1020 gas can't keep it running

[Sedgehammer]

Hoping I can get some input in this hair puller. Tractor has been having issues for a few years, but it's steadily getting worse and now has become unusable.
Relined fuel tank, put on a new coil and rebuilt the carb last year.
Replaced fuel pump, filter, gas, distributor cap, points, condenser last month and last night replaced intake/exhaust gaskets, as there was a small leak on the front intake. Checked gas line filter this morning, cleaned it, wasn't very dirty.

It now readily starts. Could hardly get it started before this. Only kinda runs with the choke out. Will run for about 8 seconds and it wants to die, so the gov starts to kick in. Once warm will lope 5 or 6 times, then almost die, then go back to loping. When cold I need to keep my hand over the inlet on the carb to get it running after it starts till it gets warm.

Help, please......

 

[Bayfisher]

when u rebuilt the carb did u chk to see if float had fuel in it, should be a brass float thats known to leak and sink, if leaks replace it.

if above is good and float has been properly set parallel to inverted carb flange then adjust main fuel mixture valve as needed to acquire clean running engine.

 

[defranks]

Do you have access to a remote tank? I have one that I use for motorcycle work, just a quart plastic bottle with a petcock on it to let fuel flow to the carb when the gas tank (of a bike) is off for maintenance. You can jury rig something if you don't have one.

What you're describing sounds like fuel starvation. Try using something like the remote tank I just mentioned, gravity feed to the carb fuel inlet pipe. If the tractor runs with that then you know there's a fuel delivery problem. A second check of that would be a brief shot of ether down the carb barrel(s). If it fires right up and runs for an instant.... fuel.

Have you disconnected the fuel line from the carb and cranked the tractor? Fuel should come out with considerable force. (Point it away from you or any hot surface.) When the carb was rebuilt was it thoroughly cleaned? The tiniest bit of dirt can do exactly what you're describing.

Keep us updated on this one, I'll be interested to know what you find.

 

[Sedgehammer]

Really good fuel pressure at the carb. If you crack the line while cranking it, it squirts out hard, so don't understand how it could be starving for fuel, although I agree with the symptoms.

Update, the neighbor checked his carb kit order. There was no new float. Will check that next.

 

[AWSubie]

I just went through a similar exercise on my Ford 2N; I had rebuilt the carburetor and the tractor ran essentially the same as you are describing. In my haste to get the tractor up and running again I skipped the step of chasing the passageways in the carburetor with a brass or aluminum wire when I was rebuilding. There must’ve been an obstruction because after I removed the carburetor for a second time and chased the all the passages, the tractor ran fine.

 

[Roadworthy]

Disconnect the fuel line at the tank. Does fuel flow freely and continue to flow freely? On an old vehicle you could have a blockage restricting flow out of the tank. If this works well try the same thing by disconnecting the line at the carburetor. If you have consistent free flow at this point your carb can get fuel. Be sure the float in the carburetor moves freely and is indeed taking the needle off its seat. If all this is good get a can of Sea Foam and a small external tank. Mix the Sea Foam about 50/50 with gasoline and try running the engine off this mixture. If it runs a few minutes and dies go do something else. Try it again the next day. This gives the Sea Foam time to clean passages in the carburetor. I've had really good luck with Sea Foam and old carburetors. I'll do that when all else fails.

 

[Sedgehammer]

It has a mechanical fuel pump, don't think it'll free flow. I can pump fuel out of the fuel line at carb like nobody's business when cranking. Have sea foam. Well remove carb, check float and all passageways next.

 

[Sedgehammer]

Tore carburetor apart today. Was some rusty fuel in bowl, so I'm assuming it was waterish. I also noticed that there was a small line that went from the intake butterfly to the choke butterfly wasn't hooked up when i got the carb off. I'm not sure if it was hooked up before or not (neighbors tractor). He rebuilt the carb this winter. all passageways were clean. Float doesn't leak. Will put it back together tomorrow.

