Fordson Won't Start

Is a simple replacement of the voltage regulator, etc. possible on this tractor? I"d like to upgrade the electrical system with something more state of the art and put a new wire harness on it. Of course my problem may be the starter motor itself, not the electronics, but I"d like to get the electrical system upgraded in any event. Your responses will be appreciated.

Have you cleaned the terminals?

There is a switch on the top of the starter with two wires. Have you tried bridging the wires and seeing if the starter spins? ENSURE THE TRACTOR IS NOT IN GEAR WHEN YOU DO THIS!!!

Try a wire from the LIVE pole on the battery to the solenoid small terminal. Starter should spin but not engage! SEE ABOVE FOR SAFETY POINT!!!

These problems will not be related to the voltage regulator or dynamo. It is possible to wreck both battery and dynamo by carrying out adjustments to the voltage regulator without the correct setting sequense or volt/amp meters.

Here is what I've done so far, without any positive results: cleaned terminals, bridged the two little terminals on the starter engagement switch and checked wires for breaks. The little rubber boot that covers the starter switch is torn off, and I'd like to remove that unit and replace the boot. Do you think that mechanism could be faulty and in need of replacement? And is it the kind of thing that is readily available?

At this point I am groping.

Thanks.

You can get the started solenoid from you local NH dealer, they are approx 30$.

The boot and electronics that sit on top of that starter are all one unit so you just cannot buy a boot ( just bought one a few months ago ). Now hold yours shorts, the boot / electronics on top of the starter is about 120$ and it is also available from NH. Bare-Co has the solenoid but I am not sure if they have the boot as there prices are usually a little better than NH. Bare-Co's web site is www.bare-co.com and if you need to order the parts call Moore Tractor at 1-800-754-9545 ( I am not a salesman for them, they have just treated me very well ).

Good Luck,

Scott

If you got nothing when you bridged those wires you have no power from the battery. If you've bridged the little wire on the solenoid and have not motored the starter I would suspect the solenoid has failed.

I will send you an E-mail with the wiring diagram.(if your address is on site, if not contact me at>Link

>Link

You can reach me at: professorjack@crestviewcable.com.

Don't know if this is pertinent, but one of the big terminals on the starter solenoid is a bit loose and wobbles from side to side. Is this normal?

Its just a switch on the top of the starter there are no electronics on that type of starter. When you push the starting lever, the contacts on the switch make and trigger the solenoid. This then switches the main power to the starter motor.

I think Sparex do the switch and the rubber cover but I don't think you need anything more that the solenoid. Do not use an automotive one as these are not capable of transmitting the amount of power required by the starter. They will work for a short time and then burn out.

The black box that is bolted next to the air cleaner is the voltage regulator.

The stater solenoid is the round device that your battery is wired too, there should be two big terminal and a small terminal. The battery should be wired POSITIVE GROUND unless it has been changed by you or the previous owner.

Scott

I believe the previous owner(s) have changed this unit to a negative ground, as the negative cable from the battery is bolted to the engine. I've read on this site, long ago, that most of the older units are so rewired.

Am I to conclude that the small cylindrical device mounted between the firewall and the air cleaner near the voltage regulator, attached to which there are several wires both large and small, is the starter solenoid?

Thanks for your help.

Jack

Jack,

Yep that is the starter solenoid. The original will have all three posts on the top. I have a replacement and it has them on the sides and you should be able to get one from your local NH dealer if you beleive it is bad. If your is original it should be similar to B3876 in the above pic.

Majorman can explain more about the electrical system on the major more that what I can but from what I know and have seen your starter will work whether the battery is setup as negative or positive ground. The only issue with setting the tractor up as negative ground is that the voltage regulator is setup as negative ground and it will not charge the battery correctly unless you get a new voltage regulator ( I think ) and then change the polarity of your dynamo. If that is something you want to pursue Majorman can give you the correct steps.

Scott

I have seen a few times on cars were the lights will light up but the car won't fire. Having a good battery on a diesel is alot more critical on a gasser since they don't have spark plugs.

Thanks,

Scott