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The bestest way and the easiest way to get this system to work is remove the Generator, bring it to a good replicable rebuilder and have him mate the proper VR to the Gennie. What I do in my shop is if the Gennie still has the tag on it, I mate a VR to the Generator part number. I then set the two up on the 881 machine and dial them in together. If no tag, I run/load test the unit to see if there is any output and what it's max. output is. Then I mate the proper VR to the unit and run/load test them together.
As for Batteries, Steve is correct. Six volt Batteries have 3 cells. (caps) Twelve volt Batteries have 6 cells. (caps) Easy to remember. If you plan on keeping it 6 volt and you're not using the 3 position switch to control the ground, (charging) mate the proper VR to the Gennie as I mentioned. Have a rebuilder do it for you. It takes all the guess work out.Another thing to keep in mind that's always overlooked. Make sure the fan belt you are using is new or in very good shape. Old dry rotted belts slip causing a no charge issue.... HTH
Steve@B&B
Edited by Steve in NJ - 10 Jul 2024 at 10:04am
39'RC, 43'WC, 48'B, 49'G, 50'WF, 65 Big 10, 67'B-110, 75'716H, 2-620's, & a Motorhead wife
I took a knock off delco alternator to get it repaired years ago and the guy said they make a 1000 different ones of these, and we can fix 999 of them. I was always impressed how he left himself a way out lol.
Dale, here is a drawing of the ORIGINAL 6 v system with POSITIVE GROUND on your tractor... Note that the "ARMATURE" terminal is the HOT terminal on the generator... that would go to the amp meter then NEGATIVE BATTERY terminal on a POSITIVE GROUND system..
If you have NEGATIVE GROUND, then the HOT TERMINAL is the POSITIVE... That is one problem when discussing 6V systems.....
The drawing is also correct that the "A" terminal is toward the OUTSIDE of the tractor and the "F" terminal ( ground to light switch) is toward the ENGINE BLOCK.-- asssuming you had the ORIGINAL GENNY... which you probably do NOT ??
When you get your "REGULATOR", you need to determine how the BATTERY is grounded .. and that will be the "F" terminal.... the "A" to your "G" terminal will be the HOT terminal on the battery..
Dale, i was assuming you had the ORIGINAL generator... which does not seem to be the case... The BIGGER of the two terminals is usually the ARMATURE and the SMALLER terminal is the FIELD ( ground).... it would appear your "A" terminal is the one closest to the engine block... from your PHOTO ??
i think this is what is confusing us on "the wires are switched"...
The Allis B is now charging at about -5 amps, using an old Allis CA generator. Battery tests a 7.96 volts (6.52 volts when not running) and 7.35 volts at the generator posts.
Hopefully the negative amp reading doesn’t mean it’s sucking out the charge. I did try to reverse the ARM/FLD wiring on the generator, but the ammeter read zero.
I installed the old Allis CA 6 volt generator that I happened to rediscover (I had taken it off in 1998 not knowing if it worked or not). I was searching for a pulley for an old Allis B generator that I just purchased from a neighbor (he didn’t know if his salvaged generator worked or not). Because I couldn’t remove the pulley from my old Allis CA generator, I just decided to see if it would work on my Allis B.
I found a never used cutout relay (in original box) in my tractor stuff. Wrapper shows “R11-F, 6 volt cutout, 617837-3”. It has “2727” stamped on its metal case. Wiring was: GEN cutout terminal to generator ARM (bottom) post, Generator FLD (top post) grounded to small bolt on generator, I used 16 gauge wire for both.
I had decided to find a replacement generator, since I couldn’t get the current one to run by jumping it directly to the battery (with the belt removed). Also, I didn’t want to run the risk of burning up the new 6 volt regulator I bought from Steiner.
The now unused Steiner regulator is part #ABC152, which is listed as for being for early model Allis D10, D12, etc. Steiner identified what part I needed from the fact that my old Allis B generator has only two brushes, rather than three. This new regulator has four terminals - terminal “L” (lights) would have been unused in my installation.
At last resort, I was going to make the 3 hour road trip to the “local” generator shop. Thankfully I avoided this. (maybe)
So now I have more excess parts if anyone is interested in them: (a) old D10 6 volt generator that doesn’t seem to work (maybe it needs new brushes?). (b) old Allis B 6 volt generator - don’t know if it works or not. It’s missing pulley, cutout, and wiring. (c) new Steiner #ABC152 6 volt with 4 terminals, still in box - never wired and never installed. (d) old Echlin [NAPA] 3 terminal regulator. Based on info from jaybmiller & Steve, it’s a 12 volt Echlin 27-31 regulator. Don’t know if it works or not.
nice to hear someone's winning today (don't ask..)
as for the amps...
disconnect battery THEN check the ammeter wiring. Odds are it was reversed when someone went -ve ground (the standard today ) from the +ve gnd wiring when the beastie was 'factory fresh'.
