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Discussion Starter · #1 ·
I have a 1948 Farmall Cub that has supposedly been sitting since around 2016 and I've been trying to get the engine to start and run but it will not start. Also the entire time it was sitting the fuel tank was completely empty and the carburetor was drained, but there was fuel in the bowl under the tank which I immediately dumped before trying to do anything. The problem I'm having is the engine turns over nicely and then it'll almost start and then the stater disengages and the engine doesn't start. I changed the spark plugs cleaned the cap and rotor and then checked the spark and it was a very bright blue, and then I changed the fuel filter. I'm thinking its a carburetor issue but I don't get why it'd have a problem if it was sitting without fuel in it the whole time. I don't know what else to do except for rebuild the carb but I'd rather not unless I have to.
 

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Remove the carb bowl plug. Have a jar or suitable container to catch the gas. If you do not have a steady stream of gas you have a blockage somewhere. Those fuel systems were not designed to work with an inline fuel filter if you have one. There is an internal strainer where the fuel line fastens to the carb. Check it to see if it is plugged. The sediment bowl valve could also be plugged. If both of those are clean an inline fuel filter is not needed, and often can cause problems. Also make sure the gas cap is vented.
 

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Discussion Starter · #3 ·
Remove the carb bowl plug. Have a jar or suitable container to catch the gas. If you do not have a steady stream of gas you have a blockage somewhere. Those fuel systems were not designed to work with an inline fuel filter if you have one. There is an internal strainer where the fuel line fastens to the carb. Check it to see if it is plugged. The sediment bowl valve could also be plugged. If both of those are clean an inline fuel filter is not needed, and often can cause problems. Also make sure the gas cap is vented.
Thanks for the information, I've drained the carb bowl multiple times and it's always clean and I know fuel is flowing from the sediment bowl valve at a steady stream. Also yes it does have an inline filter but it's a cheap one so I don't know that it'd restrict flow very much, but I could modify the old filter by removing the element so the fuel just goes right through. The cap is the original so yes it's vented and not clogged (basically just a hole straight into the tank).
Also just incase anyone is wondering its has been stored inside all year round for a very long time.
 

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If you know you have the right combination of fuel and properly timed spark.
After sitting several years, the next thing I would look for is valves sticking open.
 

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This might help you check them.
 

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Discussion Starter · #7 ·
If the valves were sticking would I be able to hear a ticking sound when the engine was turning over? Because when the engine is turning over the only ticking sound I hear is from the magneto, which as far as I know is completely normal.
Also the tractor is still a 6 volt system, I just thought I should mention that.
 

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May not be able to hear anything abnormal but should be able to see with the valve cover off.
Will It fire with a little shot of starting fluid?
 

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A compression test on each cylinder may be helpful. Have you checked the timing?
 

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Discussion Starter · #10 ·
May not be able to hear anything abnormal but should be able to see with the valve cover off.
Will It fire with a little shot of starting fluid?
It will fire and almost start on starting fluid but then the starter disengages.
I can recheck the timing but I'm pretty sure it's right because I made sure I put everything back where it was
 

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I have a farmall 300. It got hard to start and the starter would kick out I changed the points and plugs cleaned the sediment bowl. Still no improvement. I decided to replace the coil. That cleared the problem up. Starts easy now and the starter doesn’t kick out. Apparently the coil was strong enough to show fire but to week to fire the engine up
 

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It will fire and almost start on starting fluid but then the starter disengages.
I can recheck the timing but I'm pretty sure it's right because I made sure I put everything back where it was
I agree with checking compression--sounds like it may be firing on one good cylinder and that kicks out the starter, but the other cylinders may lack compression. If there are stuck valves , just holding a finger over a spark plug hole should tell you that
 
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