8n genny

[sgt bull]

Okay,solve this PLEASE!
I"ve had the genny to a good local shop and it was checked. Checked good. Putting out over 7 volts.
The regulator is a new USA made one for this tractor. I momentarily jump wired the arm to bat before starting to polarize. It is wired correctly.
The amp gauge is new, from Just 8 Ns
It shows no charge. It will momentarily show discharge when cranking.
I get about 6.4 v across the battery terminals at 1/2 throttle.
If I ground the field, bypassing the regulator, there is no change in the charge rate.
The belt is new and tight enough you can"t turn the pulley by hand w/o turning the engine over.
All connections are tight, and the connectors are soldered to the wires.
Could it be that the battery is simply charged enough that no amps are showing on the ammeter?
I'm getting very annoyed at this tractor and an alternator is looking better and better all the time! ANY IDEAS? It has to be something simple.

 

[JMOR]

A little history is in order. Did this gen ever work on this tractor? Are you sure the gen and reg are a match? Meaning that there are two basic Ford generator types and of course two types of regulators. Commonly referred to as Type A and Type B (that's jargon to help keep the world of electrical things a mystery).
One type(A) sources the field internally & regulator sinks that field current and the other type (B) has an internally grounded field and the regulator sources that field current. You can't mix components & have the gen/reg set work. Now you see how much typing "A" & "B" saves.
Yes, the battery could be that fully charged, but a few starts, light on, etc. should fix that.

 

[sgt bull]

Well, I hate to admit it, but I don't recall which it was, A or B.. but I took the generator to the shop and he gave me what he said was the correct regulator for it. He's been in business for probably 30 yrs and has worked over all of my many starters, generators and alternators over the years and all have worked correctly. As far as if it ever worked, well, the tractor was "non running" when I got it, so I can't say if it worked or not.

 

[Dell (WA)]

Sarge........NO, sumptin ain't rite. You write......."I get about 6.4 v across the battery terminals at 1/2 throttle"........even at full battery charge yer genny will be puttin' about 7.4-volts into the battery terminals. 6.2-6.4 volts is nominal wetcell full charge volts. Full charge means it won't take ennymore AMPS without boiling acid out the holes. The voltage regulator actually controls the amps into the battery. The volts read is an inverse reflection of the amps. Its the LAW, Ohms Law.

My guess is you've either gott'chur wires crossed ...or... yer squarecan voltage regulator is BAD..........Dell

 

[JMOR]

If that ammeter never moves, I suspect it is no good or not wired correctly.
It ought to move with lights or some kind of load.

If you are sure you have gen ARM to reg ARM, fld to fld, and BAttery to reg BATT, then disconnect the field wire at generator and use a jumper to temporarily connect gen's Fld terminal to gnd (you said you already did, but try again....if no chg, jump from BATT neg to gen's Fld....see any chg?

If still nothing, try leaving the jumper it place & momentarily jumper from ARM to BATT, looking for chg. Do this with both of the above FLD jumper positions. Be sure & note results so you know what did what. Generators are pretty rugged, but don't leave any of these temporary jumpers in place for more than 20- 30 seconds ...just to be safe. Post back.

 

[sgt bull]

I was hoping to see your moniker in a reply! I've cked and rechecked my wiring and it all seems to conform to the diagram. I'm pretty much stumped. Wouldn't direct grounding the field bypass the regulator and give the actual max charge the gen can put out? I figure I'll pull the gen and take it back to the shop and recheck it, but I'm starting to feel pretty foolish. What would be your next step if you were facing this quandry? I've got another 8n that charges just fine, so I may first swap genny's and see if that makes a diff, and then try swapping regulators.... If THAT doesn't fix it, it MUST be a wiring screw up on my part, but its such a simple system, I just can't see how... here's what I have, looking at the wires and typing each line:
THE TRACTOR HAS NO LIGHTS.
1. wire from Arm post out rear of genny to Arm post on regulator.
2. wire from "G" post on genny to base of regulator. I ck'ed and I have a good ground from the genny to the pos. post on the battery according to my ohm meter.
3. wire from "F" on genny to "FLD" on reg.
4. Wire from "Bat" on reg to top post on terminal block
5 wire from top post on terminal block to - side of ammeter.
6. wire from top post on terminal block to key switch
7. other wire from key switch to bottom post on terminal block
8. wire from bottom post on terminal block to coil.
9. wire from + side of ammeter to starter solenoid terminal post w/ battery lead on it.
10. Wire from block side post of solenoid to starter button.
11. battery wire from solenoid to - battery post.
12. ground strap from + post to main case.

