When I first setup my truck I used an alternator from an 80s IDI F250, it worked fine but didn't have a whole lot of power(75a I think) and I was never very happy with the mount I made for it.
So when that one went out I decided to try to do a little better job.

The one I found is a 90-01-4109, that's the Wilson number but also the same one NAPA uses. It will probably cost around $210 for just a regular cash sale(not through an account). It's 160amp, single wire.

Upper mounts bolt almost perfectly to the stock generator mount. I probably could have added some washers between the alt and mounts but decided to just tighten the bolts for now and call it good


NOTE: the alternator does not come with a pulley, this is one I had laying around the shop.


The lower mount/tensioner required a little engineering but not bad at all. There was already a hole in my motor mount so I simply used a 7/16th bolt with a 1/2 connector nut as a spacer sleeve(you could use pipe, stack of washers or find an entire different spot to anchor the turn buckle).



NOTE: it might seems tempting to anchor the turn buckle to the frame rail but remember the engine is mounted on rubber bushings and can move independently of the frame, that and the frame flexes so the turn buckle must be mounted to the engine or engine mount.

Then just tighten the turn buckle until the belt is tight, connect the positive wire and you're done, no need for a regulator as this alternator has an internal one.
I ran a peice of welding wire directly to my battery, yes there should be a fuse in there but that can be added at a later date when I got back and clean up all the wiring on the truck.
The smaller red wire is the one that goes to the fuse box of my aftermarket wiring kit.
The thick gray wire that goes to the mount is just a ground cable for my jumper cable connector.

There will be 2 small studs on the back of the alternator, just ignore these(wrap in electric tape to be safe).

The one I used is a 90-01-4109, this is a re-manufactured alternator so you will have to turn in a core, chances are you could probably get away with turning in any alternator as a core, but a simple trip to pull-a-part could probably produce an alternator that looks almost identical(check GM vehicles). If not, the core price is like $35.

90-01-4109N is the part number for the same alternator but brand new, this won't have a core charge and is not re-manufactured. I'm not sure how much these cost or what the availability is.

 

What kind of alternator is it? Looks good.

 

Colin, there is a much easier-on-the-wallet alternative, that uses the (gulp) GM 1-wire alternator, which is very inexpensive, and the stock generator mount with a few additional parts from your local hardware store. I would not want to spend that kind of money on an alternator.

If you do a search in our archives, you can likely find the link to the article that has great photos, it was by someone like "57 ranch wagon", I think. Now that I think about it, the link was from the Y Blocks Forever sight, but it was on the FTE site.

It really pains me to admit that I have anything G.M. on my truck, but there it is.

 

I used the GM 1 wire on my ranchero, but I like your idea of using a turn buckle , I'll have to try that.

 

Now dosen't it just make you feel free to admit that?

 

I feel so dirty......

 

This is a GM 1 wire. It's a Delco 21si. Reason for using this one is I wanted more power since I have a winch and two 4D batteries. This is 160amp and the standard GM 1-wire that most people use are 60-90amp. I paid $130 for the alt since I work at a NAPA store.

I didn't look through the application guide for it but it would normally be used for semis/large equipment.

If you go through the Wilson(NAPA's supplier for HD starters/alternators) alternator book this is the highest output one you can get before you start getting into VERY expensive/specialty stuff.

 

When I go on a long trip the GM alternator is the only thing I worry about breaking

 

I was kind of wondering what you needed 160 Amps for. That should do it!

 

I'm a fan of the gm one wire. Nice job on the install....I put one on my 223 when I was having generator problems, but didn't fess up on the forum because Spurredon and a couple others were advising me to keep it stock. Now that I have a cummins engine and a gm transmission. I don't think it matters any more. I have always liked your truck. That picture from the front is nice. I didn't realize it had such nice paint. I will stop in at NAPA next time we visit my fiance's sister and her family and say hi. Happy New Years to any other geeks sitting at home, looking at the FTE site tonight

 

Nice looking install. 160 amps is a lot of juice. How does it behave if you are using a lot less? I could use some more power but I was worried about too much power and over charging the battery. Is my concern justified?

 

It shouldn't be a problem, they have a built in regulator, it will only send what is required.

 

I use the 3G Ford alternator on everything I build now. It is superior to a Delco in every way. I get them from mid to late 90s V6 cars. They do require an extra wire with key on power but how hard is that? Advantages are that even the smallest version is 95 amps and it makes most of that at an idle plus the voltage regulator/brush holder is accessible from the rear without splitting the case. I pay $10 for them at the junk yard.
Here's the large frame version I have on my roadster pickup. Sorry the picture is crappy, it's the only one I have showing the alternator.

 

Thanks! The whole truck's still a work in progress but it's getting there. The paint looks alot better in the pictures too...

Yea if you're ever on the island I'd deffinetly show you the truck, I actually work at the NAPA in Havre, MT(I goto school there) but am back home here every so often.

 

Here's the simple wiring for the Ford 3G.

http://www.bcbroncos.com/3ginstall.pdf