800 Special Generator Issue

["Manic-Mechanic" 1,194]

Well, I went with this circuit and the generator really isn't charging, quite the opposite. I measure voltage across my terminals prior to starting and I get almost 13 v. Once running the voltage drops on my multimeter to 12.35 v. The voltmeter gauge remains at a steady 12v. I do not want to keep it running if there is an issue...The light I used for the warning light off the ignition begins to glow once throttled up, so my generator is not charging. The field terminal does read 12 v with the ignition off. Now I'm under the impression the generator is not in fact "generating?" The light bulb is rated 28 v, perhaps it is causing an issue, not sure

 

Edited June 24, 2022 by "Manic-Mechanic"

[adsm08 2,002]

With the engine running, and your volt meter hooked to the battery, ground the field terminal of the S/G unit and monitor voltage. If it spikes high, the regulator, or its wiring, is at fault. If voltage stays low it is time to get the S/G unit rebuilt.

 

There is a guy in our general area (Red Lion maybe) that supposedly still does that work, but I can't remember who. Hopefully one of the other SEPA members will chime in knowing who it is.

["Manic-Mechanic" 1,194]

7 minutes ago, adsm08 said:

With the engine running, and your volt meter hooked to the battery, ground the field terminal of the S/G unit and monitor voltage. If it spikes high, the regulator, or its wiring, is at fault. If voltage stays low it is time to get the S/G unit rebuilt.

 

There is a guy in our general area (Red Lion maybe) that supposedly still does that work, but I can't remember who. Hopefully one of the other SEPA members will chime in knowing who it is.

I cannot find a wiring diagram for this regulator and it isn't marked AQP 1400-0572. There is a terminal underneath but not even sure what it is for? Who would make a regulator with no markings, stupid

[gwest_ca-(File Mod) 11,026]

This old Kohler service manual has a good section on the starter/generator.

One here also by Briggs and Stratton

 

["Manic-Mechanic" 1,194]

34 minutes ago, gwest_ca said:

This old Kohler service manual has a good section on the starter/generator.

One here also by Briggs and Stratton

 

I have all of your manuals they will not help too vague, thank you. the regulator has no marking anywhere with three terminals and one underneath. I will go through the manuals once again see if I missed something, thanks. Yes, I missed a lot! Maybe time to give it a rest, happy it started right up and didn't have end play issue!

Edited June 24, 2022 by "Manic-Mechanic"

[adsm08 2,002]

16 minutes ago, "Manic-Mechanic" said:

I cannot find a wiring diagram for this regulator and it isn't marked AQP 1400-0572. There is a terminal underneath but not even sure what it is for? Who would make a regulator with no markings, stupid

 

The F terminal should also be marked on the body of the S/G, but it is the wire connecting the generator to the regulator.

["Manic-Mechanic" 1,194]

Just now, adsm08 said:

 

The F terminal should also be marked on the body of the S/G, but it is the wire connecting the generator to the regulator.

Yes, I know the field wire well, it is the other three that concern me as none are marked or labeled, had this issue with parts before and had to open them up to see what's, what. Thanks

["Manic-Mechanic" 1,194]

I see on the diagram above a wire from A to a terminal marked GEN, could that be the one terminal underneath my regulator? Here is what I am looking at from gwest_ca  might be my issue the additional wire to G from A?

Edited June 24, 2022 by "Manic-Mechanic"

[adsm08 2,002]

3 minutes ago, "Manic-Mechanic" said:

I see on the diagram above a wire from A to a terminal marked GEN, could that be the one terminal underneath my regulator? Here is what I am looking at from gwest_ca  might be my issue the additional wire to G from A?

 

Yes, the A terminal on mine is down below, and hard to access.

 

I remember this because it is one of the ones that has to be jumpered to polarize the regulator.

["Manic-Mechanic" 1,194]

2 minutes ago, adsm08 said:

 

Yes, the A terminal on mine is down below, and hard to access.

 

I remember this because it is one of the ones that has to be jumpered to polarize the regulator.

That would totally explain the readings I am getting, seems to me I had this issue decades ago on a Sears...

Edited June 24, 2022 by "Manic-Mechanic"

["Manic-Mechanic" 1,194]

Thanks once again everybody! Sorry for being "short", getting close to done, anxious....

[adsm08 2,002]

1 minute ago, "Manic-Mechanic" said:

That would totally explain the readings I am getting, seems to me I had this issue decades ago on a Sears...

 

Yeah, at one point I was taking my 855 apart so often for various electrical issues that I left a wire alligator-clipped to the A-terminal and looped off and capped for quick access because I was polarizing the regulator a couple times a week. Then I got my issues fixed (mostly) and took it off.

["Manic-Mechanic" 1,194]

8 minutes ago, adsm08 said:

 

Yeah, at one point I was taking my 855 apart so often for various electrical issues that I left a wire alligator-clipped to the A-terminal and looped off and capped for quick access because I was polarizing the regulator a couple times a week. Then I got my issues fixed (mostly) and took it off.