Okay, is there any thing there screwed up? I know that sometimes when you get something in your mind as being correct, its sometimes difficult to see the error...

 

[Dunk]

If you battery is fully charged it may not want to over charge it.

Try this.

Leave your switch off.

Crank it over quite a few times, stop, wait a minute, crank it over a few times, what we are trying to do is to discharge your battery some here.

After doing that 4 or 5 times, and not running the battery down past it turning good, crank it.

Then see what it does.

 

[sgt bull]

aaaaaaaaaaaaaaaaaaaaaaaaaaaaagggggggggggggggggggggghhhhhhhhhhhhhhhhha!!!!!!!!!!!!!...... TRIED IT.... no change. grrr. "I won't torch my tractor, I won't torch my tractor, I won't torch my tractor"..... there's gonna have to be a support group formed or I'M GONNA TORCH MY TRACTOR! just kidding.... frustrating, ain't it?

 

[teddy52food]

Take the generator and regulator back to the test bench & check them together. Just because the regulator is new doesn't mean it will work. Let us know what you find. OK? I think the small windings ( pull in ) in the cut out are defective.

 

[sgt bull]

take a look at my return post to Dell. It has the wiring "diagrammed" in words. Do you see anything wrong?

 

[sgt bull]

I'm going to swap a KNOWN working genny first and see if that works... the regulator is a pain to take out, so that will come next...should know in about 15 minutes if that will take care of it as I already have the good one off....

 

[sgt bull]

could a battery with a bad cell cause this? the tractor starts and runs fine, and the battery is relatively new... but new doesn't always = good.

 

[JMOR]

No, I don't see anything wrong in your verbal wiring diagram. In my earlier post those instructions would have ruled out type A/B mismatch possibilities as well as virtually eliminating thr regulator. Have you tried to "motor" the generator....as SouNdguy says, if it will motor it will charge & visa versa.

Maybe if you just use it for a week or two & the battery doesn't go dead, then you can conclude that all is well.
After all, it really isn't broken is it?

 

[Dell (WA)]

Sarge........surprizingly enuff, I can't find enny miss-stakes in yer 12-step program, iff'n yer certain yer tractor wiring matches the 12-steps.

You asked........"Wouldn't direct grounding the field bypass the regulator and give the actual max charge the gen can put out?"........YES.

I "full-field" the genny at the genny barrel studs 'cuz they're eazy to gitt-too. (genny barrel studs are FIELD and GROUND) Max output should be about 20-AMPS but yer dashboard ammmeter won't read that (unless yer battery is really dead and it ain't 'cuz you report about 6.4-volts)

"Full-fielding" should place about 7.4-volts att'chur battery posts. (I use meter leads with clippies for hands-off meter testing) while I mess-round with another clippie test-lead on the genny barrel posts. (it should be intuitively obvious yer tractor engine gottta be runnin' at about 1/2-throttle to test fer full-fielding)

Iff'n you don't gitt about 7-1/2 volts "full-fielded," my guess is yer squarecan voltage regulator is BAD inside. Won't be the first time a voltage regulator has been bad rite outta the box.......Dell

 

[Bob]

Is the voltage regulator properly grounded, or is it mounted to either nice new paint, or crappy old rust?

The regulator HAS to be grounded, or it's field relay can't ground the generator's "FIELD" to get the charging process started, nor can it's cutout relay pull in, without the unit "seeing" a good ground.

BEFORE going to all the trouble of swapping parts, check the charging voltage at the generator's output stud ("ARM").

The cutout WILL NOT initially CLOSE unless it's getting 7.0 to 8.5 Volts from the generator.

Often, folks say "the generator is WORKING, it's putting out about 7 Volts". WELL, that is the bare minimum threshhold of the voltage range at which the cutout is "spec'ed" to close, and the cutout is even "in spec" if it initially closes @ 8.5 Volts, so the generator's output HAS to be in that range to get the cutout's attention, so it closes, and connects the generator to the battery, so charging can occur.

What is the generator's output voltage at 1/2 throttle? Then, full-field the generator, and note it's output voltage.

IF the generator is outputting enough voltage (7.0 to 8.5 Volts) AND the voltage is getting to the "GEN" terminal on the voltage regulator AND the regulator is properly grounded, it's "cutout rely" SHOULD be closed, and the generator voltage should be "seen" at the output (BATT) terminal of the regulator.

WHAT is the voltage at the "GEN" and "BATT" terminals on the regulator @ 1/2 throttle?