Farmall SC charging issues.

tfringo

Member
Help me help me help me!

First off, Hello again. Last time I was here, I was fixing a broke axle on my SC and replaced a bull gear. All went well with that.

So, I finally got around to working on my charging system (was always in a discharge state). Only way it would ever charge is if I tapped on the regulator box, then it would charge for a while and stop. Other wise, it would discharge until it wouldn't have enough strength to turn over.

It is original 6 volt positive ground. I popped off the generator which is the correct one for the tractor based on the parts manual and the number on the identification tag. So, good there. It is a fixed three brush generator. I removed the generator and put new field coils in it, cleaned the armature, new brushes and bearings. Had it tested and it put out 6 amps just fine under load.

I ordered a new regulator. And, I polarized the system by following the owners manual.

After all this, it charged for a good while when I first started it. Was pushing about 3-4 amps. Then I looked down and noticed it wasn't charging.... showing a slight discharge. It has stayed like this ever since and I have given it ample opportunity to kick on. It just went until it drained the battery.

Why is this happening to me. I have repaired this system several times (rebuilt the generator or replaced the alternator). Best I get is I have to tap on the regulator to get it to charge and then it will charge for a very short time.

Battery takes a charge on my trinckle charger.

What could be causing this situation? Any suggestions. 1) I plan on disconnecting a battery lead and checking for a current draw.

Is it possible I have a small short somewhere that would upset the regulators ability to sense? Coil? or Starter?

Let me know. Thanks!
 
Use an OHM meter to make sure all systems are grounded. Where did you get the reg as it sounds like the culprit. You can use a jumper from feild teminal to ground and see if that will show charge. If that does show charge that will prove the reg is not working. Make sure the reg is for that gens Delco #.
 
Six amps maximum output sounds awfully low to me. How far is the moveable brush from the output brush. Moving it closer should make it charge more. Like stated above it is probably the regulator.
 
Thanks for the advice. I will try to keep you posted on my progress.

On this generator, it appears the 3rd brush is fixed, NOT adjustable. I will piddle with it today and let you know what I find out. Been a great tractor but the charging system has always been an issue.

Thanks, Terry





(quoted from post at 05:19:14 06/15/17) Six amps maximum output sounds awfully low to me. How far is the moveable brush from the output brush. Moving it closer should make it charge more. Like stated above it is probably the regulator.
 
THe following should help, it is copied from another post on YT and is complete.
TROUBLESHOOTING CHARGING SYSTEMS By John T retired electrical Engineer and YT GURU.
ARE YOU SURE THE AMMETER IS WIRED CORRECT AND WORKS????? If you turn the lights or ignition on (if coil ignition not a mag) when she?s not running, the ammeter should
swing over to the - discharge direction, does yours??? Are BOTH the ammeter terminals reading hot battery voltage?? They MUST !!!!!!! There?s but one wire on the
ammeters Supply (from battery/starter) terminal while its other Load terminal wires to the BAT terminal on a Cutout relay or VR PLUS wires to feed loads like lights or
ignition, UNLESS where a 4 terminal VR is used, and if so lights n ignition are fed from the LOAD terminal on the VR.

To Polarize the Generator, first temporarily dead ground the Gens Field post to case/frame, then momentarily flash jump a wire from the Cutout Relay or VR's "BAT"
terminal over to its GEN/ ARM) terminal and you ought to get a small spark. Same things accomplished by momentarily flash jumping a hot wire (BAT terminal on Cutout
Relay or VR or starter post etc) direct to the Gens ARM post to get the spark.

TROUBLESHOOTING A CHARGING PROBLEM IN CLASS A DELCO TYPE SYSTEMS

1) For a good working Gen to get to and charge the battery, it has to have a path usually from the Gens ARM post,,,,,,,,,,To and through the Cutout Relay (between its
GEN and BAT terminals, regardless if on a VR or Relay),,,,,,,,,Up to the Load (NOT to battery) side of the Ammeter,,,,,,,,,To and through the Ammeter,,,,,,,,,,From BAT
side of Ammeter to ungrounded battery terminal, often via the starter lug post. Is yours wired that way or equivalent ??? The ammeter should read hot battery voltage
on BOTH terminals, does yours??? Even if an ammeter were stuck (but still continuous) as RPM increases the battery voltage should rise from 12.6 to near 14 volts
and/or the lights glow brighter (half that on 6 volt systems). Have you tried that in case the ammeter isn?t working right?????

2) If the above is so, the BAT terminal on the VR or Cutout Relay MUST ALWAYS READ HOT BATTERY VOLTAGE. Does yours??? If not, the Gen cant get to and charge the
battery.