3 D-14s,A-C forklift, B-112 Kubota BX23S lil' TOOT( The Other Orange Tractor)
Never burn your bridges, unless you can walk on water
yea... your eventually going to need a LIGHT SWITCH RESISTOR.. or a stand alone resistor to cut the charge down... When you GROUND the "F" terminal, you should get 8 amps on an ACURATE GAUGE.... (You might have 5 amps, you might have a little MORE)... Possible to overcharge the battery... Resistor cuts that charge to 2-3 amps constant..
1. jaybmiller and Alberta Phil: I switched the ammeter wires (single wire on one post and two wires on the other post) and am now getting about +10 AMP reading at low charge (but high RPM). Pulling light switch out to high charge did not move the needle. I guess a negative AMP reading did mean it was actually discharging. Thanks for the advice, but now have to figure out the overcharging issue (see below).
2. Les Kerf: I reviewed the FLD wiring diagrams again and added a 16 gauge wire from the generator FLD post to the resistor wire post on the light switch. I'm now getting 8.42 volts on the battery and 9.80 volts on the generator posts. So I think it's now overcharging. Thanks for the heads up.
3. Steve: As per the above, the system now appears to be overcharging. - too many AMPS and too many VOLTS. I also did note that the operators manual stated it should run at about 3 AMPS, but I don't know if this is at Hi or Low rpm. The light switch does have a resistor. I attached the new FLD wire from generator to the resistor. I attached the wire to the resistor wire end that was easiest to access - could that be the wrong end? My resistor wire design is a little different than what is shown in the diagram. Lastly, I did FLASH the generator and grounded the instrument panel box, which helped a little (see below).
Any suggestions as next steps? Maybe (a) defective light switch, (b) defective resistor, (c) wiring to wrong resistor wire end, (d) wrong cutout relay model, (e) remove the new wiring from FLD to light switch resistor, (f) time to take it to a generator shop???? Will appreciate your and other's thoughts on this overcharge problem.
THe CUT OUT is ON- OFF... has nothing to do with charge rate.. Just opens the circuit when engine not running... Generator voltage on a 6 volt system will put out about 12 volts... It is the BATTERY that sets the voltage charge.. Kind of like a HEAT SINK.. Remove the battery wire and the generator will put out 12v... a 12v generator will put out 20 v if not REGULATED by the battery...The CHARGE RATE or AMPS is controlled by "how good is the ground wire on the F terminal"... If you got a GREAT ground, then you get 8 amps... if you have a restricted ground ( thru the resistor) then you should get about 3 amps... If you turn on the lights they will pull 3-4 amps so that is why the resistor is not in the circuit when the lights are on.
If you GROUND the F terminal the amp gauge should say 8.
If you connect the RESISITOR to the F wire and ground the other side, it should say 3 amps.
IF you get a LOT MORE VOLTS or AMPS out of the generator, then the generator probably need adjusted / cleaned/ etc.. internally.
the sheetmetal cover around the back 2 inches of your generator would lead you to believe it is an older 6v generator.. You THINK it came off a CA...
You can take that cover off and LOOK at the brushes and springs pushing on the center shaft. See that everything looks GOOD... You MIGHT have a 3rd brush around the shaft that has a screw and slot that allows it to loosen and ROTATE back and forth.. That ADJUSTMENT is to set the amp/ voltage charge on a simple generator that does not use a voltage regulator....... if you see rust , clud, broken or bent spring, worn brushes, etc, then you need someone to do internal work.
2. Les Kerf: I reviewed the FLD wiring diagrams again and added a 16 gauge wire from the generator FLD post to the resistor wire post on the light switch. I'm now getting 8.42 volts on the battery and 9.80 volts on the generator posts...[/QUOTE wrote:
You need to remove the wire connecting the field to ground at generator, it is full-fielding the generator, thereby driving it to maximum output (overcharging).
Less Kerf: I removed the FLD wire to case and got better readings the first time, especially the VOLTS on generator. I tested a second time and got some crazy inconsistent readings. See chart below. Tomorrow I'll put new batteries in the voltmeter, RE-Flash the generator and re-test.
Interesting to note that when I pull the light switch all the way out, I never get an increase in charging rate. Could this indicate a faulty switch?
Steve: I will try to adjust the 3rd brush as you suggested. What is an acceptable target for battery VOLTS at Hi RPM? I had read once that a battery should test in 7-8 volt range while at rest. Anything in 6-7 volt range indicates a problem. But have no clue what is target for battery running at Hi RPM. Also not sure about the 3 AMP target at Hi or Low RPM.
