Need help--adapting a generic volatage regulator

[PHIL850]

FYI: I believe the markings refer to the following:

F- for Field, A- for Armature and B- for Battery.

regards, Phil C.

 

[zzvyb6]

You might try a local junk yard filled with old Mitsubishi, Subaru, Datsun or Toyota vehicles. They would have had your voltage regulator parts in them from my experience. Tractor regulation is different from car regulation because tractors are usually run at higher average rpm and hours than a car. This means the charging systems have much less wattage, too. A junk yard is a reasonable place to walk around in with your old mount in hand to see what will fit in the engine location, offset and belt winding (direction, too). My Yanmar ate a regulator and it was VERY expensive ($80) to replace. Turns out it was the wire attached to the terminal inside the can. The problem was initiated by a bad battery terminal. The inability to pass low charging current caused the regulation to stay high all the time. This overheated the connector. I found this out when the new regulator also failed. I fixed this one based on disassembling the previous one. BTW: The tractor started fine because the high current draw of the starter bridged the corrosion in the battery terminal. The very low charge current could not.
Good luck. Bottom line: clean battery terminals and connectors as part of routine maintenance. Replace terminal end if necessary. Watch for corroded wire ends, too.

 

[Soundguy]

Ashas been said.. a=armature.. f=field, b=battery.. case may be ground.

No diodes in mechanical vibrating contact relay.

Mechanical voltage regulators generally fall into 2 categories.. A circuit, and B circuit.. and don't be surprised that some genny and alternator regulators will work on either unit.. genny or alt.. etc.

You need to decide which circuit it is... A or B

A circuit: regulator field tab provides 'ground' to the field coils in the genny.

B circuit: regualtor field tab provides 'power' to the field coils in the genny.

start tractor,
If reg type is's unknown.. start testing it. Grab a test lamp with a gator clip... hook clip to ground.. poke test probe to f contact on genny

jumper arm to battery... this bypasses the cutout.. if the ampmeter registers a charge when you hit the probe to the f tab ont he genny.. it is a circuit. if nothing, then hook gator clip of probe to battery hot, and then poke the f tab ont he genny again... if the ammeter registers a charge, then it is B circuit.

You don't mention.. but i am guessing 12v?

While you really should find what value the field coils are.. if it does turn out to be a 12v B circuit unit.. just grab a regulator for a ford diesel hundred series tractor... they will be 12v b circuit regulators.

I'm surprised that your repair shop couldn't have sourced parts for you.

I have an old hitachi alternator on my yanmar 1700.. it uses an old style chrysler regulator onit.. works fine...

Post back if ya need more help.

gennies are fairly bullit proof...and fun to work on they either need field power.. or field ground.. just depends where the field coils are hooked up internally ( to arm or case.. )

Remember to unjumper/bypass the arm / battery connection after your test.. otherwise the genny will discharge your battery..

Soundguy

Here are the pictures of the current non-functional regulator. As I was taking the pictures, I started wondering...

What if just the diodes were bad? Can they be replaced? they've got numbers on them, but you can't quite see it in the picture. Could I bridge them and see if things started working?

Also, as you can see from one of the pictures, there are three tabs in front...A F B. Presumably, two would come from the generator and one would go to the battery. B= battery...could it be that simple? What would A and F stand for? How would I know (guess) which posts on the generator they'd correspond to?

Thanks in advance,

-Steve

 

[srjones]

Mechanical voltage regulators generally fall into 2 categories.. A circuit, and B circuit.. and don't be surprised that some genny and alternator regulators will work on either unit.. genny or alt.. etc.

You need to decide which circuit it is... A or B
A circuit: regulator field tab provides 'ground' to the field coils in the genny.
B circuit: regualtor field tab provides 'power' to the field coils in the genny.

That sounds like the question to answer. From there, hopefully I can find a suitable replacement.

start tractor,

I would if I could, but the reason I went to the shop in the first place was a dead starter.

If reg type is's unknown.. start testing it. Grab a test lamp with a gator clip... hook clip to ground.. poke test probe to f contact on genny

jumper arm to battery... this bypasses the cutout.. if the ampmeter registers a charge when you hit the probe to the f tab ont he genny.. it is a circuit. if nothing, then hook gator clip of probe to battery hot, and then poke the f tab ont he genny again... if the ammeter registers a charge, then it is B circuit.

You don't mention.. but i am guessing 12v?

yep, 12V

I'm surprised that your repair shop couldn't have sourced parts for you.

Oh, I'm sure they could have. However, I didn't ask. I'm still reeling from the repair bill on the starter. When I go back on Monday, I can. Even better, I can ask an intelligent question like:

Does this generator require a 'b circuit' or an 'a circuit' regulator?

Post back if ya need more help.

Will do, thanks

 

[srjones]

Hi Soundguy...you got me thinking and reasearching and I found something on a different forum.


Yesterday's Tractors - Discussion Forum

Heres a quick check on the regulator. Flip it over.. look for the bias resistor.. An A circuit regulator should have a bias resistor between the field contact and ground on the regulator. On a B-circuit regulator there should be a bias resistor between armature and field.. there may be other bias resistors present.

Sound familiar?

Anyway, I did just that, and I'm pretty sure it's a "B circuit". The picture I uploaded at the start of this post doesn't label it, but the tabs on the right are the field and armature.

Thoughts?

http://www.tractorbynet.com/forums/...d-help-adapting-generic-volatage-p1050483.jpg

 

[Soundguy]

That's my post you are quoting from ytmag..... and it generally hold true. Your reg is a bit more hi tech than the old ford regs that use only 1 or 2 bias resistors.. however.. my 'bet' is that it is b-circuit as well.

Once you get the tractor started, it will be easy to check. Wire it all back up to the reg.. start tractor, hook up gator clip to power, and take the probe of the test lamp and hit the field tab... if the ammeter doesn't go + then jumper arm and bat and repeat.

Also.. I didn't mention it.. but gennies and regs need to be polarized.

B circuit polarizes by jumpering bat to field momentarilly.

Uh.. don't do that part untill you figure out if it is really B circuit. Jumpeirng bat to field on an a-citcuit reg can burn field points.. faster than a nats wings..

Soundguy

 

[srjones]

Thanks Soundguy...yeah, I knew it was your quote.

So assuming that the regulator is correctly diagnosed as being bad, what would be my best (cheapest) option to replace it?

 

[Soundguy]

Well.. see what the 'shop' will charge you. I usually buy mech regs in the 25-40$ range.

If it is B circuit.. and 12v.. I'd seriously considder a ford diesel hundreds series reg.. as they will be 12v and b-circuit.

I have one here on my desk as a backup for the old shoddy lucas regulator that is on my ford 5000. The part number is 1406 12V P/N says made in use on it.. blue housing and metal base.. 3 tab.. A,F,B bottom has another #1CD

I'd probably look for something like that.. unless the oem reg the shop finds is similar in price.. then go with that.. etc.

At issue is the original field coil resistance.. and what current it was designed for... It may not be exact.. but should be close enough to work. If you don't plan to suck every ounce of power out of the system.. the mismatch won't be noticed probably.

Soundguy

 

[slowrev]

If the fit is tight go with a small one wire alternator. I think my Subaru uses a little 60 amp Hitachi with internal regulator. About 30% smaller that a delco 10SI.
Ben.