alternator ID

1959 - 1978, M151, M151A1, M151A2, Technical questions and discussions, regarding anything related to the M151.
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11ACRLT
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Location: Marine City, MI.

alternator ID

Post by 11ACRLT » Sat Apr 25, 2020 12:34 pm

How to I identify the model number of an alternator ? The alt on my 151 quit working, the spare I had on the shelf doesn't work either.( it was supposed to have been rebuilt and has never been installed) The TM checks tell me that the field windings are good on both units, the rectifier/regulator checks are suspect on both.
Both are 60 amp units, one has the internal fan and the finned rear cover with the three round pin regulator and the pan style terminal cover, the "new" one is mounted on the vehicle it has the forward mounted external fan, relatively smooth rear cover and the flat plate that covers the terminals .
Thanks in advance for any help.
Curt W Kitter II
'42 MB (sold)
'51 M38
'52 M37 (sold)
'53 M211(sold)
'64 M105A1
'71 M151A2
'72 M35A2C
'72 M561 (sold)
MVPA # 17981
MVCC-MI


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acudanut
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Re: alternator ID

Post by acudanut » Sat Apr 25, 2020 3:21 pm

I am guessing it's on an A2. Are the ground wires looking good ? Did you hook up a voltmeter when running ?

11ACRLT
G-First Sergeant
G-First Sergeant
Posts: 131
Joined: Mon Sep 01, 2008 4:49 am
Location: Marine City, MI.

Re: alternator ID

Post by 11ACRLT » Sat Apr 25, 2020 4:37 pm

Yes it is an A2, volt meter at batteries reads 24.9 volts while running with lights off, batteries read 24.3 volts at rest, no change in output with the adjusting screw on either unit. No tag on the one that was in the vehicle, the "rebuilt" one has a foil tag on it , but its mostly illegible.
Curt W Kitter II
'42 MB (sold)
'51 M38
'52 M37 (sold)
'53 M211(sold)
'64 M105A1
'71 M151A2
'72 M35A2C
'72 M561 (sold)
MVPA # 17981
MVCC-MI

Star Electric Ordnance
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Location: Radcliff, KY

Re: alternator ID

Post by Star Electric Ordnance » Sat Apr 25, 2020 9:51 pm

In all probability, the alternator is bad. That is the part that is in the end plate that is screwed to the back of the rest of the unit. If you are adjusting the voltage adjustment screw to no avail, then something has failed in the electronic assembly that is in that cap. The electronics are encased in a hard plastic like material and cannot be fixed. Erik's Surplus (https://eriksmilitarysurplus.com/index.html) sells the end plate for $87.50. I just checked it.

If you have someone who can check the rest of the unit, they can check for any disruptions of the armature (shaft) and the field coils. Those are the copper wrapped curved plates that the armature rotates in the middle of. They should be OK.

If you have any doubts which unit you have, look at what he has on his website. If still needing some help, just call him and he can walk you through what you need. Kevin.
Kevin B. Emdee
Star Electric Ordnance (M-series electric parts)
368 Big Oak Trail
Radcliff, KY 40160
1-270-877-0813 (Fax-5042)
Kevin.Emdee@comcast.net
MVPA #530
U.S. Army (retired)
1944 WC-56/1969 M-274A5/1968 M35A2/1968 M-543A2/1961 M-151/1967 M-151A1

11ACRLT
G-First Sergeant
G-First Sergeant
Posts: 131
Joined: Mon Sep 01, 2008 4:49 am
Location: Marine City, MI.

Re: alternator ID

Post by 11ACRLT » Sun Apr 26, 2020 1:48 pm

Kevin,
Thanks for the info. I've been able to ID what alternators I have, 1 is a AMA5102UT, I will have to replace the rectifier assmb and the regulator on this unit because the pin style regulators are not available. The other unit is a 3002AE, regulators are available for this one. Should be good to go once the parts get here.
Curt W Kitter II
'42 MB (sold)
'51 M38
'52 M37 (sold)
'53 M211(sold)
'64 M105A1
'71 M151A2
'72 M35A2C
'72 M561 (sold)
MVPA # 17981
MVCC-MI

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Kurt Lesser
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Re: alternator ID

Post by Kurt Lesser » Sun Apr 26, 2020 2:24 pm

Unfortunately the AMA 5102 alternators have a different voltage regulator than the more common AMA 5104 and they don't interchange. The 5102 regulator connects thru 3 round pins and the 5104s connect thru 4 1/4" blade connectors. I'm not sure if Southern Automotive still sells the regulator for the 5102 beecause of it's age.
Kurt Lesser
US Navy, 1969-1975
M996A1 Ambulance w/M101A3 Trailer
M274A2 Mule
M151A1 Mutt w/M416B1 Trailer
M890 Crew cab

Star Electric Ordnance
G-Second Lieutenant
G-Second Lieutenant
Posts: 518
Joined: Wed Nov 26, 2003 7:52 pm
Location: Radcliff, KY

Re: alternator ID

Post by Star Electric Ordnance » Sun Apr 26, 2020 4:22 pm

Kurt, Erik's sells both the round pin and flat blade end caps. Kevin.
Kevin B. Emdee
Star Electric Ordnance (M-series electric parts)
368 Big Oak Trail
Radcliff, KY 40160
1-270-877-0813 (Fax-5042)
Kevin.Emdee@comcast.net
MVPA #530
U.S. Army (retired)
1944 WC-56/1969 M-274A5/1968 M35A2/1968 M-543A2/1961 M-151/1967 M-151A1

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Kurt Lesser
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Posts: 3779
Joined: Sun May 16, 2004 3:08 pm
Location: San Jose, Ca
Contact:

Re: alternator ID

Post by Kurt Lesser » Sun Apr 26, 2020 6:34 pm

That's good to know Kevin as I have both units on trucks. Thanks.
Kurt Lesser
US Navy, 1969-1975
M996A1 Ambulance w/M101A3 Trailer
M274A2 Mule
M151A1 Mutt w/M416B1 Trailer
M890 Crew cab

Star Electric Ordnance
G-Second Lieutenant
G-Second Lieutenant
Posts: 518
Joined: Wed Nov 26, 2003 7:52 pm
Location: Radcliff, KY

Re: alternator ID

Post by Star Electric Ordnance » Sun Apr 26, 2020 7:18 pm

Kurt, Check out this alternative alternator. Kevin.

http://wolverinetechnologiesllc.com/Alt ... 35M54.html
Kevin B. Emdee
Star Electric Ordnance (M-series electric parts)
368 Big Oak Trail
Radcliff, KY 40160
1-270-877-0813 (Fax-5042)
Kevin.Emdee@comcast.net
MVPA #530
U.S. Army (retired)
1944 WC-56/1969 M-274A5/1968 M35A2/1968 M-543A2/1961 M-151/1967 M-151A1


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