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lostforawhile
01-03-2009, 08:05 PM
I just removed my dead ac compressor and it's associated boat anchor, it looks like the alternator will fit right into the ac bracket,all i need to add is a universal adjusting arm. If this works I can cut off the entire bottom half of the bracket,and still have four mounting holes. i happen to have a brand new alternator in my "junk" still in the box, so i'm going out in a bit to see if it fits. it shouldn't require much horsepower to turn if the field is disconnected, I would just need to build a switching system .

labeledsk8r
01-03-2009, 08:47 PM
the question is why.... why load more crap into the engine bay... alts hardly fail and if it does it normaly gives some warning to it... not to mention you can get a good 2 hours of drive time out of a good batt without an alt as long as your not blasting music or useing alot of electrical...id say slap the new alt into your car and then not worrie about it

lostforawhile
01-03-2009, 08:51 PM
the question is why.... why load more crap into the engine bay... alts hardly fail and if it does it normaly gives some warning to it... not to mention you can get a good 2 hours of drive time out of a good batt without an alt as long as your not blasting music or useing alot of electrical...id say slap the new alt into your car and then not worrie about it it's just an idea is all and some people who have huge stereos might want the extra one also. just something i was looking at after removing the bracket. also if there was a way to add an idler pulley where the alternator is now, it could just be moved up front and much eaisier access

labeledsk8r
01-03-2009, 09:10 PM
moveing it up front might be a good idea... it is lower so water and such might get on it easyer.. why would you need an idler pully? each accesory is on its own belt

lostforawhile
01-03-2009, 09:12 PM
moveing it up front might be a good idea... it is lower so water and such might get on it easyer.. why would you need an idler pully? each accesory is on its own beltalternator and water pump share the same belt

lostforawhile
01-03-2009, 09:34 PM
here's what it looks like on the bracket, with the alternator all the way to one side it sticks out past the ac pulley,but there is plenty of adjustment, just have to get the spacers right. as fas as the bottom it almost lines up with the adjuster where the bolt would go through,but not quite. so a little fabrication needed. it's completly able to be done, I see no reason why it couldn't be. the last obstacle is the alternator pulley, the ac has three ribs,and the alternator has five, just have to source a three rib pulley somewhere. http://i220.photobucket.com/albums/dd158/lostforawhile/S4020166-2.jpg
http://i220.photobucket.com/albums/dd158/lostforawhile/S4020168.jpg

labeledsk8r
01-03-2009, 10:31 PM
forgot about the waterpump lol damn im allready getting used to the civic running the water pump off the timeing belt... soon i will have forgoten everything about the 3g

AccordB20A
01-04-2009, 01:20 AM
i was thinking of doing the same on my b20a since i keep blowing them, two alts should be able to keep up with large bass hits :)but i dunno if i can be bothered maybe ill go try it on my b18 tomorrow i would laugh if i can get it to work.

If i can get it to work and a belt long enough to fit properly ill probably install it, hell maybe ill install a battery at the back specially for the sound system and run it off a totally independing charging system, Ill hook up the catalic converter light in my dash as a 2nd battery light, WIN mean i might do that.
More weights but hey i dont care

Ichiban
01-04-2009, 10:46 AM
the last obstacle is the alternator pulley, the ac has three ribs,and the alternator has five, just have to source a three rib pulley somewhere. http://i220.photobucket.com/albums/dd158/lostforawhile/S4020166-2.jpg


Why should the pulleys be a problem? Does the A/C bracket line up the alternator with the inside (large) pulley, or the small one towards the framerail? If you line up with the same pulleys to begin with, you'd just be simulating the system that the 1st and early 2nd gen cars had, Alternator in front and water pump in the back. No idler needed.

lostforawhile
01-04-2009, 01:04 PM
Why should the pulleys be a problem? Does the A/C bracket line up the alternator with the inside (large) pulley, or the small one towards the framerail? If you line up with the same pulleys to begin with, you'd just be simulating the system that the 1st and early 2nd gen cars had, Alternator in front and water pump in the back. No idler needed.no i mean the belt for tha ac is more narrow, it's a ribbed belt, the ac has three and the alternator has five. there plenty of area to move the alternator back and forth on the bolt to get the pulleys lined up,some heavy duty washers would make it work fine,myself i would have to machine a spacer for each side. that bolt i pulled out of junk is actually an 81 civic head bolt lol. if you moved the alternator from in back you would still need an idler for the water pump. water pump and alternator share one belt, power steering is the outside non ribbed belt, and the other belt is the ac