3) The Gen to VR (if it has one) wiring is as follows:

BAT on VR to ammeters load (NOT battery) side

ARM (or GEN) on VR to Gens Armature post.

FLD on VR to Gens Field post.

(L) Load (if you have a 4 wire VR) up to BAT supply input terminal on switch to feed loads like lights and ignition.

WIRING ON CUTOUT RELAYS: They wire BAT side to ammeters Load terminal,,,,,,GEN side to gens Armature post. On cutout relay systems, the Gens Field post is wired to the
light switch where it gets a dead ground for high charge or a resistive ground for low charge. Therefore, there must be a good connection from the Gens Field post up
to the switch PLUS the switch is good and it?s well grounded !!!!!!!!

4. THE GEN AND VR OR CUTOUT RELAY MUST BE WELL GROUNDED AND THE BELT GOOD N TIGHT. If any doubt, run a ground wire from the grounded battery post or clean solid frame
member direct to the Gen and see what happens????????????????????????????

NOW, if the Gen and VR are grounded,,,,,all is wired correct,,,,,,,,BAT terminal on VR or Cutout Relay is HOT,,,,,,,,Belt is tight,,,,,,,,,Ammeter is good n continuous
n works but she wont charge, have you had the batteries tested lately????? Is there electrolyte above all the plates and no cells have a gray or milky appearance??????
A bad battery may not accept a charge you know!!!!!!!! If the battery checks okay, proceed below to see if its a Gen or VR problem (AFTER you have insured the wiring
per the above)

TO DETERMINE IF ITS A GEN OR VR OR CUTOUT RELAY PROBLEM

5. a) VOLTAGE REGULATOR SYSTEM: With the tractor running, temporarily ground the Gens Field post to case. If she charges then but NOT otherwise, the VR may be bad, or
a wires missing from VR's Field post to the Field terminal on the VR, or the VR isn?t well grounded.

b) IF IT?S A CUTOUT RELAY SYSTEM and she charges only if you dead ground the Field but NOT otherwise, its either a bad switch or the switch isn?t well grounded or else
the wires bad or open from the Gens Field post up to the switch. INSURE THAT GOOD SWITCH GROUND AND WIRING

6. If she still don?t charge, leave the Field grounded and jump a wire across from the VR or Cutout Relays BAT terminal over to its GEN terminal (jump by passes the
cutout relay) and see if she charges. If then but not otherwise, a VR's cutout relay isn?t working correct (maybe points burned/carboned) or a Cutout Relays NOT
working or not wired correct.

7. With the 2 steps above, you have basically by passed the VR or Cutout relays functions, so if she still don?t charge, you're left with a bad battery or wiring or
the Gen itself.

8. MOTOR TEST. You can Motor test the Gen. If its grounded and you remove the belt and apply hot battery voltage direct to its ARM Post and have the Field Post dead
grounded to frame, it should motor n run well (Armature n Brushes and Commutator likely okay). Then, if you next remove the Fields ground and it speeds up some, the
Fields probably good. If it passes both those tests, it should charge, and if not, it may be a wiring or battery or grounding problem. The hot battery voltage may be
taken off the VR's BAT terminal or the starter post or the battery itself for this test.

9. Typical Gen problems may be the brushes are worn down or the hold down spring assemblies are stuck/corroded/dirty and arent pushing the brushes tight down against
the commutator. Check those things out. Worse may be bad fields or armature etc. Air and WD 40 etc can clean and free them, the hold downs must be free n snap and hold
the brushes DOWN TIGHT and they cant be worn down too low.

SUMMARY: Check the wiring,,,,,the grounds,,,,,,insure BAT on VR or Relay is hot,,,,,,,check battery (maybe load tested and Specific Gravity checked),,,,,,,,,good tight
belt,,,,,,,insure ammeter is continuous (BOTH sides HOT),,,,,,see if battery voltage rises above 12.6 (half that for 6 volt system) and/or light glow
brighter,,,,,,,,,do the Field and cutout relay VR by pass checks,,,,,,,,insure the Gens brushes arent worn down and the hold down springs are free n clean and push the
brushes down tight,,,,,,,,,,,check the connections,,,,,,,,,try the Gen Motor Test to see if its good.

You may just have a bad battery or bad ground or connection if the Gen and VR or relay are okay. Good Luck n God Bless, let us all know.