I was just debating what color to use, an alligator clip would be smart. I loosened the inside screw and removed the other, regulator slides right off. Here goes nothing! Lol

["Manic-Mechanic" 1,194]

Well, I set it up as indicated and that was not good! I parked it back in the shop as the carburetor seems off as well. She will run, that's half the battle!

[Ed Kennell 37,985]

3 hours ago, adsm08 said:

 

 

There is a guy in our general area (Red Lion maybe) that supposedly still does that work, but I can't remember who. Hopefully one of the other SEPA members will chime in knowing who it is.

 

That would be Bill Mundis in Springvale, Pa.   Just South of Red Lion.

[adsm08 2,002]

25 minutes ago, Ed Kennell said:

 

That would be Bill Mundis in Springvale, Pa.   Just South of Red Lion.

 

Thanks. I still have a few on my shelf that need redone, and I'd lost his info, couldn't remember if it was you that I got it from, or someone else.

["Manic-Mechanic" 1,194]

18 hours ago, adsm08 said:

 

Thanks. I still have a few on my shelf that need redone, and I'd lost his info, couldn't remember if it was you that I got it from, or someone else.

I am going to have an alternator shop check out both the generator starters that I have. I do not trust the "old school" quick test as I have tried yet a second regulator with same results. The engine runs excellent so happy with that. This engine was a former magneto system turned over to 12 v battery, this should not interfere with the charging system. All my grounds are clean and there is nothing else I can think of. Cole Hersey 3 prong heavy duty ignition. # 6 wire short as possible. Missing something, has to be the generator? 

Edited June 25, 2022 by "Manic-Mechanic"

[adsm08 2,002]

11 minutes ago, "Manic-Mechanic" said:

I am going to have an alternator shop check out both the generator starters that I have. I do not trust the "old school" quick test as I have tried yet a second regulator with same results. The engine runs excellent so happy with that. This engine was a former magneto system turned over to 12 v battery, this should not interfere with the charging system. All my grounds are clean and there is nothing else I can think of. Cole Hersey 3 prong heavy duty ignition. # 6 wire short as possible. Missing something, has to be the generator? 

 

1) Did you do them engine running full-field test?

 

2) It is possible for an alternator to fail in a way that it produces proper voltage, and almost no amps, but I'd only seen it once or twice, and those were A/C automotive units. I think these SG units put out DC, and don't know if it's possible for them to fail the same way.

 

But yes, if a second regulator causes the same issue, the generator is likely the cause.

Edited June 25, 2022 by adsm08

["Manic-Mechanic" 1,194]

4 minutes ago, adsm08 said:

 

1) Did you do them engine running full-field test?

 

2) It is possible for an alternator to fail in a way that it produces proper voltage, and almost no amps, but I'd only seen it once or twice, and those were A/C automotive units. I think these SG units put out DC, and don't know if it's possible for them to fail the same way.

Yes, even though the tests show the unit should work it actually brought the voltage down/. I'll have an overhaul on it next week and bring both to a shop I know of, (before they have gone the way of the dodo) 

Edited June 25, 2022 by "Manic-Mechanic"

[adsm08 2,002]

Just now, "Manic-Mechanic" said:

Yes, even though the tests show the unit should work it actually brought the voltage down/ I'll have an overhaul on it next week and bring both to a shop I know of, (before they have gone the way of the dodo" 

 

If the voltage dropped during a full field event you have a generator issue. Full-field should do two things with a properly working generator on an engine this size.

 

1) It should load the thing up so heavy you lug, or even stall, the engine.

 

2) It should shoot the voltage up above 15 volts.

 

I worked on a Windstar van some years ago for an intermittent charging light, and I found if I held the voltage regulator just so I could make the belt slip and get the 12V alternator to put out 24V.

["Manic-Mechanic" 1,194]

21 minutes ago, adsm08 said:

 

If the voltage dropped during a full field event you have a generator issue. Full-field should do two things with a properly working generator on an engine this size.

 

1) It should load the thing up so heavy you lug, or even stall, the engine.

 

2) It should shoot the voltage up above 15 volts.

 

I worked on a Windstar van some years ago for an intermittent charging light, and I found if I held the voltage regulator just so I could make the belt slip and get the 12V alternator to put out 24V.

I built the engine and she wants to run and the rest of the tractor is in very good shape. My last complete build so now I am in it until it's done ! Lol The last k 241 generator starter set up was on a 1045. Whenever I ran that tractor the generator would have a specific sound, like you knew you were riding a piece of history. This unit made no sound while running. Things keep going south, last run the c clip came off the throttle to governor, she started going very fast, very quickly! Lol I will not quit until it is right one way or another! Worse case scenario I swap engines and systems to a  NOS Subaru Wisconsin 13hp. Trying to keep it Red tho"

["Manic-Mechanic" 1,194]

I installed an old Delco off a Jacobsen reel mower, it was rigged here and there as the A Terminal is broken!

However, it showed excellent charge and the warning light did not come on at all! So, to the shop, at least I know all is well....