Hand start A fills cylinders with so much gas I can’t turn it

[Hawgwildtours]

I’ve adjusted the float to what I think is the correct level. I can pull the compression relief valves off the tractor and fuel will shoot out 5 feet. I got it to fire once with the compression valves off the tractor. It ran for about a minute maybe. This tractor has sit for about 7 years when I got it. Fuel was varnished. Cleaned carb and tank. Should I just keep messing with the float or is there something else that I am missing.

 

[ChrisInPA]

Are the needle valve and seat actually sealing? I’ve had a situation where they were not, which created a flooding problem similar to yours. In my case the new parts didn’t seal but the old needle valve and seat sealed.

 

[a49deere]

Best way to adjust the float or see if it's sealing is to put a hose barb and clear tube on bowl drain and hold it up next to bowl. Fuel will seek level that float allows. If needle is leaking fuel will go way higher than where it should be on the bowl.

 

[greenmech]

Maybe clean carb completely and check float. Could be too heavy with gas. New needle and seat may help. Ron MN

 

[Hawgwildtours]

Are the needle valve and seat actually sealing? I’ve had a situation where they were not, which created a flooding problem similar to yours. In my case the new parts didn’t seal but the old needle valve and seat sealed.

This might be it. I’ll try the old needle valve and seat

 

[Hawgwildtours]

Best way to adjust the float or see if it's sealing is to put a hose barb and clear tube on bowl drain and hold it up next to bowl. Fuel will seek level that float allows. If needle is leaking fuel will go way higher than where it should be on the bowl.

I’ll try it. Thanks

 

[a49deere]

I’ve adjusted the float to what I think is the correct level. I can pull the compression relief valves off the tractor and fuel will shoot out 5 feet. I got it to fire once with the compression valves off the tractor. It ran for about a minute maybe. This tractor has sit for about 7 years when I got it. Fuel was varnished. Cleaned carb and tank. Should I just keep messing with the float or is there something else that I am missing.

What is your starting procedure? I know on the two "A"'s that I own, one hand start the other electric start, you want to give it a touch of throttle, full choke, and most importantly, as soon as you get that first POP, off with the choke. They flood really easy! The other question is how high are you adjusting the float level in relation to the top of the bowl? I believe it should be 3/8-1/2" below!

 

[Fixingfarmer]

Check float as well for leaks I’ve had one with pinholes on top of it would slowly fill with gas. The way I found it was submerge the float see if it bubbles the air out

 

[Hawgwildtours]

What is your starting procedure? I know on the two "A"'s that I own, one hand start the other electric start, you want to give it a touch of throttle, full choke, and most importantly, as soon as you get that first POP, off with the choke. They flood really easy! The other question is how high are you adjusting the float level in relation to the top of the bowl? I believe it should be 3/8-1/2" below!

My startup process could be the problem. This is a new to me tractor and I have never started it before. I will try your steps next time. I’m getting closer. It had bad gas and no spark. Solved both those problems but after turning the flywheel for about 15 minutes I’m all done for a while. Thanks for your help

 

[lodoc]

but after turning the flywheel for about 15 minutes I’m all done for a while.

Never had an A but watched vid on starting procedure. Gotta give them ole farmers credit...

 

[a49deere]

My startup process could be the problem. This is a new to me tractor and I have never started it before. I will try your steps next time. I’m getting closer. It had bad gas and no spark. Solved both those problems but after turning the flywheel for about 15 minutes I’m all done for a while. Thanks for your help

Once it remotely pops once, OFF WITH THE CHOKE, they flood easily, thus your gas from petcocks! Once you flood them you may as well go sit and have a few beers to refresh yourself!

 

[miangus]

Be very careful if you remove the plugs and roll it over to clear the cylinders, make sure you securely ground the plug wires. As others have said your needle valve is not closing correctly. Could be; adjustment error, bad float or a bad needle or seat.

 

[ss55]

I’ve adjusted the float to what I think is the correct level. I can pull the compression relief valves off the tractor and fuel will shoot out 5 feet. I got it to fire once with the compression valves off the tractor. It ran for about a minute maybe. This tractor has sit for about 7 years when I got it. Fuel was varnished. Cleaned carb and tank. Should I just keep messing with the float or is there something else that I am missing.

Agree with adjust the carburetor float and check the needle valve seat.

Did some of the later two cylinder John Deere tractors have automatic fuel shut off valves that opened by engine oil pressure? Now-a-days a solenoid wired into the ignition circuit can do the same thing. A manual quarter turn ball valve works well too.

G

Thread 'automatic fuel shut-off!'

Mar 12, 2010

i have a jd 520 with the original auto fuel shut off. seems it has malfunctioned and i have got gas in crankcase. have any ideas on a fix?
i would like 2 keep it original but at the same time i dont want 2 have 2 worry about this again.

• greenfeverms
• Replies: 11
• Forum: John Deere

https://www.yesterdaystractors.com/cgi-bin/viewit.cgi?bd=jd&th=60318

 

[Fordy20]

If your cylinder is filling with gas, best check for gas in the crankcase before trying to start it. My 620 did this once and it has a screw in dipstick. When I unscrewed the dipstick, gas shout out and also one cylinder was full. I have a magneto on my G so I just let that run out of gas to stop it. Lately, I've also started letting the 620 run out of gas before turning off the ignition. They start a lot better that way - usually on the first shot. With a gravity fuel tank you really need to shut the gas off every time you park it.

 

[miangus]

If your cylinder is filling with gas, best check for gas in the crankcase before trying to start it. My 620 did this once and it has a screw in dipstick. When I unscrewed the dipstick, gas shout out and also one cylinder was full. I have a magneto on my G so I just let that run out of gas to stop it. Lately, I've also started letting the 620 run out of gas before turning off the ignition. They start a lot better that way - usually on the first shot. With a gravity fuel tank you really need to shut the gas off every time you park it.

All the original As with mags required the fuel to be shut off to shut down the tractor.