Question on RPM limiter & carb

[Joseph Cummings]

3 minutes ago, Joseph Cummings said:

Yeah They let out a nasty stink when they burn out lol

BTW your son's honda should have had a Zener diode in the circuit. They leak in reverse flow at a certain voltage

Just be glad that none of this was designed by Joe Lucas

Yeah that's what he's got. I haven't seen one of them in like 40 years lol

[Geoff Weeks]

https://www.prestolite-eu.com/Category/C0011111CA

you could tuck one of these somewhere on  the truck and leave the original for "show".

Ahh, see "discontinued" but there may be others.

Edited February 14 by Geoff Weeks

[T-Mack1]

The Leece Neville ALT (100 amp) has 4 leads coming out. (maybe 3-phase plus a ground??) The tag on the ALT has "Rectified" and "Rotation reversible".   I would post a pict but I didn't realize I had to be careful on size and used up my limit.

[Geoff Weeks]

If you don't care about "period correct" than a JB series alternator will bolt in place.

I have the same unit but in 6 volt.

The "extra" wire is the field connection. On my picture, the brushes have been removed, so the terminals are not visible.

[Joseph Cummings]

11 minutes ago, T-Mack1 said:

The Leece Neville ALT (100 amp) has 4 leads coming out. (maybe 3-phase plus a ground??) The tag on the ALT has "Rectified" and "Rotation reversible".   I would post a pict but I didn't realize I had to be careful on size and used up my limit.

 

[T-Mack1]

A friend of mine asked off-line if it could be a Dual-Charge system.  In other words, a redundant system to charge Battery A and Battery B separately.  We do have two Ammeters and the battery A / Battery B switch on the dash..

Did they do that on some of the fire trucks????

 

 

[Geoff Weeks]

I'm not seeing anything that looks different than a L/N Alternator of that era. 

[Joseph Cummings]

51 minutes ago, T-Mack1 said:

A friend of mine asked off-line if it could be a Dual-Charge system.  In other words, a redundant system to charge Battery A and Battery B separately.  We do have two Ammeters and the battery A / Battery B switch on the dash..

Did they do that on some of the fire trucks????

 

 

It seems like if you wanted to do something like that, you would need 2 of those selenium full wave rectifiers and I'm only seeing one. That system is electrically the same as a modern alternator. The only difference is the modern alternator uses diodes that are small enough to fit inside the housing. Those old selenium rectifiers were huge in comparison to a modern rectifier using diodes. Actually if that selenium rectifier burned out, you could replace it with 6 diodes and not change anything else. It would function exactly the same. Lots of times doing repairs to old machinery I replace burned out selenium rectifiers with diodes. Functionally they are the same, just an electrical version of a "check valve"

[Geoff Weeks]

Modern diodes would have no problem with the100 amps the alternator could produce,but are designed to be cooled by the alternators fan drawing air over them. 

On mine, I'm looking into making an add on rear cover that can support and isolate JB diode sets on the alternator itself while ducting the air drawn in by the alternators cooling fan.

There is also a version of this alternator that was made for military, 24 volt that I believe has internal diodes. I suspect that the rear housing could be swapped but haven't found one cheap enough to look further into it.

 Mine and I assume the 12 volt one, use a bar wound stator, like a starter motor, unlike modern wire wound units.

[Joseph Cummings]

Oh, btw. You can hook a transformer with a 10 to 1 windings ratio to that 12ish volt ac output of the alternator, and end up with a 120ish volt AC supply. The frequency will be all over the place with variations in engine speed, but it's fine for incessant lamps and universal ac/dc power tools. 

We used to do that back in the day with modern alternators by tapping into the 3 phase armature connections before the rectification and sneaking the wires out the back

[Joseph Cummings]

Just now, Geoff Weeks said:

Modern diodes would have no problem with the100 amps the alternator could produce,but are designed to be cooled by the alternators fan drawing air over them. 

On mine, I'm looking into making an add on rear cover that can support and isolate JB diode sets on the alternator itself while ducting the air drawn in by the alternators cooling fan.

There is also a version of this alternator that was made for military, 24 volt that I believe has internal diodes. I suspect that the rear housing could be swapped but haven't found one cheap enough to look further into it.

