Etype R

GM alt can be picked up for under $80, if you know someone with a welder and some tools you can make a bracket that works. It would have to be cheaper then bringing it to a shop, or selling it at a loss and replacing it.

Plumbrbob

I have had problems with the external regulator, they tend to go bad no idea how to test em jsut R&R and go.

I got sick of that external regulator BS and went to the junk yard to steal the lower alternator mounting bracket and electrical connector off a 85-95 22r/re bought a internally regulated alternator and havent had any issues except when I fill it with mud.

btw you do have to do a little re-wiring I jsut rehooked up the charge wire and used the switched 12v power for the exciter pin which is the upper right pin. thats it 2 wires and it works.

pennywize

had similar problems in my 79, replaced alternator 3 times, regulator twice. tested all wiring, (i thought) couldnt make it work. finally grabbed an internally regulated alternator and bracket from a 1986 and it worked fine after that.

seanmearse

Pennywize, I'm not forgetting about you. The both of you have a great idea. Can you explain more, or even better maybe some pics of how the wiring is set up?

Plumbrbob

I dont think pics would say anything I hope I can get my words across.

to do a 85-95 alternator mod to a pre 84 block you need the lower alternator mounting bracket from a 85-95 the upper is fine some massaging is required.

Next you need a 85-95 alternator with an internal regualtor.

To get it to work you need to hook up the charge wire as usual to the single post.

All that is required to get it to start a charge is to send 12v to the exciter pin. the 85-95 alternator has 3 pins its different then your pre84 alternator whcih has 4 or 5 pins.

What I did was hooked up spade connectors to all 3 pins then added 12v to each wire individually until my multimeter showed a charge of 13V or more I then mark that wire as the exciter.
If you grab an old connector out of a salvage rig you can re-pin the connection so its water tight.

I used my multimeter to find the keyed 12v power wire off the old alternator connector by turning the key on and off until i found it. then I spliced in and repinned the connector. the other 2 i have no idea what they do I have never had a problem 2 years going with this setup except when I pack the winding with mud LOL

I ran with a spade connector to the back of the alternoator and a butt splice for some time till I got around to taking it all apart and repinning the connector. they sell a speical repin tool at the auto store.

I feel your woes and when you cant charge its really pisses me off I feel like throwing my truck away I know your pain the old set up gave me so much greif the newer alternators are simple one wire to charge one wire to excite power is supplied to the exciter and no charge bad alternator plain and simple

good luck bro

btw did you replace the external regualtor they are a spendy new I always grabed used ones that were 20+ years old

seanmearse

That sound like a plan. what gauge wire did you use? also, how much "massaging" of the upper bracket is required?And then do you just ditch the regulator?

Edit- Are you still running this setup?

Plumbrbob

i just matched the same gauge wire from factory dont remember which one it was. my massaging technique was a hammer i hit it up or down to make it work it was barely off. their are slightly different upper brackets I saw no harm in giving it a tap. grabbing the newer upper bracket would be a good idea too incase you never know.

my regualtor is still installed but not hooked up I just remembered I had to run a new charge wire to ditch the regulator. So yes I ditched the old.

just remember all you need is charge wire that is hooked up and a 12v exciter wire that is controled when you turn on the key the wiring can be as complex or hill billy as you choose to live with.

Plumbrbob

yes this is in my truck now and i have 14.4 on the gauge every day I go to work. I DD this beast LOL

seanmearse

Sounds good. Im going to snatch up an alternator and the brackets in the morning. Wish me luck...

pennywize

i dont have my '79 anymore, just got rid of it a couple months ago, im planning switching a new alternator onto my 82 i have now though.

plumbrbob had a good write-up.
i ran a 6 guage wire from the alternator to the battery though with an 80 amp fuse inline. my main charge cable needed replaced and i had a spool of 6 guage laying around so i used it. i also used the factory alternator plug from the '86 and wired it up accordingly, i dont remember what wires were what, just used the wiring diagram i had.
my conversion worked perfect.

seanmearse

Wasn't ignoring you bro. Just a little po'd at this thing and didnt want to wait around on it getting stuff fabed up and waiting, the internal conversion sounds a little faster, so im gonna run with it.

Plumbrbob

I also recalled that the procedure requires to remove some of the motor mounts bolts and you might want to remove a few things to make room to work I took my radiator out to make things easier. I also remember the old upper bracket not working out at all and I had to peel off the power steering pump to get the the mounting holes for the newer style upper bracket.

here is a pic of my motor it has around 10,000mi on it as you can see newer style alternotor on a old pre 84 block.

seanmearse

So you used the newer upper bracket too? One more, what did you use for the exciter wire, as in, what did you tap in to?

Plumbrbob

thats right I had to run a new charge wire to the battery with a fuse.

Its been a while well couple years now its plug and play now. I never had a diagram (still wish i knew what the other two pins do)

I do remember if you hold the alternator looking at the back three pins the upper right is the exciter "I think" LOL

Plumbrbob

yea i had to use the newer upper bracket the one that allows belt tension.

I tapped into the original exciter wire from the old alternator connector.

hope i was clear enough I am better at doing than explaining LOL

seanmearse

Man, I hope I can handle this. what would you recommend for the fuze size?

Plumbrbob

pennywise said he used a 80 amp and I dont remember. It seems to me that these newer alternators put out 80 amps vs. the older style which is 60amps

IDK if you can handle this?

To me its simple nothing but time. everything is bolt on, some stuff needs to be removed to get to the moutning bracket bolts its tight to work in and its typically greasy mess in that area cause of the ps pump and dip stick.

some tricks I remember is get the rad and clutch fan out of the way its easy to remove and install no biggie makes thngs go faster.

peel the ps pump off try not to fully remove it leaving the lines intact this will speed things up by keeping the fluid from draining everywhere.

For the lower bracket just remove the bolts needed to slip the bracket assembly in, it slips in between the block and the motor mount bracket, if you have a hoist use it or a jack with a 4x4 on the oil pan that will ease in this procedure by not putting any weght on that motor mount

the lower rad hard line will give you grief I remember peeling it away but leaving the upper rad 90 rubber hose attached therefore leaving it dangling jsut so i can get that stupid spacer and bracket in.

I am sure you may now need a new belt what size idk i have LCE underdrive pulleys

If you dont have a wiring diagram just use the back yard method of hooking up all the pins to long leads with the truck running just have one lead at a time connected to a constant 12v power from anywhere. if your multimeter reads 13 or better you have a charge and you have located the exciter pin.

Its a full on bolt up mod with some wiring involved good luck hope all goes well

seanmearse

Thanks man. I just had a thought too, the older alternator has to have an exciter wire too, right? how else would it know to kick on? this is perplexing, i hate wiring. I can do it, just despise it. Ill let you know how it goes. Oh, also, the alternator in the 84 was listed as a 40 amp. That doesnt sound right, does it?

pennywize

not sure about 84 but yes the older alts were 40 amp. the 86 i used was 60 amp.
removing the fan and related parts would make it easier but not required. i fried my 60 amp in a mud pit one night, had someone bring me a new one and i replaced it in the parking lot of the pizza place without removing any radiator hoses or the fan. it kinda sucked though.

seanmearse

Pennywize, do you remember which wire was used for the exciter on the back of your alternator and which wire is the existing one it connects too?