and what should I do? It just started doing this.

 

[Clay8Ns]

Have you checked the glass fuel bowl to see if it is full of rust?Also when you remove the bowl make sure you check the screen also.My 640 does the same thing sometimes.

 

[old]

I would first off try this. Pull the drain plug out of the bottom of the carb, catch the gas so you can look at it to see if theres dirt or water in it. You need to let it flow for at least 5 minutes and it should have a good steady flow. If it doesn't work back till you find where you loose the flow. You could also have a float that is sticking or set wrong or a sticking needle in the float seat.
Hobby farm

 

[souNdguy]

either a really plugged main jet.. or a really bad vacume leak.

soundguy

 

[dale9n]

I too have the 640, and have had fuel issues. You have to make sure the idle screw is set proper. turn it all the way in, not too tight, then back out one turn. adjust it in a little to get in tuned in once its running. clockwise is in. the vacuum leak point is possible too. take the advice given to watch the gas flow out of the drain plug hole. not only look for trash, but it needs to be flowing well. Let enough run out to empty the bowl then see if the new gas coming into the bowl and out the hole is flowing right. your running out of gas up the intake. you just have to keep looking for the cause. hope you find it soon. dale in va.