 

[jaxs]

Before reassembling carburetor,make sure the passage from line inlet to needle and seat is clear. There might be an old filter or pieces of filter in the passage. If it act's the same when you get it back togeather,spray starting fluid or carb cleaner into air intake. If that doesn't keep it running,fuel isn't the problem.

 

[denchen]

Sounds like fuel hight in the float chamber. It`s a pity you cannot get the float one click higher.

 

[Bayfisher]

the fuel tank could be rusting internally, water in gas/diesel is always an issue, your friend might want to consider installing a fuel/water separator with a clear bowl between the fuel pump and the carb, this will allow him to see the water and drain it out of the system before problems arise, here is my setup.

 

[jaxs]

the fuel tank could be rusting internally, water in gas/diesel is always an issue, your friend might want to consider installing a fuel/water separator with a clear bowl between the fuel pump and the carb, this will allow him to see the water and drain it out of the system before problems arise, here is my setup.

That's a very good add on filter/separator:thumbsup: but I recommend it be plumbed in before fuel pump. That will prevent rust or other abrasives going through pump and causeing wear. Water separation is also more efficient on suction side of pump. The cherry on top is that expensive original filters last much longer since that little guy will catch 90% of trash before it can reach original filter.

 

[Sedgehammer]

Tore carb apart. Only thing I can see is the float closed a little too far. Will adjust this. Question, will have cause this problem if float is too close? We have a lack of air, rather than too much fuel since if we cut the air it'll run better and only runs with choke out.
Fuel tank was just repaired. I think issue would be from his fuel cans. Has inline fuel filter. I'll suggest a water separator, but doubtful he'd do it.
runs on either. It's definitely fuel related.
Contemplating buying after market carb. No rebuilt ones for sale I can find.

 

[defranks]

I still believe you have fuel STARVATION. When you cut the air to make it run better you're making the fuel mixture richer. That's what a choke does, too, it restricts air flow so the mixture becomes richer. (There's a smaller volume of air flowing through the venturi but at a higher velocity, causing more fuel to be mixed with that air.) I'm not sure what you mean when you say the float is "closed too far", but I assume you mean it's set too high so the fuel level in the float bowl is a tiny bit high. That won't cause the problem you describe. If the float is set too low then it's possible to have too little fuel in bowl and that will show up at high throttle settings or perhaps when the tractor is running on a slope. If the fuel level in the bowl is so low that no fuel is drawn at all, then the tractor won't start at all.

If it were my tractor, I'd put some gas right down the carb throat and try starting it. (Keep a rag handy in case the tractor backfires.) Don't put a lot of gas down the carb throat, just a couple of tablespoons full. If the tractor starts and runs for a few moments then dies, you know you aren't getting fuel mixture into the cylinders.

Remember that when the tractor starts and idles it's using the carburetor's low speed circuit, not the main jets. Only as the throttle opens up above about 1/4 to 1/3 open do the main jets begin to provide the primary fuel load.

 

[AWSubie]

Have u checked the main power adjustment screw and the idle air mixture screw for the initial settings?

Typically after a rebuild these screws are turned in (gently) until they seat and backed out around 1 1/2 to 2 turns.

 

[Sedgehammer]

Just put carb back together. Can make it run briefly (5 seconds) if I hold my hand over the carb and fuel runs out of the intake and then I remove my hand, it'll run.:hissyfit: :hissyfit:

 

[Sedgehammer]

I still believe you have fuel STARVATION. When you cut the air to make it run better you're making the fuel mixture richer. That's what a choke does, too, it restricts air flow so the mixture becomes richer. (There's a smaller volume of air flowing through the venturi but at a higher velocity, causing more fuel to be mixed with that air.) I'm not sure what you mean when you say the float is "closed too far", but I assume you mean it's set too high so the fuel level in the float bowl is a tiny bit high. That won't cause the problem you describe. If the float is set too low then it's possible to have too little fuel in bowl and that will show up at high throttle settings or perhaps when the tractor is running on a slope. If the fuel level in the bowl is so low that no fuel is drawn at all, then the tractor won't start at all.

