Ford 8N - Electrical problem. No juice and ammeter buried into negative side.

[Midniteoyl]

Agree with soundguy.. Ammeter is bad. Short to ground.

 

[tmac196]

The tractor will start and run with the ignition key on and the battery connected whether or not the genie and/or the VReg are connected.

I will obtain a new ammeter today, I hope.

Were the wires connected correctly? Well, I took the time to carefully reconnect them the way they were once I had the gennie repaired and installed the new Vreg 7 weeks ago. At that time, per the manufacturers instructions, I polarized the gennie and this process seemed to work correctly. When the engine had enough revs, the Ammeter strayed to the right indicating current flow charging the battery. I did not feel the Vreg at that time, so I don't know if it was hot then.

While on the topic of wiring, how about a simple primer wiring discussion of what wires go to what structure. Gennie has ARM, FIELD and GROUND and these are wired to what, specifically? Vreg has ARM, FIELD and BAT. I can carefully chase the wires in the "harness" down when I reassemble and test the system to avoid wiring mistakes with some advice from all of you.

Thanks, again, for the help.

tmac

 

[MGBBob80]

I found these on the N Tractor Club website and thought that you might find them useful. N Tractor Club.

View attachment 8N- Wiring- Diagram-by-Jim-Lawrence.pdf View attachment Testing-Replacing-Polarizing-8N-Voltage-Regulator.pdf

 

[tmac196]

Thanks, Bob. The second PDF was helpful, but the first was for a 12 volt system. I am still running a 6v system in this tractor.

tmac

 

[MGBBob80]

Thanks, Bob. The second PDF was helpful, but the first was for a 12 volt system. I am still running a 6v system in this tractor.

tmac

Whoops... Sorry about that - I did know that you were on a 6 volt system.

I do have another set of schematics that show wiring diagrams for several Ford tractors including the 8N. Unfortunately, it's about 2MB in size and I'm not having any luck uploading it. Drop me an email if you want it and I'll attach it in my reply. Email is bob.finley.usn@gmail.com

 

[farmer jann]

I own a 53 8N and always had to charge the battery,(even if I disconnected the battery between uses), I rewired everything, got a brand new 6 volt battery, charged it before I installed it and IT was dead the next time (about 3 days) later. I called a place that services alternators and generators and they asked me to bring in the generator for a bench test. The guy was so nice, said he would fix the thing and to come back I 2 days to pick the new polarized generator up. As I paid for the (repolarized) generator, he asked me if I realized that my tractor was a positive ground system. I looked at him, I remarked that I had changed out every battery since just the way it had been connected when I found it. I was amazed. For as long as I could remember, the 6 volt battery had been hooked up BACKWARDS! I thanked the man for the bit of info. I replaced the original voltage regulator with a new one about a year ago and it starts right up!

 

[Soundguy]

not surprisingly. arm to arm, field to field, ground to ground ( redundancy ), and bat travels off into tractor harness.

 

[tmac196]

Update:

Went to the local Agri-parts store and purchased an ammeter which the clerk had to blow the dust off as he handed it to me. Here is the package tag. The clerk couldn't tell me if voltage mattered as far as if ammeter would run off a 6v or 12v system:



Next, I performed contuinity testing on the wires between the gennie and the VR and identified the Ground, Field and Armature wires. At the VR was a fourth unmarked wire which presumedly is attached to the BAT terminal on the VR. We continuity tested this and it had continuity with the battery terminals.

The gennie was bench tested on Friday at the repair shop and pronounced "normal".

The battery had been charged for three days and tested 6 volts on the button.

After wiring connections were made we turned the ignition key and observed the ammeter needle deflect as it usually does to the left. The tractor started and ran well. The ammeter never strayed into the positive side even with engine revs. Presumedly because the battery is fully charged?

The VR never became hot.

So have I fixed my problem or am I just kidding myself and running for a few days off a fully charged battery? Any suggestions for confirmatory testing would be welcome.

tmac

 

[Soundguy]

full field the genny and seeif the ammeter strays to the right.



ie.. ground field and then bring rpms up..

 

[tmac196]

full field the genny and seeif the ammeter strays to the right.



ie.. ground field and then bring rpms up..

SG,

I assume you want me to just remove the field wire from the gennie and ground it. Leave the armature wire on which will allow the gennie to charge at full output when rotated and should, if all is correct and functional, peg the ammeter to the right ("+") side, correct?

Jes' checkin' to see if I understand you correctly.

tmac