Wiring Questions

This is the place to get help with technical matters concerning your M151 jeep

Moderators: rickf, raymond, Mr. Recovery

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rickf
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Re: Wiring Questions

Unread post by rickf » August 25th, 2017, 9:36 pm

Entendido, gracias por la oferta.

Cuando era joven mi español era aceptable. Crecí en una granja con trabajadores puertorriqueños y luego viví en México por un corto tiempo. Eso fue hace 40 años y como tú no lo usé así que lo perdí. Ahora depende de programas de traductores.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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m3a1
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Re: Wiring Questions

Unread post by m3a1 » August 26th, 2017, 2:20 am

¿No es google traductor maravilloso?

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svramselaar
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Re: Wiring Questions

Unread post by svramselaar » August 26th, 2017, 6:03 am

hi

now i have time for the whole story
below the alternator diagram

Image

it works as follows
engine not running contact on
batts are at B+
control light gets power from the contact it burns it get ground see below
it go from the light to the rotor then to the regulator
at the regulator R1 resistance give power to T1 it opens to the ground
rotor will be a bit magnetic
zener diode Z is at blocking stage

engine running alternator is at battery voltage at +/- 1000 alternator revs
it starts loading the stator give power to the Pos diodes and to the Field diodes
the field diodes take over from the control light
control light gets 24 V from contact and 24 V from field diodes so voltage difference light out

if the voltage get to high zener diode go at zener stage and let the voltage to R2 and the transistor T2
transistor T2 opens and set the power from R1 and T1 at ground
the voltage drops at T1 and closes
rotor get no ground and voltage drops down
zener diode Z closes and the load begins again

the field diodes are +/- 5 amp max
the pos an neg diodes are +/- 80 amps

so if the is no light or a resistance at the D+ the small diodes will try to load also over the wire to the contact
this is possible more than 5 amps and they will be burn out

the stator load go at follows
ground neg diode for example trow stator coil W and V to the pos diode to batts and one field diode
the total voltage 1.73 off one coil there is one coil complete at the rotor magnetism and two not
wen it runs you have a 3 phase alternator

a long store bud now you know how it works

george

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rickf
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Re: Wiring Questions

Unread post by rickf » August 26th, 2017, 9:08 am

Excellent George, that also pertains to most modern 12volt alternators. Not so sure about the military alternators, I was never into one of them.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

elmer
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Re: Wiring Questions

Unread post by elmer » August 26th, 2017, 11:08 am

Thanks George, this explanation is a real master class on how a modern alternator works.
Next Wednesday I will pick up the new alternator and I install it on Sunday. I'll tell you how it works
I still have to decide if I install the light bulb in the part of the wire that is in the engine compartment or if I make a small invention to install it in some hidden part of the dashboard.
Enjoy the weekend and thanks again for your help
Elmer

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Re: Wiring Questions

Unread post by elmer » September 5th, 2017, 6:42 am

I finally fixed the alternator and installed it as george explained; with the bulb on the cable 568 .Now everything works perfectly.
Thanks.

elmer

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Cliffaliff
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Re: Wiring Questions

Unread post by Cliffaliff » August 26th, 2022, 8:39 pm

My 60 amp alternator on my a2 wasn't charging the batteries. After checking all connections many times, I gave up and found an old school auto electrical alternator and starter rebuilder. He put my alternator on the tester, worked normally. I explained my problem. I have a new wiring harness that I installed when I got the mutt. Wire 568 wasn't working. He suggested running a new wire from the alternator to the ignition switch. I had to splice the new wire to the number 12 wire going into the ignition switch. The other end to

the alternator. It worked!!! Charged my batteries. Happy camper!!
1977 M151 A2, Merdc grey desert camo.

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rickf
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Re: Wiring Questions

Unread post by rickf » August 27th, 2022, 8:42 am

Just out of curiosity did you check the connector on the new harness at the end of the 568 wire by the alternator to see if maybe it was a bad connection on that plug? If you can just repair that plug then you have all original harness back. Obviously the #12 wire from the switch to the distributor is good since it runs and the 568 wire splits off of the #12 wire so it has to be either where the split is connected or the plug. Or a broken wire.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Cliffaliff
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Re: Wiring Questions

Unread post by Cliffaliff » August 27th, 2022, 2:14 pm

Yes, I checked everything that I could according to the TM manuals using my multimeter. The very last thing I wanted to do was run a new wire outside of the harness. I am definitely not the smartest guy, but I tried everything. The final test was if I was getting current to #568 while turning on the ignition after unplugging #568 from the alternator. Nothing. So, I had to add the wire. All good now. I do have a question, my alternator puts out 28 volts. Will it overcharge my batteries? Thank you.
1977 M151 A2, Merdc grey desert camo.

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rickf
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Re: Wiring Questions

Unread post by rickf » August 27th, 2022, 2:27 pm

28 volts is exactly what it is supposed to be putting out. You have to charge above standing voltage to get a charge in a battery. When you test a battery a fully charged battery is 12.6 volts and a battery showing only 12 volts is considered dead. Strange but that is how it is worked out in the charts.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Cliffaliff
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Re: Wiring Questions

Unread post by Cliffaliff » August 28th, 2022, 8:32 am

Thank you Rick for the great information.
1977 M151 A2, Merdc grey desert camo.

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