alternators REO

[johan77]

hi guys,

who has a prestolite alternator in his deuce and who has a leece-neville one ?? according to a shop nearby they are the same for mounting, (even the NSN and part number should be the same) except that with the prestolite all the turning-moving parts are in the housing and with the leece neville one there is some sort of rotor on the outside. Any pro's and contra's ? oh yeah, its the one for 60amps

Thanks

 

[NDT]

The Prestolite design is what was used going forward and lots of us here will tell you it is a failure prone unit. The older Leece Neville seemed to be more durable. But either will go poof if you reverse polarity it.

 

[johan77]

The Prestolite design is what was used going forward and lots of us here will tell you it is a failure prone unit. The older Leece Neville seemed to be more durable. But either will go poof if you reverse polarity it.

thanks, but the mounting is the same like the prestolite ?

 

[NDT]

Yes same.

 

[johan77]

Yes same.

Thank you sir !!

 

[rustystud]

The Prestolite design is what was used going forward and lots of us here will tell you it is a failure prone unit. The older Leece Neville seemed to be more durable. But either will go poof if you reverse polarity it.

Yeah, these early model alternators don't stand up well. Now the newer Delco replacement units can "take a licking and still keep on ticking" !

 

[johan77]

Yeah, these early model alternators don't stand up well. Now the newer Delco replacement units can "take a licking and still keep on ticking" !

Is it true that you should start the deuce Always with lights on ? someone told me that the alternator has to deliver its produced output power somewhere because if batteries are full, and no users are switched on, it is very bad for them alternators, (because the produced electricity can't go anywhere)
Thanks

 

[NDT]

No that is false. As the batteries come up to full charge after having been discharged by cranking, the voltage regulator inside the alternator senses the voltage getting higher and holds the output steady at 28 volts, at which time the batteries no longer need charging and no current flows to them anymore, and the output of the alternator goes to just enough amps for the fuel pump.

 

[johan77]

No that is false. As the batteries come up to full charge after having been discharged by cranking, the voltage regulator inside the alternator senses the voltage getting higher and holds the output steady at 28 volts, at which time the batteries no longer need charging and no current flows to them anymore, and the output of the alternator goes to just enough amps for the fuel pump.

this will be a not so smart question maybe but Besides the gauge on the dash (wich should be in the green zone when running (idle), how can you be sure the alternator and regulator are fine , in working condition ? with fully charged batteries and no users, the reg. reduces the power to minimum...and still the gauge should be in the green ?

 

[NDT]

Yes. The little white mark in the green field is 28 volts. If the alternator malfunctions that gauge will tell you the entire story.

 

[johan77]

Yes. The little white mark in the green field is 28 volts. If the alternator malfunctions that gauge will tell you the entire story.

that was exactly what made me thinking...i have a bad alternator (broken/worn out rotor) and still the gauge was reading halfway green....when hooking up a new gauge that one is halfway yellow, and still measuring 24.2 volts at the wire from that gauge. so when delivering 27.6 volts that one should be close to halfway green. i ordered a new alternator and will see what happens. The only thing what does not work at all are the entire light system (but the 3 lever switch unlock switch is broken inside, i hope replacing the switch assembly solves the issue for the lights) and i hope the light circuit does not caused the alternator to break down, although the guy from the shop told me is because of age, worn out, and was full of dry men windings and rotor and all)

 

[Tow4]

that was exactly what made me thinking...i have a bad alternator (broken/worn out rotor) and still the gauge was reading halfway green....when hooking up a new gauge that one is halfway yellow, and still measuring 24.2 volts at the wire from that gauge. so when delivering 27.6 volts that one should be close to halfway green. i ordered a new alternator and will see what happens. The only thing what does not work at all are the entire light system (but the 3 lever switch unlock switch is broken inside, i hope replacing the switch assembly solves the issue for the lights) and i hope the light circuit does not caused the alternator to break down, although the guy from the shop told me is because of age, worn out, and was full of dry men windings and rotor and all)

If you haven't already done it, you should be measuring the voltage at the batteries with a DMM before you decide the alternator is bad. The installed volt meters are not that accurate. The volt meter in my M929 reads in the middle of the yellow but the batteries are at 28 volts with the engine running.

FYI, the Delco clones are as good as or better than the OE. The company I worked for bench marked and ran durability tests during the vendor approval process for many different models and they were mostly very good.

 

[johan77]

If you haven't already done it, you should be measuring the voltage at the batteries with a DMM before you decide the alternator is bad. The installed volt meters are not that accurate. The volt meter in my M929 reads in the middle of the yellow but the batteries are at 28 volts with the engine running.

FYI, the Delco clones are as good as or better than the OE. The company I worked for bench marked and ran durability tests during the vendor approval process for many different models and they were mostly very good.

never had more than 24.2 volts on the batteries, nor on the wire connected on the volt meter in the dash. i took it to a specialized shop to have the alternator tested (after changing the regulator, because i thought that one was the problem, but unfortunatly) and it turned out the rotor is faulty , the alternator doesn't deliver any electricity. I'ts not that cheap so i ran all options to make sure what needs to be done. and without a working alternator its not recomended to work on the lights and electrical system, batteries are new and i want them to go some time still.