John T Nordhoff in Indiana, retired Electrical Engineer
 
Thanks! I should be a Guru too if I can get through all that. What bothers me most is that it works for a while then stops. It is like it fails to sense. I can tap on the regulator and it will start to charge for a while in the 3 amp range. But it will only do that for a while. Naughty naughty tractor. Thanks again. Terry



(quoted from post at 08:44:00 06/15/17) THe following should help, it is copied from another post on YT and is complete.
TROUBLESHOOTING CHARGING SYSTEMS By John T retired electrical Engineer and YT GURU.
ARE YOU SURE THE AMMETER IS WIRED CORRECT AND WORKS????? If you turn the lights or ignition on (if coil ignition not a mag) when she?s not running, the ammeter should
swing over to the - discharge direction, does yours??? Are BOTH the ammeter terminals reading hot battery voltage?? They MUST !!!!!!! There?s but one wire on the
ammeters Supply (from battery/starter) terminal while its other Load terminal wires to the BAT terminal on a Cutout relay or VR PLUS wires to feed loads like lights or
ignition, UNLESS where a 4 terminal VR is used, and if so lights n ignition are fed from the LOAD terminal on the VR.

To Polarize the Generator, first temporarily dead ground the Gens Field post to case/frame, then momentarily flash jump a wire from the Cutout Relay or VR's "BAT"
terminal over to its GEN/ ARM) terminal and you ought to get a small spark. Same things accomplished by momentarily flash jumping a hot wire (BAT terminal on Cutout
Relay or VR or starter post etc) direct to the Gens ARM post to get the spark.

TROUBLESHOOTING A CHARGING PROBLEM IN CLASS A DELCO TYPE SYSTEMS

1) For a good working Gen to get to and charge the battery, it has to have a path usually from the Gens ARM post,,,,,,,,,,To and through the Cutout Relay (between its
GEN and BAT terminals, regardless if on a VR or Relay),,,,,,,,,Up to the Load (NOT to battery) side of the Ammeter,,,,,,,,,To and through the Ammeter,,,,,,,,,,From BAT
side of Ammeter to ungrounded battery terminal, often via the starter lug post. Is yours wired that way or equivalent ??? The ammeter should read hot battery voltage
on BOTH terminals, does yours??? Even if an ammeter were stuck (but still continuous) as RPM increases the battery voltage should rise from 12.6 to near 14 volts
and/or the lights glow brighter (half that on 6 volt systems). Have you tried that in case the ammeter isn?t working right?????

2) If the above is so, the BAT terminal on the VR or Cutout Relay MUST ALWAYS READ HOT BATTERY VOLTAGE. Does yours??? If not, the Gen cant get to and charge the
battery.

3) The Gen to VR (if it has one) wiring is as follows:

BAT on VR to ammeters load (NOT battery) side

ARM (or GEN) on VR to Gens Armature post.

FLD on VR to Gens Field post.

(L) Load (if you have a 4 wire VR) up to BAT supply input terminal on switch to feed loads like lights and ignition.

WIRING ON CUTOUT RELAYS: They wire BAT side to ammeters Load terminal,,,,,,GEN side to gens Armature post. On cutout relay systems, the Gens Field post is wired to the
light switch where it gets a dead ground for high charge or a resistive ground for low charge. Therefore, there must be a good connection from the Gens Field post up
to the switch PLUS the switch is good and it?s well grounded !!!!!!!!

4. THE GEN AND VR OR CUTOUT RELAY MUST BE WELL GROUNDED AND THE BELT GOOD N TIGHT. If any doubt, run a ground wire from the grounded battery post or clean solid frame
member direct to the Gen and see what happens????????????????????????????

NOW, if the Gen and VR are grounded,,,,,all is wired correct,,,,,,,,BAT terminal on VR or Cutout Relay is HOT,,,,,,,,Belt is tight,,,,,,,,,Ammeter is good n continuous
n works but she wont charge, have you had the batteries tested lately????? Is there electrolyte above all the plates and no cells have a gray or milky appearance??????
A bad battery may not accept a charge you know!!!!!!!! If the battery checks okay, proceed below to see if its a Gen or VR problem (AFTER you have insured the wiring
per the above)

TO DETERMINE IF ITS A GEN OR VR OR CUTOUT RELAY PROBLEM

5. a) VOLTAGE REGULATOR SYSTEM: With the tractor running, temporarily ground the Gens Field post to case. If she charges then but NOT otherwise, the VR may be bad, or
a wires missing from VR's Field post to the Field terminal on the VR, or the VR isn?t well grounded.

b) IF IT?S A CUTOUT RELAY SYSTEM and she charges only if you dead ground the Field but NOT otherwise, its either a bad switch or the switch isn?t well grounded or else
the wires bad or open from the Gens Field post up to the switch. INSURE THAT GOOD SWITCH GROUND AND WIRING

6. If she still don?t charge, leave the Field grounded and jump a wire across from the VR or Cutout Relays BAT terminal over to its GEN terminal (jump by passes the
cutout relay) and see if she charges. If then but not otherwise, a VR's cutout relay isn?t working correct (maybe points burned/carboned) or a Cutout Relays NOT
working or not wired correct.

