Farmall 400 misfire and power loss

[Mr C]

I recently inherited a Farmall 400. I hired someone that told me he could perform an oil change an tune up. I had no idea the last time any maintenance had been done on the tractor. Prior to the maintenance work the tractor ran great.

Now after the maintenance work the tractor back-fires, flames will shoot out of the exhaust when under load or the engine is revved up. The tractor also does not have the power to disc a small food plot. This did not occur prior to the work on the tractor.

This is what has been done. The oil has been changed, new plugs and a new distributor cap. There were also new wires put on. The wires that were put on are the type that are to be cut to length, stripped and clamped on to a fitting. The wires were assembled but never cut to length. They are cable tied together. As for the gas, it is old. The tractor has been stored outside, under a shed protected from rain and snow in northern Wisconsin.

Any ideas on the problem. I have been told it could be the gas or the wires on the cap are not in the correct order. I do have the manual on the tractor.

[Eugene]

Welcome.

Spark plug wires on two wrong spark plugs. First guess.

Ignition timing. Second guess.

Tractor runs, bad gas would not be on my list of potential problems.

Ask for the labor money back. Pay for the parts. You didn't get a full tune up; compression tests, valve tappet adjustment.

[Mr C]

Thank you much. I will check the plug wire order.

[Mr C]

For Eugene, as you suspected, it was spark plug wires on two wrong plugs. Runs great now. Thanks for the help.