I am fixing 85 atc200s someone gave me. I got it running runs great but the carburator bowl is overflowing gas out of overflow line. I have taken apart carb and cleaned the float seems to move freely and i tested in gas to make sure it floats or It could be the float valve. I just wanted to know if anyone else has had this problem and I dont want to purchase expensive carb parts if not the source of problem. Thanks

 

Are the needle and seat in good condition? When the fuel is running out, try tapping on the carb to see if it stops. Also as I recall, the needle is spring loaded, does the needle still compress / expand?

 

Yes the needle and seat appear to be in good condition it is spring loaded. Spring moves freely. thanks

 

The only other thing that I would suggest would be to remove the boal from the carb with the carb still on the motor if possible.
Place a large rag below the carb, turn on the fuel **** and work the float with your finger to see if the fuel stops flowing when the float is all the way up. This way you can at least visualize and confirm that the needle and seat are mating and sealing properly.

 

Thats a good idea. I did not think of that. Ill let you know outcome thanks.

 

Similar idea... I just turn the carb upside down so that the float valve should be seated and blow in the gas line. If you cant blow through with the float up the valve is fine. The float should sit a couple degrees above vertical with a good valve... so if you hold the carb upside down so and horizontal and the float sags the valve should be replaced. You can buy an entire rebuild kit for around 16 bucks, but DONT buy the moose one- the valve they give you isnt right.

 

I ran water through their last night and it stoped when float was up. If I hold the carb upside down the float does sag Its not vertical but if you look close the float has a stop on it and it is resting on the stop.

 

You may want to have a look at the fuel filter on the fuel **** to see if its in good shape and sealing properly at the base. I had a similar problem with fuel pouring out of the overflow, I removed / checked / cleaned carb several times and it would work okay for a little while then the problem reocured. turned out the filter was bad allowing debris to enter the carb and hang up the float valve. a small inline filter resolved the issue.

 

you probably would have checked this, but are you sure the float is sealed and doesnt have any fluid in it? Also... does it overflow whenever the gas is on, or just when it's not running? Is there a steady stream or a little trickle?

The spring on the top of the needle should be holding the float up when the carb is upside down. Maybe it's too tired and the valve doesnt close soon enough.