6v to 12v conversion ... ignition problem

Yale Model #: KG51T-20H Serial #: 512736
Engine: International Harvester Model # U2A-LQ4B Serial #: UAAM 25574

Supposedly, this engine was used in FarmAll Super A and Super AV series tractors.

I have replaced the battery and the ignition coil with a 12v internal resistance model from NAPA. I have disconnected the wiring harness except for battery to solenoid to starter, and battery thru external on/off switch to + side of coil. The – side of coil is connected to distributor and a remote starter is connected to solenoid. Everything else disconnected.

In the process of trouble shooting I have replaced points, condenser, rotor, distributor cap, and plug wires. I have a 12 v trouble light connected to the – side of the coil and it flashes as one would expect to show the points are closing (and field collapsing).

IF I remove the plugs, ground them, and connect them to the plug wires the following is observed:
The plugs will not fire when the starter is engaged. However, the plugs do fire as the engine continues to rotate (thru inertia) after the starter is disengaged (remote starter button released).

Does anyone have any idea what I am doing wrong?

Randy Glasnapp
Overland Park, KS

I was getting almost a 6v drop while starting and apparently this was enough of a voltage drop to make the coil not fire. While I knew I had an old battery I thought the Commercial Heavy Duty battery charger/starter would provide enough volts and amps. I thought the starter would have dropped off line before the coil didn't get enough power to operate ... I was obviously wrong.

I connected another battery directly to the coil and the plugs fired as advertised. Unfortunately, I couldn't get the engine to start even with starter fluid ... but at least now the plugs are firing at the proper time.

Next step is to get a new battery and look at my carbureation system.

By the way, regarding the connections to the solenoid ... I had disconnected the wiring harness as I did not want the 12v to power 6v controls/gauges/sensors until I had the engine running on 12v. I wanted as simple a system as possible.

Thanks for your help and insights ... Randy

If it isn't you need to remove distr and rotate rotor to No1. Your firing order is 1-3-4-2 and the wires should be like this on your distr cap if the rotor rotates CW: Hal
2-1
4-3 and like this if it rotates CCW:

1-2
3-4

I am getting this 1951 Yale forklift running for my fathers estate. Any idea on how to figure out how much it is worth?

Randy

An instant test is to run the ignition off of a seperate battery from the one used to start it.
If ti runs, the above is probable cause.

I like to use a resistor style coil with a MoPar, or Chev ballast resistor to the key. And a resistor bypass wire from a Ford type 4 post solenoid, on the "I" terminal. This gives the coil 10-11 volts while starting, and then drops it to about 6-7 volts in operation.

Good luck, JimN