Ichiban
01-04-2009, 01:16 PM
no i mean the belt for tha ac is more narrow, it's a ribbed belt, the ac has three and the alternator has five. there plenty of area to move the alternator back and forth on the bolt to get the pulleys lined up,some heavy duty washers would make it work fine,myself i would have to machine a spacer for each side. that bolt i pulled out of junk is actually an 81 civic head bolt lol. if you moved the alternator from in back you would still need an idler for the water pump. water pump and alternator share one belt, power steering is the outside non ribbed belt, and the other belt is the ac

I see what you mean about the 3/5 ribbed belt, but what I meant was, if you stayed aligned on the inside pulley, you could get away with using all the same parts, even the same belt probably.

lostforawhile
01-04-2009, 01:27 PM
I see what you mean about the 3/5 ribbed belt, but what I meant was, if you stayed aligned on the inside pulley, you could get away with using all the same parts, even the same belt probably.i'll look at some honda pulleys at the yard next time i'm there, just to see what there is, chances are if i find something it would probably fit on the shaft, i've found a lot of honda pulleys interchanable over the years. you other option is to install a larger alternator with this setup, all you have to do is find one that rotates in the correct direction, swap a pulley, nearly anything would fit in there. i really wondered about taking the ac clutch and pulley off and seeing if it could be fitted to an alternator, that way you could have a back up that frees spins unless you engage it.

Ichiban
01-10-2009, 09:40 PM
I'd actually like to go with an AC-Delco one wire alternator, but for some reason the ECU for the B20A needs a wire from the alternator for some purpose. Does anyone know how to fake the ECU into thinking a 4 wire Honda alternator is plugged into it?

AccordEpicenter
01-12-2009, 05:50 PM
I had this idea about 10 years ago when i was running a high powered stereo, what i ended up doing was getting a rewound alternator. The rewound one is good for 140 Amps when cold, but you must have the engine turning about 1750rpm for max output. Stock is about 60 amps so right there youll make more than 2x a stock unit

lostforawhile
01-17-2009, 10:08 PM
I had this idea about 10 years ago when i was running a high powered stereo, what i ended up doing was getting a rewound alternator. The rewound one is good for 140 Amps when cold, but you must have the engine turning about 1750rpm for max output. Stock is about 60 amps so right there youll make more than 2x a stock unitwell the reason i was looking at this,was to possibly attach the AC compressor clutch to one,as a backup,the original is so hard to get to, if i was on the road somewhere,i could flip a switch and engage the back up if needed until i got back home. i think as far as weight i could cut almost half of that ac bracket right off. i really would have liked to have found something like an early honda one or something like a metro one,much smaller and lighter and plenty of emergency power. i just happened to have this one.

2oodoor
01-18-2009, 04:42 AM
intreguing idea

For those that want one, may as well have another battery too I guess.
I can tell you work with small aircraft, you always are thinking of being out there somewhere in time of need.
I like the USDM alternator idea too, just using one of those though.

MessyHonda
01-18-2009, 09:21 AM
i need one...my alt does not charge at idle

cygnus x-1
01-18-2009, 12:08 PM
I used a Nippon Denso alt. out of a Toyota for my diesel Suzuki project. Most people use Delcos because of availability but I found plenty of NDs at the junkyard. The NDs are smaller and plenty easy to wire up so I used one of those. If you look around they come in lots of different clocking configurations too.

C|

Hauntd ca3
01-20-2009, 12:42 AM
i'd go wit the denso alt as well.
they are prob one of the better ones out there

lostforawhile
01-25-2009, 02:02 PM
looks like i'll have to move it to the front, the fuel bowl for the SU sits right over it, and it's a bottom outlet,one small leak and instant fire. i think i can just run a longer v belt around the crank pulley the water pump and the alternator, seen v belts longer then that before. it will mount pretty easy to the ac bracket.

lostforawhile
01-26-2009, 04:19 PM
ok the alternator is moving to the front,have it all figured out,but i need some suggestions on finding a ribbed pulley that matches the one on the ac compressor, only issue i haven't figured out yet.

cygnus x-1
01-26-2009, 09:51 PM
ok the alternator is moving to the front,have it all figured out,but i need some suggestions on finding a ribbed pulley that matches the one on the ac compressor, only issue i haven't figured out yet.