I did not realize when you ran the "F" wire to the resistor, you left a second wire from the "F" terminal to ground. ( look at the print above again... only 1 wire on F).... Resistor will do nothing if you have the "F" grounded.. You will get FULL CHARGE.. If you removed the ground and ran the wire to the resistor, and then appears you get random numbers, that means the Resistor is not working, or is not grounded on one side.....I would get that fixed before trying to adjust the 3rd brush.. The resistor has to work to get the LOW AMP CHARGE of 3 amps.... Most of the NUMBERS we discuss will be at hi idle, operating rpm .... you might not get much at idle speed.
If you have a spare resistor... wire it to the "F" terminal of the generator and touch the other end of resistor to the case ( GROUND)... That would bypass your wire and switch and be a good test... For voltage, you would like to be right around 7 v... 6.9 to 7.1 or so.... more that 7.4 is too much and will cook the battery... All values are for HI IDLE.. Resistor should also get you down to the 3-4 amp charge range.. Constant charge at 8-9 amps is too much for the battery.
Does your tractor currently have a light switch with a resistor or just an on/off or pull type switch without one? As others have said to use a cut-out on the generator your field current through the generator is controlled by the resistor in an original style switch. when your tractor had a regulator on it as in your first post the switch could have been changed or the resistor was bypassed.
RE-FLASHED the generator (Fifth Read): still zero AMPS and lower VOLTS
Steve: couldn’t locate a spare resistor to run a test. But, I’m getting zero AMP readings now (after removing ground wire), so unsure if a resistor test would help find the problem. Would the resistor test only help if it had a HIGH AMP reading? Thanks for the target AMP and VOLT information
Riprock: Yes, my light switch has a resistor. It’s similar to the wiring diagram shown on page 18 of my CA operators manual
Now (after removing the ground wire) I’m getting no AMP readings - positive or negative
There are no change in AMP readings (always zero) when I run through each of the light switch charging positions
Installed a Headlamp to see if I could get a negative AMP reading. Still all zeros.
The Headlamp stayed ON when: the ignition key was on, and when engine running (high RPM) and using all three light switch charging positions
Could the light switch be faulty?
Could the instrument panel be wired wrong? I realize now that this Allis B might have previously been set up for 12 volts negative ground. It had 12 volt solenoid, coil, voltage regulator, D10 type generator(?), ammeter wiring for negative ground. I didn’t take a close look at the old dead battery before buying a new 6 volt.
Switching the wires on the ammeter (as suggested by jaybmiller & Alberta Phil) gave me a nice AMP overcharge (before removing the ground wire).
As per the wiring diagram, the light switch doesn’t seem to have a wiring alternative. But maybe I wired the generator’s FLD wire to wrong end of the resistor? I guess the fuse must be good since the lights work(?)
Should I rewire the FLD post to ground and see if it doesn’t overcharge too much?
I appreciate everyone’s comments, advice and patience.
If you GROUND the "F" terminal on the generator you will get 8 amps...
IF you jumper the "F" terminal to the light switch resistor ( and it is grounded on the OTHER END), you will get 3 amps.
If you get the 8 amps with the ground wire, but not the 3 amsp with the resistor / wire... then the resistor is bad... the resistor is not grounded.. the light switch is bad.. the light switch is not grounded... or the light switch BOX is not grounded.... basiclly you have NO GROUND when your using the resistor..
Thats why i said try an extra resistor... another option is to run the wire to the RESISTOR on the light switch and JUMPER the other side of the resistor to a GOOD GROUND... if that works, you know you dont have a good ground on the light switch ( or your using the wrong terminals)... if it does NOT WORK.. then your resistor is junk.
A GOOD GROUND test is to take a 2 ft long jumper and connect to the BATTERY + terminal, then touch the LIGHT SWITCH CASE.... and then the LIIGHT SWITCH RESISTOR terminal.... something is BAD at that area.
your switch may look something like this... the SWITCH CASE has to have a GOOD GROUND for everything to work.. If you have paint or rubber bushing on it.. could be a problem.
Ran through some of Steve’s suggestions and found that after jumping Resistor to Positive Battery Ground (with headlamp ON) the reading is 5 AMPS and 8.11 volts (both too high). Using the light switch’s high charging position did not result in higher AMP reading. The headlamp remained ON under all three light switch positions, which is another problem.
Ran the test again with the headlamp disconnected. Low charge was at zero AMPS and high charge was at 5 AMPS and 8.29 volts.
I considered buying a new Light Switch, but it appears these are no longer available for purchase. I tried to compare my instrument box wiring to the published wiring diagram and found three potential issues:
Wiring diagram shows wiring from Ammeter direct to the Light Switch Fuse. Mine has wiring from Ammeter to Ignition Switch, then wire from Ignition Switch to Light Switch Fuse. Is this a potential problem or is this an acceptable wiring technique?
