Generator output?

[oldgreentrucks]

Question is how to best evaluate the generator output to support a 24v electric winch on M38A1.
Thanks for feedback.
Jim

[Ryan_Miller]

First start here with some of the basics on the download site of this website:
http://www.willysmjeeps.com/v2/modules. ... oad&cid=57

Testing data can be found there too.

[oldgreentrucks]

Thank you Ryan!

[wesk]

The stock system is only rated at 24 volts and 25 amps. I think you would fair better with converting to a 24 volt and 60 amp military alternator. For estimating power needs figure 15 amps for the jeep plus whatever stall load amp rating is on your winch.

[oldgreentrucks]

Wes,
Thank you as always for the precise accurate information. What is involved converting from stock Generator setup to the 24v 60 amp Alternator system. Is this a common conversion? Part # etc...?
Thanks for the help.

My second choice is I have a complete PTO unit, shaft, Koenig winch from a CJ3A. Would require rerouting the exhaust at a mimimum?
Jim

[wesk]

Depends on your goal of restoration level of the jeep. The Koenig will work just fine if you don't mind reworking the exhaust system layout or converting to the CJ3A exhaust.

The 60 amp alternator conversion is very simple. The alternator itself is a bit spendy but I think it's worth it. It fits right in the original mount bracket. It is a 2 wire install and has a built in regulator. So you remove the original 25 amp generator, regulator, large interconnecting cable and remove the wires (#4, 8, 9 & 10) from the firewall plug for the original regulator. You terminate wires 8 & 9 that were in that plug (they are for the old amp meter). You connect wire #4 to the alternator large output terminal. You connect wire # 10 to the battery terminal on the starter. You install a voltmeter in place of the amp meter. This is the GI issue color coded generator charge indicator. You connect the + lead from the new volt meter to the #27, 12, or 85 wire from the master switch. You connect a 16 gauge wire from the small terminal on the alternator to the #27, 12 or 85 wire from the master switch. The voltmeter ground should be connected with a new 16 gage wire to the firewall. That's it.

Alternator - Prestolite AMA5102UT, FSN 2920-909-2483
Volt meter (Generator condition gage) M. V. Volt Gauge - Douglas Connector! NSN: 6625-00-335-9512, P/N: SW 504 E.

or this one can be adapted as well:
New!! M. V. Volt Gauge w/rubber Packard connector. NSN: 6625-01-086-9580, P/N: GP-504-AB or MS 24532-2


The gauge can be purchased from Saturn Surplus:
http://www.saturnsurplus.com/gauges/gauges.htm

The military 24V 60A alternator can be purchased from:
http://search.store.yahoo.net/yhst-5952 ... afora.html
http://compare.ebay.com/2920-00-909-248 ... 0192716611

Alternatively you could just buy a civilian Delco 24V 60A two wire alternator and make a mount bracket for it.

The 5 and 6 leg spider harness' make attaching the two wires behind the dash easier also.

[Beacher425]

For the rubber connector gauges, is the power connector the one with the raised ribs? Looking at the rear of the gauges, the connector on the left has raised ribs and the one on the right is smooth.

Thanks

[wesk]

Looking at the instrument cluster from the rear the power in is on the right for both metal and rubber connector gauges.

[Beacher425]

Thanks!

[Beacher425]

I have read that all wires on the M38A1 are 14g with the exception of the battery cables at 2g, the #4 wire at 8g, and the #10 wire at 12g. Is this true with both the stock generator setup and a switch to a modern 1 wire alternator? Could 10g be used for the #4 wire?

Thanks

[wesk]

I used 10 Ga on my M37 60 amp alternator set-up. It is a tough fit under the terminal box cover on the alternator. I just left one of the two screws off so the cover can sit a tad higher.

The widespread use of the 16Ga was actually overkill but was based on rough service. If you do the electrical math most of the jeep circuits would have been served just as well with 16 Ga and in lighting circuits except the headlights 18 Ga. would have been fine.