Installing a GM Alternator
in your Samurai
By Figmo
The stock Samurai alternator puts out around 30 amps. That's barely
enough to power the vehicles stock electrical system. Try this experiment
- start your vehicle and let it warm up to operating temperature. As
it's idling - turn on your high beam headlights and listen to what happens
to the idle speed. It slows down just a tad. Now imagine adding more
of a draw to this system - say a winch or a stereo & amp or offroad
lights. Obviously, the stock alternator needs to go. And the perfect
replacement for it is a GM style alternator. These alternators are common
to find, inexpensive when compared to the stock alternator (last one
I purchased cost me $120.00) - and come in a wide range of amperage
outputs (all the way up to a whopping 120 amps).
With the Roadless Gear GM Alternator
Kit, Installing one of these alternators under your hood is literally
a half hour job. And here's how it's done...
First,
disconnect your battery's positive terminal and remove your stock
alternator and the upper and lower brackets that held it on. The kit
includes a new lower bracket but you will be reusing your stock upper
bracket after it has been modified a bit. Go ahead and install the new
lower bracket on the engine block at this time and connect the new alternator
to it. Leave the lower bolt holding the alternator in place alittle
loose so you can swing the alternator up and down.
The stock upper bracket must be slightly modified to clear the larger
body of the GM alternator. This is easily done on a bench grinder. Remove
about 1/8" of material for the lower side of the bracket (the side
that faces down to the alternator). Refer to the picture at the left
for the area that must be ground. As is the case any time you are modifying
a part, work slowly taking alittle off at a time. And keep going back
and test fitting it until you get it "just right". The material
on this bracket is quite soft so it doesn't take much to get it where
it needs to be.
Once you have the upper bracket fitting just right - go ahead and bolt
it in place both on the engine side and at the back of the alternator.
You are now ready to hook up the wiring.
The
wiring for the GM alternator is easy. There are two terminals on the
side of the alternator and one at the back. The kit includes a "pig
tail" connector for the two side terminals. The terminal on the
back on the GM alternator is the output, It is in a similar position
and appearance to the stock Samurai alternator's output. In fact - you
will connect the same wire that went to your stock alternator's output
post to the output post on the GM alternator. The red wire from the
pig tail connector also loops around and connects to this same output
post. This effectively makes the alternator a "one wire" alternator.
This just leaves one wire (the white wire) left to deal with. This
wire connects one of the wires from the big green plug you pulled off
the back of your stock alternator. It is for the "idiot" light
on the dash. Which wire does it connect to? Ahhh - the million dollar
question.
You
see, Suzuki changed the wire colors from year to year. It should be
the white wire with the red stripe on it if you have a 1988. But if
you don't have one of this color - don't worry. It's very simple to
find out which wire on the connector goes to the white wire on your
new GM alternator. Go ahead and cut the big green connector off of the
wire harness and strip the insulation back a bit on the two wires on
the harness. Pick a wire (either wire) and temporarily twist it to the
white wire on your alternator pig tail connector. Make sure it's well
away from anything metal it could short out against. Reconnect the battery's
positive terminal and start your vehicle. Now turn the key off. If the
engine stops - you have the right wire. Go ahead and use the included
butt connector to permanently connect the two together. If the motor
continues to run even after turning the key off - you have the wrong
wire. Carefully disconnect the wire (the engine will stop at this point)
and connect it to the other wire on the harness.
The
only thing left to do at this point is install the included fan belt,
tension it and tighten the bolts on the alternator down. That's all
there is to it. Installation time is less than an hour using common
hand tools and a bench grinder. Once your done - try that experiment
we tried at the beginning of this article again and hear the difference.
Note: under load, at night you may notice the battery light
glow very slightly. This is normal. To function properly the GM alternator
need this bulb to cause some resistance. This is why it glows slightly.
If the alternator fails this light will glow very brightly.
If a high output alternator is to be use I would recommend that the
fusible link be replaced with a fuse. The fusible link protects the
battery from overcharging. I am using a fusible link with a 74 amp alternator
. Also if you are planing on using a 105 amp. Alternator or higher,
I would highly recommend replacing / bypassing the stock output wire
with a new heavier gauge wire from the Alternator output direct to the
battery.
