Ford 4610 MkIII tractor

[Ken Harris]

Hello,
I'm giving a neighbour a hand with his Ford tractor and would appreciate any help with the following.
The tractor developed what appears to be an electrical problem when trying to start it. The battery is OK, lights work etc but when the key is turned to the start position - nothing!
While the tractor is a fair age now it has only one owner, very low hours and kept in shed so is in pretty good shape overall.
I can start the tractor by 'jumping" the connections directly on the starter motor solenoid so have ruled out a problem there.
I think that it may be the switch or the wiring/connectors between the switch and the starter motor.
To abtain access to the switch and wiring, I have started to dismantle the hood but have run into difficulty removing the rear section over the fuel tank as it is fitted around the steering column.
I haven't been able to remove the steering wheel (probably never been off in 30 years) and there is a bracket which supports the gear selector mechanism which is a close fit over the cover which I may also have to remove.
I am not confident about disconnecting the gear linkages above the transmission housing as it may be tricky to reconnect them correctly?
If anyone has any experience or suggestions it would be much appreciated.
I don't have access to a shop manual for this tractor which makes it a bit difficult too.
I have a reasonable amount of experience working on these smaller tractors but mainly with Massey Ferguson's.
Thanks for any help offered,
Ken

[Tx Jim]

First check the neutral start switch located between the 2 shift levers in trans cover.

[Nouveau Redneck]

After the neutral switch, check the starter relay (solenoid).

[ssweet9c1]

I bet it's neutral safety switch... Unplug it for testing purposes but do not leave it that way (for safetly purposes)
Jonathan

[Ken Harris]

Originally Posted by Tx Jim

First check the neutral start switch located between the 2 shift levers in trans cover.

Thanks for the suggestions about checking the neutral switch. I have previously checked that and from my observations the power wire from the start switch runs via the neutral switch to the starter solenoid. With the plug in the wiring loop disconnected I can measure a closed circuit in neutral and an open ciruit when the selector is moved into gear so it appears that the switch would be OK. I presume that it has to be a closed ciruit to allow starting.
Also as I have been able to 'bypass' the key start by shorting between the power wire connector and the positive terminal, both on the solenoid it would indicate that the solenoid and starter are both working fine.
Any ideas about how to finish removing or at least lifting the rear part of the hood over the fuel tank to get access to the wiring and key switch below?
Is it safe to disconnect the gear linkages above the transmission housing and the selectors?
Thanks again,
Ken

[Tx Jim]

Just because you have continuity when neutral start switch is in closed position does not indicate 100% that the required voltage/amps is flowing through the NS switch. I recommend checking switch with volt meter or test light.

[Rolex]

I'm with Jim I always use a test light, at my place I had trouble with the native marsupials putting their teeth through the plastic coating then the wires inside corrode, when I use a voltmeter it will show a voltage but the wire will not carry a current, a test light will show this.

I have made a test box with three globes ranging from 5w to 55w for load testing wires and switches, it also has a beeper to test for dead shorts.

[Durham Farms]

I have the very same tractor, and also had problems like this when we first got it (used):

1) Check all connections thorougly. Even through you have voltage, you may not have enough power. If my battery is low, I have 12.6 volts, but it still won't start.

2) No need to pull the cover, shifter, etc. You can remove the proof meter and access most everything.