Farmall Super A starting issue

[browning1]

Recently bought a Farmall Super A with the C-123 engine at at auction that had been sitting outside for at least 10 years. Put fresh gas and a battery in it and engine would just turn over. After cranking it a few times I noticed gas was coming out of the carburetor inlet at air cleaner. Put a rebuilt kit in carburetor and tractor fired up and ran. I turned tractor off and tried to start tractor back up and tractor would not start back up. After trying to start tractor a few times gas started running out of the carburetor inlet once again just like before i rebuilt carburetor. I have only been able to get this tractor to run a handful of times and every time it cuts off it will not restart and gas starts coming out of the carburetor intake. The is a Zenith carburetor and when i rebuilt it i followed the rebuild instructions on setting the float, idle and main jet settings. when trying to restart it might hit once or twice. I have even trying cutting gas off and staring it to use up extra fuel in carb but still only will hit once or twice. Sorry this is a long post but this is getting frustrating. Also i did put a Pertronix ignition and a new hot coil, wires and rotor button it also. tractor was already converted to 12V.

[Don McCombs]

The Super A has an updraft carburetor. This means the atomized fuel from the carburetor is drawn up into the manifold by vacuum created by the rotating engine. In a “no start” scenario, the un-ignited fuel has no where to go other than back down through the manifold and carburetor and out the air intake. This is a perfectly normal circumstance. I would explore ignition or compression issues as a source of the non-starting behavior. A tractor that has set for ten years is likely to have stuck valves and/or electrical continuity issues.

[Eugene]

Also I did put a Pertronix ignition and a new hot coil, wires and rotor button it also. Tractor was already converted to 12V.

Remove the electronic ignition system and reinstall the original points, condenser, and coil.

Compression tests and diagnose the ignition problems.

[browning1]

I did check the compression to my surprise all four cylinders were showing 115 to 120 psi. That was with spark plugs out, cold engine, and cranking each cylinder over three times.I was figuring the compression would be around 75 to 90 psi. I actually drove this tractor around for awhile so i wouldn't think it would be a stuck valve.

[Eugene]

Still not starting?

If so, check your ignition. Actually, was the not start situation after you installed the electronic ignition?

[browning1]

No it wouldnt start before putting eletronic ignition. I put D21 spark plugs in also. I do have a whole new wiring harness for it on the way because the 12v converion wiring used is in rough shape. When i pulled spark plugs to check compression i noticed no. 1 and 2 spark plugs where coated in carbon while 3 and 4 were fairly clean looking

[Gary Dotson]

Does this tractor have a ballast resister? If so, is the Pertronix connected to the switch side of the resister? It needs full system voltage to function properly. Also, the hot coil concerns me as well. I know Pertronix sells them for these systems but I’ve had issues with them. I prefer to use the stock coil, assuming it is serviceable. It’s also very important to follow their instructions carefully, concerning coil ohm values and proper wiring connections. Of course, you need to set the timing properly.

[Lt.Mike]

Also I did put a Pertronix ignition and a new hot coil, wires and rotor button it also. Tractor was already converted to 12V.

Remove the electronic ignition system and reinstall the original points, condenser, and coil.

Compression tests and diagnose the ignition problems.

I’d agree with this. Points are a lot easier to diagnose and correct if there is an issue but you’d find that they are pretty reliable.

[browning1]

Well i figured out the problem. Spark plug wires on wrong. Engine runs great now.

[Gary Dotson]

I’m glad you didn’t have to abandon the Pertronix. I have installed a bunch of them and they have been very reliable for me.