AMC alternators: 
Motorola to Delco Alternator Interchange

delco-amc-interchange.JPG (47856 bytes) 

Above is a original 1966 1/2 thru early 1972 AMC V8 Motorola alternator bracket. The "new generation" AMC V8's used Motorola with several different AMPs (depending on options, fleet package, police, taxi, ect) on 290V8, 343V8, 360V8, 390V8 and 401V8. AMC changed the bracket.....when they went to Delco in early 1972. The Motorolas are difficult to find 40 years later, and expensive when found, and they usually still suck like they did in 1960s, and rebuilt. Sometimes get lucky at Auto Zone or O'Reilley, Parts Zone, NAPA however, but I highly recommend unless you building a concourse level car, to make the switch to Delco; they are easy to find, checp and plentiful and have the voltage regulator inside them. 

People ask me about this all the time, as most of my AMCs from my 68 Rebel convertible "Machine" 401 to the 71 SC/360 have this conversion. In Houston, there is a place I have dealt with for this for over a decade call Metro Auto Electric on Harwin Avenue. Chances are you probably have a automotive electronic place in your town listed in the yellow pages, or simply ask folks in your area AMC club or fellow car buffs at cruise nights and car shows. It is a real simple interchange and these alternators are superior to the original Motorola ones AMC used on many of our cars.  Thanks to Mike Wilson of the Hoosier AMC
Club for his article, ya'll save this as it is a FAQ!


This is one interchange article with photos courtesy fo WSC Motorsports 

This is another below:

The Delco 10si Alternator And Your AMC
By Michael Wilson

Retrofitting a Delco 10si Alternator on your AMC is a pretty straight
forward swap if your armed with a little knowledge. Some will ask why? The
parts for the Motorola are getting a bit expensive for one thing. The
Motorola puts out at best 40 Amps while the Delco 10si puts out a steady 65
Amps at a much lower engine RPM. The Delco is inexpensive, easy to wire, and
self regulated! You will need a Delco Alternator and new pig tail plug in
for a GM alternator. I tell the guys at the parts store I need an alternator
for a 1980 AMX with a 258 since AMC used the Delco on newer 6 cylinder cars.
The parts store should have the new pig tail as well.

When you compare the Delco to the Motorola the first thing you will notice
is that the mounting leg is much thicker on the Delco-2" versus the 1 1/16"
on the Motorola. The mounting hole diameter is smaller on the Delco as well.
If you have a V-8 290-401 you can modify the Delco to fit your existing
mounting brackets by carefully cutting down the mounting leg with a good
hacksaw and finishing up with a file and some light sanding. You will need
to drill the hole out larger as well. This is the easiest way to mount the
Delco to a V-8 but not the only way by any means. AMC used several different
mounting brackets on the V-8 over the years. Most of these can be modified
to accept a Delco right out of the box if you don't want to modify the
alternator as outlined above. The best set up is the late model brackets
that started showing up around 1976 or so. This set up uses an
adjuster/slider bar that mounts to the oil pump housing and a triangular top
mount that attaches to the water pump. Be aware that some of these top
mounts use two 5/8" spacers between them and the water pump while others
have this area cast into the water pump. The reason for spacing the top
bracket out from the water pump is to give you room too attach the heater
hose to the water pump. You may still need to drill the Delco mounting leg
to mount it! An alternative would be a threaded insert in the head to reduce
the size of the bolt required. You will also need in most cases to make a
spacer to go between the head and the alternator. I used 3/8" galvanized
water pipe to fashion mine from and then painted it black.

If your doing a 6 cylinder car 199-258 with the alternator mounted on the
drivers side it's much easier than the V-8 swap. Remove your Motorola and
the "F" bracket that mounts it too the engine. Remove the "F" bracket from
the alternator and put it in a vise. Use an air chisel and split the bracket
into two halves. Now set the needed mounting space for the Delco and
re-drill your mounting holes that attach the alternator to the block. If you
do not want to modify your existing "F" bracket you can buy one for GM
applications from Jegs or Summit. The Chevy small block thru 1968 bracket is
the one you need. You will probably need a few washers to use as spacers to
get a tight fit between the alternator and the end of the bracket. You will
need to loosen your top slider mount and move it up slightly to get the
Delco mounted.

Now after you have went through all the trouble to mount your new Delco
Alternator you want to wire it up. First unplug your regulator and tape up
the wiring harness where it plugged in. Now attach the original charge wire
from your wiring harness to the charge stud on the back of the new Delco
unit. Solder a ring terminal on to the large red wire on your new GM pig
tail connector and attach it to the charge stud as well. Tighten up the
charge stud nut and plug the pig tail into the alternator. You have one wire
left to hook up. What your looking for is the wire from your old alternator
that has power when the key is on. This is usually the orange wire from your
old alternator. To check this turn your key to the on position and check
with a test light. The test light should come on and your alternator dash
light should glow when the test light is attached. This is the only wire you
need to cut! Snip it and solder it to the white wire on the pig tail and
tape up all the other loose connections from the old alternator and your
done!

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