Wiring diagram shows each of the following having a separate ground: Ignition Switch, Light Switch Resistor, FLD post on generator, and headlamps. My Ignition Switch is not separately grounded, nor is there any ground terminal that could be used for that purpose. Is this a potential problem, or is it sufficient that the Instrument Panel Box is properly grounded (If the Box is grounded, don’t all the attached switches become grounded)?
The wiring diagram shows both the Resistor and the FLD post (on generator) as being separately grounded. Should I ground the FLD post again - or does this negate the effect of the Resistor as previously discussed?
found that after jumping Resistor to Positive Battery Ground (with headlamp ON) the reading is 5 AMPS and 8.11 volts..
IF you can verify that the "F" terminal wire to the BOX is not ground somewhere else, then YES... that is too much amps and volts for the resistor circuit.. If you take the JUMPER off the resistor, then the amps drop to ZERO because there is NO GROUND CIRCUIT.. Right ?
There are aftermarket switchs, but some do not FIT in the box very well.. You can have your switch Professional REBUILT by Steve @ B&B if your interested...
1 . This tractor had no "ignition switch" from the factory. If you have one, then yes, the power can run thru the switch before going to the light switch.
2. The PRINT gives the impression that there are several ground wires. There are not.. The STARTER is grounded thru the case to the FRAME... the Generator is grounded thru the case to the Engine / frame.... the light switch is ground thru its case to the BOX... the BOX is grounded to the tractor FRAME thru the mounting bolts... NO WIRES except the GROUND on the battery.. the ENGINE / FRAME is the GROUND CIRCUIT.
3. No, the generator "F" terminal is not grounded with a wire at the generator. The WIRE goes to the light switch and is GROUNDED when the lights are on and runs thru the RESISTOR to GROUND when the lights are off..
It would appear you still have several problems with the light switch / box / wires.. I would verify that you have NO AMP CHARGE when you pull the ground off the RESISTOR and then 5 amps when you GROUND THE RESISTOR... If that is the case, then your generator needs Repaired or Adjusted ( brush) inside...
Dale, you need to temporarily forget about the light switch. It is just complicating the problem.. All you need in the LIGHT BOX , the RESISTOR , the WIRE FROM "F" and a good ground....
When you run the wire to the resistor , you get 3 amps.. when you run straight to ground you get 8 amps.. That will verify your generator is working correctly.. Dont care what the lights are doing.. worry about that later............. this is a simple version.... i might be temped to take the POWER wire off the light switch for now, just to verify that it is not adding to the problem.
What if your "F" wire is ALWAYS GROUNDED at the switch due to wrong terminal or bad switch ?????
It looks like on test 6-7-9 that you are getting 5 amps when you ground the resistor and put the "F" wire to the other side of the resistor.... ( dont care what the light is doing or what happens at low idle).... Now take the F wire and GROUND it to the battery.. You get 8 amps ??? or ?
After running through some more testing (FLASHED after each wiring change), at a point where I can live with the current results of about 4 AMPS in all three light switch positions (without headlamps). To fix all the problems, think I would need a replacement light switch and/or an adjustment to the genny’s 3rd brush.
These tests were made with the front cover of the Instrument Panel Box removed. I had to separately ground the box to positive battery ground to get any AMP readings. The Instrument Panel Box is full - it contains: ammeter, starter solenoid button, ignition switch, and light switch.
When testing with headlamp wired, only one of the bulbs worked (one appears to be burnt out). I used the light to test for amperage discharge - but none was noted. Light remained ON for all tests, under all 3 LS charging positions, both when key is ON and when engine is running (thinking LS is bad).
FLD post wire connected to near end of resistor:
No lights wired: 4/4/4 AMPS for the three LS positions
Light wired: 4/4/4 AMPS for the three LS positions
FLD post wire connected to far end of resistor:
No lights wired: 0/4/4 AMPS for the three LS positions
Light wired: 0/4/4 AMPS for the three LS positions
FLD post to GRD wire (removed FLD to resistor wire):
No lights wired: 4/4/4 AMPS for the three LS positions
Light wired (early test): 4/4/4 AMPS for the three LS positions
Light wired (later test): 0/0//0 AMPS for the three LS positions (???)
Some old John Nordhoff questions I found:
With lights on, do both “out” wires on the LS show VOLTAGE: NO, only one wire shows voltage (thinking LS is bad)
With lights on, does the AMP reading show discharge: NO
Does Ammeter read HOT on both terminals: YES
Does BAT cutout terminal read HOT: YES
I appreciate all the helpful comments and suggestions, especially the one pointing out the need for a switch in the ammeter wire terminals.
a few days ago you had 8 amps... not sure how you got to 4 today ?... If you take the "F" terminal wire and go to the resistor, you get 4 amps... if you ground the "F" wire you still get 4 amps ? ....... That means your wire is always grounded somewhere.. you should have a LOWER reading when going thru the resistor... I think your wire from "F" might be touching ground somewhere... and your switch is definitely bad.
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