If it were my tractor, I'd put some gas right down the carb throat and try starting it. (Keep a rag handy in case the tractor backfires.) Don't put a lot of gas down the carb throat, just a couple of tablespoons full. If the tractor starts and runs for a few moments then dies, you know you aren't getting fuel mixture into the cylinders.

Remember that when the tractor starts and idles it's using the carburetor's low speed circuit, not the main jets. Only as the throttle opens up above about 1/4 to 1/3 open do the main jets begin to provide the primary fuel load.

Yes, too high. Just fixed that.
Runs on either. Did run after I flooded it with my hand over the carb intake. Had gas running on the ground. while the mixture can be off, not seeing how it could be starving. There was gas running out of the carb. There's lots of gas at the filter 90°. There must be something preventing getting the mixture to the motor. I have no clue what that could be. It has fuel.

 

[Sedgehammer]

Have u checked the main power adjustment screw and the idle air mixture screw for the initial settings?

Typically after a rebuild these screws are turned in (gently) until they seat and backed out around 1 1/2 to 2 turns.

Yup. Not sure about when it was rebuilt.

 

[defranks]

"Runs on either. Did run after I flooded it with my hand over the carb intake. Had gas running on the ground. while the mixture can be off, not seeing how it could be starving. There was gas running out of the carb. There's lots of gas at the filter 90°. There must be something preventing getting the mixture to the motor. I have no clue what that could be. It has fuel."

When I say fuel starvation I mean that the air fuel mixture is not getting to the cylinders to be burned. You can have plenty of fuel AT the carburetor, but no fuel flowing THROUGH the carburetor. The fact that it starts and runs on ether, and that it runs after you flood it tells you that spark and compression are there and correct, and that the engine will run when it has something to burn. So no fuel is making it into the cylinders.... fuel starvation.

Perhaps one of the small passages in the carb is blocked. Sometimes the wrong gasket can be installed and block a fuel or air passage.

Is there a filter screen inside the carburetor at the fuel input? If you saw rust in the float bowl, then it could be that the internal screen (filter) is plugged.

It might be well to start from scratch. Go buy a new carb rebuild kit and make sure it's the correct kit. Carefully check every passage in the carb. I like to blow carb cleaner through those passages to see that it sprays out the other side. (Keep your face away, trust me, carb cleaner burns the eyes!) Make sure that no passages are blocked by gasket material or sealer.

Good luck!

 

[Sedgehammer]

"Runs on either. Did run after I flooded it with my hand over the carb intake. Had gas running on the ground. while the mixture can be off, not seeing how it could be starving. There was gas running out of the carb. There's lots of gas at the filter 90°. There must be something preventing getting the mixture to the motor. I have no clue what that could be. It has fuel."

When I say fuel starvation I mean that the air fuel mixture is not getting to the cylinders to be burned. You can have plenty of fuel AT the carburetor, but no fuel flowing THROUGH the carburetor. The fact that it starts and runs on ether, and that it runs after you flood it tells you that spark and compression are there and correct, and that the engine will run when it has something to burn. So no fuel is making it into the cylinders.... fuel starvation.

Perhaps one of the small passages in the carb is blocked. Sometimes the wrong gasket can be installed and block a fuel or air passage.

Is there a filter screen inside the carburetor at the fuel input? If you saw rust in the float bowl, then it could be that the internal screen (filter) is plugged.

It might be well to start from scratch. Go buy a new carb rebuild kit and make sure it's the correct kit. Carefully check every passage in the carb. I like to blow carb cleaner through those passages to see that it sprays out the other side. (Keep your face away, trust me, carb cleaner burns the eyes!) Make sure that no passages are blocked by gasket material or sealer.

Good luck!

Agreed on not getting to cylinders.
Yes, possible.
That's clean.
Yeah, was thinking of that also vs buying a new carb. My hesitation there is this has been doing this over a couple years, although not as bad. I didn't rebuild the carb this winter and I'd put it back together as it was taken apart, so if the problem lies there, I won't know what that is possibly.