7. With the 2 steps above, you have basically by passed the VR or Cutout relays functions, so if she still don?t charge, you're left with a bad battery or wiring or
the Gen itself.

8. MOTOR TEST. You can Motor test the Gen. If its grounded and you remove the belt and apply hot battery voltage direct to its ARM Post and have the Field Post dead
grounded to frame, it should motor n run well (Armature n Brushes and Commutator likely okay). Then, if you next remove the Fields ground and it speeds up some, the
Fields probably good. If it passes both those tests, it should charge, and if not, it may be a wiring or battery or grounding problem. The hot battery voltage may be
taken off the VR's BAT terminal or the starter post or the battery itself for this test.

9. Typical Gen problems may be the brushes are worn down or the hold down spring assemblies are stuck/corroded/dirty and arent pushing the brushes tight down against
the commutator. Check those things out. Worse may be bad fields or armature etc. Air and WD 40 etc can clean and free them, the hold downs must be free n snap and hold
the brushes DOWN TIGHT and they cant be worn down too low.

SUMMARY: Check the wiring,,,,,the grounds,,,,,,insure BAT on VR or Relay is hot,,,,,,,check battery (maybe load tested and Specific Gravity checked),,,,,,,,,good tight
belt,,,,,,,insure ammeter is continuous (BOTH sides HOT),,,,,,see if battery voltage rises above 12.6 (half that for 6 volt system) and/or light glow
brighter,,,,,,,,,do the Field and cutout relay VR by pass checks,,,,,,,,insure the Gens brushes arent worn down and the hold down springs are free n clean and push the
brushes down tight,,,,,,,,,,,check the connections,,,,,,,,,try the Gen Motor Test to see if its good.

You may just have a bad battery or bad ground or connection if the Gen and VR or relay are okay. Good Luck n God Bless, let us all know.

John T Nordhoff in Indiana, retired Electrical Engineer
 
Terry, the common experience of some here (including me) is that finding a good and reliable regulator is getting more and more difficult. Most of them made in China just don't work long term. Some barely make it short term.

It's been suggested to get a "good one" from somewhere like "NAPA", but you have to take into consideration that generator systems of the 20's-60's were never as reliable or as efficient as the alternators which replaced them. If someone was to mass produce a tractor today equipped with gen/reg technology 80 years old, you'd think they were knutz, and you'd be right.

Unless you are intending to make this tractor a restoration, don't fret or apologize to the "correct police" for making it functional for you by going to 12V and putting on an alternator.
 
Yup, if my pockets were deep right now and I had nothing to do I would convert to the alternator. Keep all the stuff that I changed out and run 12volt negative ground. Not look back and would out last me easily.

I sort of take this situation as a challenge. I had another tractor that never gave me a like of problems. This one makes me want to learn what is really causing this.

I ordered what I though was a good voltage regulator, had the appearance of the original by the picture. What showed up was the simpler square box el-cheap-o.

Thanks, Terry




(quoted from post at 16:09:39 06/15/17) Terry, the common experience of some here (including me) is that finding a good and reliable regulator is getting more and more difficult. Most of them made in China just don't work long term. Some barely make it short term.

It's been suggested to get a "good one" from somewhere like "NAPA", but you have to take into consideration that generator systems of the 20's-60's were never as reliable or as efficient as the alternators which replaced them. If someone was to mass produce a tractor today equipped with gen/reg technology 80 years old, you'd think they were knutz, and you'd be right.

Unless you are intending to make this tractor a restoration, don't fret or apologize to the "correct police" for making it functional for you by going to 12V and putting on an alternator.
 
Try getting an older original off ebay or maybe in classifieds here. Clean it up and see if it works. Had similar probs with my 200. Have two vrs, after cleaning up (in/out) one still does the same as yours. Second lucked out and is charging for me.
 
Interesting. Makes wonder if there is an adjustment problem with them. Maybe not set up at the factory right.



(quoted from post at 19:10:27 06/15/17) Try getting an older original off ebay or maybe in classifieds here. Clean it up and see if it works. Had similar probs with my 200. Have two vrs, after cleaning up (in/out) one still does the same as yours. Second lucked out and is charging for me.
 
I swear I've seen discussions here over the years about adjusting them. Searched and searched and gave up when I remembered that dusty vr sitting on the shelf!
 

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