1964 ford 4000

Hi this is my first time on a forum, yal have a lot of interesting posts. I have a ford 4000 that I inherited from my grandpa, it has sat in a shed for the last 10 years, I had a reputable local company go through the tractor and replace the fuel tank screen and sedament bowl, new spark plugs and wires, go through and get the motor unstuck, and go through the hydraulics to get them working. They got it back to me and it ran pretty well, I ran it here and there a few times the next year or so, and it ran ok. I put my brush hog on it and tried to mow my pasture, it ran well for the first 30 minutes or so and then started to act like it was going to die, then it would rev up and then repeat the process for a few minutes, then it would only idle and if I gave it any gas it would die immediately. It will always start right back up so I don?t think it is vapor locking. So I replaced the fuel in the tank with non ethanol gas and added sea foam, and emptied the sediment bowl. I stared it up and it did the same thing as before, I adjusted the float on the bottom of the carburetor and it made the motor run better for a bit then it went to an idle and if I gave it gas it would die, I also screwed the screw all the way shut on the top of the carburetor that initially made it run better. Please help, thank you for your time and have a great day!

Welcome Ben!

Sounds like you need to do some basic trouble shooting. Best time to do it is when it is acting up. Carry some tools, be ready ASAP when it fails.

The symptoms you describe can be either weak spark or fuel starvation.

First take a look at the points. Be sure they are properly gaped, check the distributor shaft for side play. It should have very little play, otherwise the points will not stay set. Today's ignition components are all aftermarket, most are poor quality imports. Not uncommon to be bad out of the box. If in doubt, replace the points, try an old condenser if you have one.

Check the spark at the plug end of each wire. It should have a blue hot spark that will jump at least 1/4 inch. Feel the temperature of the coil. It should not be any warmer than the surrounding parts. If uncomfortable to hold, it's too hot. Could be failing, could be the wrong coil.

Once satisfied with the ignition, move on to the fuel.

When it acts up, have you tried a partial choke to see if it improves? If so, chances are it is lack of fuel.

Try loosening the fuel cap. Even if it says "vented", it may not be.

I think that one has a fuel pump. If so, disconnect the line from the carb, aim the line into a container, crank the engine. It should give a strong shot of fuel every time the pump cycles (every other time the engine turns through). If low flow, or a trickle, the pump is bad or there is a restriction ahead of the pump. Fuel should gravity free flow to the pump.

There is a drain plug in the bottom of the carb. Have a clean container ready, start the engine, let it idle. {If no fuel pump, do the test not running). Remove the plug, catch the flow. There should be a steady flow, not a drip or stop flowing. There may be a screen in the fuel inlet fitting at the carb. Be sure it is clean.

Look at what was caught. If dirty, rust chunks, the same will be inside the carb. It may need to come off and be cleaned again. If the tank is contaminated it will need to come off and be rinsed out. If extremely rusted or pin hole leaking, it will need to be replaced.

Here's the bad news...

Some of those came with Holly carbs. They are notoriously difficult to repair and keep running. If it has a Holley, your decision, give it your best shot, or replace it with a rebuilt Zenith. The rebuilt carbs are better than the new aftermarket.

Hope this helps, let us know...

Like Steve said, you need to troubleshoot the problem rather than take a shotgun approach. If the engine isn't getting enough fuel, it will usually run better when you pull out the choke a bit. I suspect the problem is spark rather than gas, but you need to isolate the problem to either ignition or fuel before you can fix it.