 Mine and I assume the 12 volt one, use a bar wound stator, like a starter motor, unlike modern wire wound units.

Yeah well you have to do it right with heatsinks and airflow for thermal management. There are always going to be I2R heating considerations

[Geoff Weeks]

https://www.ebay.com/itm/134992311495?_skw=military+alternator&itmmeta=01JM56DHY71RX68ZB4SW7340CB&hash=item1f6e2b34c7:g:FRYAAOSwVL1mAWfV&itmprp=enc%3AAQAKAAAA8FkggFvd1GGDu0w3yXCmi1c67QP3vaHzNB002bkvPLALu08M0vdP2S1AfXEsjc5Lc5P04Cu%2BhKvUzFVv695fWHe00GzEifoLmSugsfRU9IlDt%2Bg%2BOyB8LZ%2FYSCX%2BGOiSHKhO9dMYMmrR5LoToDLiE6HpO2FqfQL5CSaABJXrhpuwxgIAyijnE3wo4%2BcSQy8WGSxgRjTBLKwAM95S1Zr3%2Brx58XpURrErzQPcYBmo7rJi57OogrD7wLi7SIPi68xkoFVIo63LeDb5W6J8feDODUQpjLPlB3UWh1PFDT33ogtpAiN6avrmk576NmqFJPrMeQ%3D%3D|tkp%3ABk9SR6qftqahZQ

This is the type I'm talking about, but non working I am only willing to pay 1/10th that to experiment  with.

[Joseph Cummings]

7 minutes ago, Geoff Weeks said:

https://www.ebay.com/itm/134992311495?_skw=military+alternator&itmmeta=01JM56DHY71RX68ZB4SW7340CB&hash=item1f6e2b34c7:g:FRYAAOSwVL1mAWfV&itmprp=enc%3AAQAKAAAA8FkggFvd1GGDu0w3yXCmi1c67QP3vaHzNB002bkvPLALu08M0vdP2S1AfXEsjc5Lc5P04Cu%2BhKvUzFVv695fWHe00GzEifoLmSugsfRU9IlDt%2Bg%2BOyB8LZ%2FYSCX%2BGOiSHKhO9dMYMmrR5LoToDLiE6HpO2FqfQL5CSaABJXrhpuwxgIAyijnE3wo4%2BcSQy8WGSxgRjTBLKwAM95S1Zr3%2Brx58XpURrErzQPcYBmo7rJi57OogrD7wLi7SIPi68xkoFVIo63LeDb5W6J8feDODUQpjLPlB3UWh1PFDT33ogtpAiN6avrmk576NmqFJPrMeQ%3D%3D|tkp%3ABk9SR6qftqahZQ

This is the type I'm talking about, but non working I am only willing to pay 1/10th that to experiment  with.

I've converted 12v Delco SI alternators for 24 volt systems. Different rotor, different regulator. Armature and rectification was the same

[Geoff Weeks]

No, that is not where I am going with this. The rear section houses the diodes and I believe would bolt on to these early alternators, providing a pre made update to internal diodes, as well as the ducting required to cool them.

 Both these old alternators and the military units, use the screw in staggered brush holder that are outboard of the rear bearing, like modern Prestolite units are.

It looks like the rear housing could replace the rear housing on these old units.

For most automotive alternators the stator determines current capacity and the field determines what voltage they're made for. A 12 volt will produce 6 volts with a 6 volt regulator, but with the field being so much weaker the output is low and cut in speed high. Replace the field with a 6 volt one, or re-wind it will produce its name plate current.

 Most truck alternators use the same stator for 12 or 24, once you go to 32,36, or 48 the stator changes in most units.

Edited February 15 by Geoff Weeks

[Joseph Cummings]

That's a Kaiser M715 alternator. 

 

 

[Geoff Weeks]

It was used on many older Military trucks.

If you un bolt and separate at stator (red vertical line) I believe you could remove the rear case on the  Alternator in question, and bolt the rear case containing the diodes (and regulator, but you wouldn't need to use the reg) in place of the original rear case.

