8N electrical problem

gtreasur

New User
I need help. I recently purchased an 8N, not sure what year. It has been converted to 12V. It did not have a key switch on it, he said his son had lost the key to it so he had removed it and just had each end of the wires with a spade on them so you could put them together when starting. I purchased an original key switch for it on ebay and was going to replace it. When i did i noticed that it was hot all the time no matter what position the key was in, then i noticed that even with the switch removed and the wires hanging loose it still turned over when i pushed the start button. Then it stopped, nothing when i pushed the start button. After checking the voltage i noticed that the wire from the start button to the solenoid is always hot, even when it is not being engaged. Isn"t this wire supposed to be a ground? Have i somehow reversed the polarity or is it bleeding through somewhere? I"m not good with DC systems so any help would be appriciated. Thank you very much.
 
It sounds like you may have a dead battery or a poor connection at one or more of the battery cable connections.

And, YES, when wired "as-original", the starter will engage ANYTIME the tranny is in neutral and the tranny-top neutral-safety start switch is depressed.

And, yes, the wire to the "start button" is always "HOT", as the starter solenoid is an oddball setup Ford used "back in the day", and is internally wired that way, so simply GROUNDING the wire (by means of the "start button" will make the solenoid "pull in", activating the starter.
 
(quoted from post at 11:30:39 10/29/08) I need help. I recently purchased an 8N, not sure what year. It has been converted to 12V. It did not have a key switch on it, he said his son had lost the key to it so he had removed it and just had each end of the wires with a spade on them so you could put them together when starting. I purchased an original key switch for it on ebay and was going to replace it. When i did i noticed that it was hot all the time no matter what position the key was in, then i noticed that even with the switch removed and the wires hanging loose it still turned over when i pushed the start button. Then it stopped, nothing when i pushed the start button. After checking the voltage i noticed that the wire from the start button to the solenoid is always hot, even when it is not being engaged. Isn"t this wire supposed to be a ground? Have i somehow reversed the polarity or is it bleeding through somewhere? I"m not good with DC systems so any help would be appriciated. Thank you very much.
"After checking the voltage i noticed that the wire from the start button to the solenoid is always hot, even when it is not being engaged. Isn"t this wire supposed to be a ground? Have i somehow reversed the polarity or is it bleeding through somewhere? I"m not good with DC systems so any help would be appriciated. Thank you very much."
Yes, that wire is always hot....until you ground it by pressing the start button. Solenoid activating coil gets power internally from battery post of solenoid and you complete the circuit by supplying ground via starter switch. All is normal there. The key switch should only affect ignition, not starter switch. Even with ignition switch OFF, starter switch will activate starter motor.
 
Thanks, I just purchased a new battery and am getting 12 volts across the system, even at solenoid, but when i push the start button nothing happens. If i disconnect the battery and reconnect it, the first time i push the start button i can hear a click from the solenoid, then nothing. Any ideas?
 
That sounds like a bad solenoid to me. You can check it by jumping around the solenoid and see if the starter spins then. If not the starter is the problem.
 

Skip start switch & directly ground the small solenoid terminal. BE SURE in neutral or on tractor, in neutral, so as not to have it run over you!
 
To jump around it you take something like jumper cables and hook one to one of the big posts and the other end you hook to the other big post and that should make it spin over unless you have a bad starter or bad cable connections which from what you have said maybe your problem
Hobby farm
 
I jumped around it....absolutely nothing. Does that mean a bad starter? I tapped the starter a few times with a hammer just to make sure and still nothing.
 
Connect a 12-Volt test light between the terminal stud on the STARTER and the metal BELLY of the starter.

When jumping around the solenoid does the light light up as brightly as it does across the battery posts?

If NOT, you have a bad connection somewhere in the battery cables.

If it DOES light brightly with no activity from the starter, the starter has failed.

(You haven't "wrenched" on the stater's terminal post and torn the solder loose connecting it to the starter's windings, have you?)
 
You are getting 12.43 Volts, as measured between the terminal stud on the starter itself, and the metal "belly" of the starter, correct?

If so, two words... BAD STARTER.
 
You were right, got the starter off and jumped it with a good battery and some jumper cables, solenoid clicking in and out, starter deader than a doorbell, thank you very much.
 
To remove the starter, unscrew the bolts out of the block & put a nut on one of them. Otherwise, the starter comes apart. Not fatal, but not fun either. (tip # 36 at the link below) Then, loosen the two bolts holding the oil filter canister to the block, (it does not need to be removed) remove the dipstick, and keep the starter close to the block while pushing the front of it down and lifting the back up. Sometimes you have to remove the drain petcock as well.The bendix is behind the flywheel; your job is to get it over the flywheel.

Caution: while the starter is off, resist the temptation to screw with the bendix. If you extend the bendix, and it is not the OEM bendix w/ the big spring, you will have a hard time getting the starter installed.

To install the starter, keep it close to the block while pulling the front of it up and pushing the bendix back into the hole. The bendix has to go behind the flywheel; your job is to get it over the flywheel. Grinding out an egg shape at the 2 o'clock position before you put it back will make your life easier.

Lastly, while the starter is off, polish the block & starter mating surfaces w/ sandpaper to insure a good electrical ground between the two, and clean the mating surfaces where the starter's "belly" meets the aluminum endbell. The starter's ground circuit is through that "joint" as well was through the starter endbell-to-flywheel housing joint.

BTW......check out tip # 39 as well. The manuals will save you a lot of time & frustration.
50 Tips
 
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