841 Genny Question

[graham_in_NJ]

I did research thru the archives....but still have a question...

I have no charging. The regulator is not original so is probably junk, but before I start throwing more parts at this tractor, I need to make sure the generator is ok.

The generator is on the machine and the belt disconnected. The only wire on the generator is the ground wire (which i measured to be zero ohms to the pos term of the battery. When I connected the hot of the battery (neg) to the armature (big stud on the back), there was no spin. When I added the field to the arm with hot, I got spin. Thought it should spin with just hot to the arm, and then faster by adding in the field. Might be mis-reading the older posts.

I measured the impedance:

Arm-ground 1.4 ohm
Fld-ground 2.5 ohm
Field-Arm 3.4 ohm

Thoughts?
As always, thanks for the advice

 

[JMOR]

(quoted from post at 17:13:06 04/07/20) I did research thru the archives....but still have a question...

I have no charging. The regulator is not original so is probably junk, but before I start throwing more parts at this tractor, I need to make sure the generator is ok.

The generator is on the machine and the belt disconnected. The only wire on the generator is the ground wire (which i measured to be zero ohms to the pos term of the battery. When I connected the hot of the battery (neg) to the armature (big stud on the back), there was no spin. When I added the field to the arm with hot, I got spin. Thought it should spin with just hot to the arm, and then faster by adding in the field. Might be mis-reading the older posts.

I measured the impedance:

Arm-ground 1.4 ohm
Fld-ground 2.5 ohm
Field-Arm 3.4 ohm

Thoughts?
As always, thanks for the advice

ounds like it is OK... Sometimes they are so dirty /old grease/weat that they won't 'motor' without some help or with addition of field current. Generally, when all is in very good condition, if you start with field current & then remove field they will increase speed rather than slow down. You can momentarily check for charging by connecting Field to Arm and then Arm to battery while running. That is same connections that VR is making when asking for full output. Don't run long though as there is no current regulation.

 

[graham_in_NJ]

I only get spin with field. If I remove field with arm still hot it stops. That still acceptable, accounting for wear, or should I pull it apart and check brushes? I would assume that the armature is ok. The generator spins pretty freely when not energized, so I'm assuming bushings are fair....

 

[JMOR]

(quoted from post at 17:47:07 04/07/20) I only get spin with field. If I remove field with arm still hot it stops. That still acceptable, accounting for wear, or should I pull it apart and check brushes? I would assume that the armature is ok. The generator spins pretty freely when not energized, so I'm assuming bushings are fair....

ersonally, I would wire as said and see if charges..

 

[graham_in_NJ]

Thanks JMOR on the spin confirmation. Problem found. I opened up the regulator. Looked new. Turns out that the relay coil that the battery is connected to was open. When I manually closed the relay I saw voltage at the Armature connection which wasn't present prior. That's why no voltage appeared at the battery when I full-fielded the generator. I do note that the generator puts out almost 36 volts unloaded at full field.

So even though the regulator looked perfect, it was not.

Does anyone have any recommendations on where to get a regulator? Read a lot in the archives that the imports are.....just junk. I guess I may not have much in the way of choice, but I thought I'd ask for opinions.....

 

[JMOR]

(quoted from post at 19:04:54 04/07/20) Thanks JMOR on the spin confirmation. Problem found. I opened up the regulator. Looked new. Turns out that the relay coil that the battery is connected to was open. When I manually closed the relay I saw voltage at the Armature connection which wasn't present prior. That's why no voltage appeared at the battery when I full-fielded the generator. I do note that the generator puts out almost 36 volts unloaded at full field.

So even though the regulator looked perfect, it was not.

Does anyone have any recommendations on where to get a regulator? Read a lot in the archives that the imports are.....just junk. I guess I may not have much in the way of choice, but I thought I'd ask for opinions.....

'll let someone else take that, because I have no idea where/who you can count on for those.

 

[Tim PloughNman Daley]

Something isn't kosher with your genny. Are you running the OEM 6V/POS GRN setup? If I understand you correctly, you genny has only a single wire connection? If so, it's the wrong one for starters. A 1-Wire generator would be what was used on the 9N-10000-B (after s/n 12500) & C units and the 2N-10000 unit, both 11.5 AMPS with the 'A' Circuit designs. Ford changed to a 3-Wire/3-Brush, 11.5-AMP,
'A' Circuit design unit with the 8N model and a VR. Since early 1950, Ford then changed to the 3-Wire/2-Brush 20 AMP, 'B' Circuit Design unit and these were used all thru the Hundred Series models. The 8N and up all used a Voltage Regulator as well. The VR has three terminals - ARM BAT and FLD. Once you verify the entire wiring is correct and you have all the correct components, you polarize the generator which is easily done via the VR. NOTE the B-Circuit Design is polarized different than the 'A' Circuit and if not done correctly will smoke the VR. I don't think you have a bad VR. The 8N/20 AMP module shows the Field Resistance should be 3.2 OHMS. Your trusty starter/alternator/generator shop can bench test your battery, starter, genny, alternator, VR, and more. Get a copy of the CLYMER/I&T FO-20 Manual and verify wiring is all correct. Meantime, here's a page from the OEM Ford 600/800 Owner's manual:

FORD 600 & 800 TRACTOR ELECTRICAL DIAGRAM:

FORD TRACTOR GENERATOR CIRCUIT DESGNS - POLARIZING via THE VOLTAGE REGULATOR:

Tim Daley(MI)