Ford 9N - Starts But Won't Start

Other than not starting with the starter the machine idles smoothly and has all the power a 9N should probably have.

The actual problem was right in front of my nose - the resistor was not connected to the power source, the wire had been disconnected and was hanging free after the system was changed to a negative ground. I connected the wire to the terminal block and it started, using the starter, immediately.

Some other interesting data I gathered:

1. Voltage on the system with the engine not running - 6.3 volts. Voltage at the starter when cranking - 4.7 volts.

2. Compression: Dry -- #1 90 psi, #2 -- 50 psi, #3 -- 90 psi, #4 -- 90 psi. Wet -- #1 110 psi, #2 80 psi, #3 -- 102 psi, #4 -- 105 psi. How concerned should I be about #2?

This 9N has a high/low range with the engagement device being a pull located on the dash of the machine. It is really geared down when in low range, 1st gear. The previous 9N I owned didn't have this feature and other N's I've looked at recently didn't have this feature. Was the high/low range common on 9N's?

When you pull-start the tractor, full battery voltage is available to the ignition circuit, but when you crank it with the starter, there is a significant loss of voltage available to the ignition system due to the load of the starter on the battery. That is why a weak ignition system will act up worse when the starter is used than when the tractor is pull-started.

Other possibilites: weak battery (even if it's new... check voltage while cranking with the starter), perhaps someone has used resistor (ignition noise suppression) spark plug wires, or a starter that draws way too much current.

Do a compression test.. dry then wet.. 5 puffs minimum.. each cylinder...

90 psi is the minimum ford spec.. with no more than 10 psi difference between adjacent cylinders.

While slightly lower compression.. i.e. 85 across the board is lower than ford spec.. still got lots of power.. However if you are seeing 50-60 across the board.. engine is a bit tired.

If wet reading is like 20 psi higher than dry.. rings/cylinders are probably wore.

Sometimes an N that sets a few years will get sticky valves and rings, than might unstick with some MMO soaking time.. however if this is a 'running' N.. sounds like it may need some work.

let us know what you find out.

Soundguy