I just can find a "dead one" at a reasonable price to try it.

Edited February 15 by Geoff Weeks

[Joseph Cummings]

Yeah it might fit, I know I've bolted Delco SI back halves onto Delco DN alternators. Used the DN rotor also. I built a pair for a Cessna 310 C . I got a lot of BS about it too because they said there wasn't an STC for 10SIs for it. But everyone was fine with the 10DNs that were on it, and guess what,,, There wasn't an STC for the 10DNs either

[T-Mack1]

Figured out where the regulator was, thanks to a post in 2023 that Geoff was helping Angelo.  Saw the picture of Angelo's 7v unit and we have a similar Leece Neville 14v box on the inner driver's side firewall.  Yet another thing to trace wires to-from.   And, yes I know we need to get up close and personal to the alternator to figure out the output leads.  If you look at the picture of our system (below),  you can see the smaller wire going to the alternator, so I assume one of them is the field.  You can't see that there is another small one on there too. 

Plan is to see if the truck runs first.  Which means my task next is double check ignition. I have new parts from Brillman just to see if it runs without funny noises. Then go electronic.   More crawling around......    Lots to look at .... as I sit here watching it snow.

We most likely will convert to modern rectifier.  May actually use my Assoc. Degree in electronics and make one on a large heatsink.  But, also leave the old one there just for looks.  

               

[Geoff Weeks]

Found a Military TM on them, it looks less and less like it would bolt up.

[Geoff Weeks]

3 minutes ago, T-Mack1 said:

Figured out where the regulator was, thanks to a post in 2023 that Geoff was helping Angelo.  Saw the picture of Angelo's 7v unit and we have a similar Leece Neville 14v box on the inner driver's side firewall.  Yet another thing to trace wires to-from.   And, yes I know we need to get up close and personal to the alternator to figure out the output leads.  If you look at the picture of our system (below),  you can see the smaller wire going to the alternator, so I assume one of them is the field.  You can't see that there is another small one on there too. 

Plan is to see if the truck runs first.  Which means my task next is double check ignition. I have new parts from Brillman just to see if it runs without funny noises. Then go electronic.   More crawling around......    Lots to look at .... as I sit here watching it snow.

We most likely will convert to modern rectifier.  May actually use my Assoc. Degree in electronics and make one on a large heatsink.  But, also leave the old one there just for looks.  

               

Three heavy wires are output three phase A/C. the two light ones are field connections. You can use either an "A" circuit or "B" circuit regulator by either connecting one to ground and regulating the hot side of the field or connecting one to the DC output and regulating the ground side of the field.

[Joseph Cummings]

1 hour ago, T-Mack1 said:

We most likely will convert to modern rectifier.  May actually use my Assoc. Degree in electronics and make one on a large heatsink.  But, also leave the old one there just for looks.  

You can probably find the diodes and heat sink you need in an old electric forklift charger. The PIV of the diodes should way more than enough and the amperage should be enough, but I'd check

[Geoff Weeks]

There are plenty of automotive rectifier blocks that could handle 100 amps no sweat, the issue is the cooling. You need to provide some as well as an insulated case to keep them out of harms way.

[Joseph Cummings]

I was thinking forklift charger because they are this type. Easy to mount and rugged

[T-Mack1]

1 hour ago, Joseph Cummings said:

You can probably find the diodes and heat sink you need in an old electric forklift charger. The PIV of the diodes should way more than enough and the amperage should be enough, but I'd check

Or these  https://www.ebay.com/itm/114601767481  (2 for single phase, 3 for 3-phase.)  mounted on a heat sink.  100 amps / 800v

EDIT:  Pin one = inputs,  pin 2 is Neg and if modules are mounted side by side, could use bus-bar to tie them together, and same with POS  pin 3.

Edited February 15 by T-Mack1

[T-Mack1]

37 minutes ago, Joseph Cummings said:

I was thinking forklift charger because they are this type. Easy to mount and rugged

Was looking at those.  Would need regular polarity and reverse polarity diodes ( stud anode and stud cathode). 2 each for single phase (4), and 3 each for 3-phase (6), and would have to isolate the plates the studs are mounted too.