David :
I went to the local "self-service" junk yard and got the alternator, wiring
harness back past the regulator, and regulator. I think it was from a
'70-ish Mercury Marquis, but the alternators themselves appear to be
mechanically identical from early '60s up through mid-80s. I picked the
car model based only on the location of the regulator, since I wanted to
put the new regulator on the blanking plate next to the old one. I have a
friend with a 84 T-bird, which appears to have the same alternator. I
didn't worry about electical size, on the assumption that anything that
would run an American full size would have plenty for a LBC <g> (I think
Ford's smallest alternator in that time frame was rated 48 amps, which is 2
1/2 times my generator's rating !)
For the pulley, I took my old generator pulley to a machine shop, and had
them bore the hole to match the shaft on the alternator. (The center hole
in the old pulley was badly worn anyway.) I didn't use a key, since the
alternator didn't have a keyway. I think they charged me $10 (in 1982).
This results in the belt being a little hard to get on, as the alternator
body is somewhat larger than the generator was. Depending on the brand of
belt, you may have to take the alternator loose to change belts. (No big
deal, just another step. Makes it tricky to change belts with the engine
hot, though.) Seems to me that I originally did some modifications on the
alternator body (with a hacksaw) to get it a little closer to the engine
block. Since the generator pulley was larger than the alternator pulley,
the alternator turns a little slower, so it doesn't charge as much at idle
as it might. Mine will just about keep up with the halogen headlights and
electric radiator fan at an idle. (I was looking at another car in the
local club the other day, and they managed to buy a new pulley with
apparently the right width and shaft size, but a smaller diameter. If I
ever see Herman, I intend to ask where he got it.)
If I was doing it over today, I would probably try to buy a new pulley that
would accept the 3/4" belt, but be closer to the original alternator pulley
size. When I put on the electric fan (and removed both the stock fan and
the crankshaft extension), I was able to put some flat washers in the
middle of the crankshaft pulley, to reduce it's effective diameter, and
loosen the belt somewhat. (I'm also using a cogged belt from a Cummins
truck dealer that is very slightly shorter than the ones supplied by Moss.
However, I'll never have to change it again !)
For the lower mount, I removed the spacer that normally goes from the
engine front plate to the front generator tab. (Mine was bad, as they
frequently are.) The rear mounting surface of the alternator case was then
cut off to make the pulleys line up (done by eye, with a hacksaw), with the
alternator mounting tab entirely in front of the engine front plate. I
cut a piece of pipe to go inside the bracket bolted to the engine block (so
the bolt wouldn't crush the bracket ears together), then ran a long bolt
through the alternator pivot, the engine front plate, the piece of pipe,
and the rear generator bracket ear. I don't recall the bolt size, but it
was picked to go through the generator bracket without modification. It
was somewhat smaller in diameter than the Ford bolt, but I've never had any
problems with it.
I've since seen kits for sale somewhere (Warshawsky maybe ?) that have an
adjustable lower bracket.
For the upper mount, I straightened out the bends in the original generator
bracket (the one with the long adjustment slot), so it lined up with the
alternator mounting tab. The bolt runs from the rear, through the slot,
and threads into the alternator.
Other changes :
1) The Ford alternator (at least the one I got first) seems to need more
current through the warning light. When I first installed it, I had to rev
the engine to about 2000 rpm before the alternator would "kick in". After
checking a shop manual, I added an 8 ohm 5 watt resistor to the back of the
red "generator light" on the dash. The alternator uses this circuit to
supply field current when the engine starts. Once the alternator is
working, it supplies it's own field current (and the bulb goes out because
there is no longer current flowing through it). My Chevy shop manual also
shows the resistor, even on cars without the idiot light. Another
alternative would be to use a Chrysler 3-terminal regulator, but it won't
operate the idiot light.
2) The output of the alternator is far more than the 30 amps the ammeter is
designed to handle. I added a shunt across the ammeter terminals, made
from two pieces of steel "baling wire" (almost as important as duct tape
for keeping a TR on the road !). The idea was just to keep the ammeter
from banging into the peg after the engine starts. IMO, ammeters are only
useful as relative indicators anyway (is it charging a little ?, is it
discharging a lot ?!), so I didn't worry about calibration.
3) Wiring. I don't recall the exact changes, but I left the original
regulator in place, and still mostly wired. The alternator output is
connected into the A1 terminal, and the wire to the dash lamp is removed
from the old regulator and connected to the new one. The wires to the old
generator were taped up, and left connected to the old regulator. I wound
up having to create a new terminal between the alternator and the old
regulator, since the output wire wasn't long enough to reach. This
terminal is where new high current accessories are connected (headlight
relay, radiator fan relay, electronic ignition, etc.), to avoid running
high currents through the old wiring as much as possible (and also to get
the highest voltage to the new accessories).
It sounds complicated, but I finished the installation in an afternoon,
after getting the pulley machined and the junk yard parts. Other than
having to occasionally clean the contacts on the regulator, it has been
trouble free. (I finally bought a solid state replacement regulator last
year.)
Let me know if I can answer any other questions.
Randall
On Tuesday, February 23, 1999 5:34 PM, David Moag [SMTP:moag@ix.netcom.com]
wrote:
> Randall,
>
> The part that worries me the most about changing to an alternator is how
to
> mount the thing --- and how to find one with a similar pulley size, etc.
How
> smoothly did your Ford ones go in? Do you remember which model(s) they
were
> for?
>
> Thanks,
>
> Dave
>
> > -----Original Message-----
> > From: Randall Young [mailto:randallyoung@earthlink.net]
> > Sent: Tuesday, February 09, 1999 5:21 AM
> > To: David Moag
> > Subject: Re: Re : Heated Seats ???
> >
> >
> > David :
> >
> > FWIW, I've put Ford alternators on my last 2 TR-3's, and been
> > very pleased with
> > the results. The first one was a daily driver in winter in
> > Indiana, where it
> > gets rather chilly (and I didn't have any place to plug in a
> > charger at
> > night). The second car had a bum generator mount when I
> > bought it and, rather
> > than mess with it, I just put on another alternator. That
> > was over 16 years
> > ago, and the alternator is both more reliable, and easier to
> > repair than the
> > old generator. Although my mount is somewhat hokey, it has
> > worked perfectly
> > all these years.
> >
> > Randall
> >
>
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