You want a pulley the same size as the one on the compressor? That won't give you the right speed for the alternator. Alternators usually spin much faster than the other accessories. Since the AC groove on the crank pulley is smaller than the alt/water pump groove, you actually need a smaller pulley on the alternator as well to keep the ratio the same.

Or do you mean matches the number of ribs? As long as the alt pulley has more ribs than the belt it should be ok. You can use a 4 rib belt on a 5 rib pulley.

C|

mushroom_toy
01-26-2009, 10:52 PM
If I was you instead of an alternator....I would put a belt driven compressor on there. :) then you could pump up tires, use tools, etc, etc. Lots of jeeps and lifted trucks with em but not many cars if any. :)

lostforawhile
01-27-2009, 04:04 PM
If I was you instead of an alternator....I would put a belt driven compressor on there. :) then you could pump up tires, use tools, etc, etc. Lots of jeeps and lifted trucks with em but not many cars if any. :)
i would consider that but it sucks horsepower. maby for a future idea. what i figured out is a 91 civic alternator pulley is the exact match for the keihin belt. the alternator even looks the same although slightly smaller. i think it's still 68 amp though. it's going to be pretty easy to do this conversion. the top of the alternator fits on the top of the ac bracket with spacers on the bolt, the bottom i'm cutting off the slotted cast in part on the bracket,since it doesn't match up. i'm going to modify one of those universal alternator arms for small blocks. this would actually be a pretty easy swap for anyone who might want to move the alternator.i will do a full write up.

lostforawhile
01-28-2009, 04:12 PM
http://i220.photobucket.com/albums/dd158/lostforawhile/S4020258-1.jpg

lostforawhile
01-28-2009, 07:36 PM
ok going out in a bit to bolt on the plate so i can see how far the pulley has to move to line up. i have a pulley but it's from a different car, the grooves line up but the center is totally different. the auto electric place here had a drum full of different pulleys. thinking of making a center with the correct size hole, pressing it into this pulley center, then welding it to the existing pulley. the grooves are right,but not the center. the 91 pulley will fit,but i couldn't find just a pulley. i used one of these for the alternator arm, http://www.streetperformance.com/ART/PRODUCTS/100489/9851_large.jpg
i cut it off just behind the slot, rounded the end,then drilled a 29/64 hole in the end behind the slot. the adjusting slot on the ac bracket won't line up with the alternator,so the hole on the arm had a bolt that goes through it,this bolt bolts through the ac adjuster slot. the alternator adjuster bolt goes through the slot in the arm,then when it's tensioned correctly,both bolts will get tightened. this allows the use of the existing adjuster slot on the ac bracket. looks to be plenty of clearance back there. i believe the alternator will be able to be removed or installed by removing one fan from the radiator.i'm taking out the PS pump during the install,just because it's much eaisier to install the brackets.

lostforawhile
01-28-2009, 07:46 PM
http://i220.photobucket.com/albums/dd158/lostforawhile/S4020259.jpg

Ichiban
01-29-2009, 01:52 PM
I remember seeing the B20A5 with the alternator up top and front. I wonder how similar the bracket would be from that?

lostforawhile
04-19-2011, 05:41 PM
Ok a long awaited update, I ended up with a civic Obd 2 alternator, it's smaller, lighter, and puts out more amps, I'm using the 70 amp one right now, but later it's an easy switch to an SI 90 amp, I'm still going to do the backup, but run 2 civic ones. I'll use a simple single pole double throw relay to switch the fields, at the moment I have a gutted factor alternator with just the case, bearings and pulley, to act as an idler pulley for the water pump, I wanted to put the belt on to check the alignment, but after turning the house upside down, I just can't find the new one, hence my signature. it's possible it may have to move slightly away from the engine, which will require some machining on the ac bracket. I built the harness, mocked it up, hung the alternator, then discovered I was sent the wrong alternator plug. It never ends.

http://i220.photobucket.com/albums/dd158/lostforawhile/IMG_1848.jpg

http://i220.photobucket.com/albums/dd158/lostforawhile/IMG_1850.jpg
http://i220.photobucket.com/albums/dd158/lostforawhile/IMG_1851.jpg
http://i220.photobucket.com/albums/dd158/lostforawhile/IMG_1844.jpg
http://i220.photobucket.com/albums/dd158/lostforawhile/IMG_1847.jpg
fail!
http://i220.photobucket.com/albums/dd158/lostforawhile/IMG_1845.jpg

lostforawhile
04-19-2011, 06:46 PM
I still don't think you can run both at one time, in my setup it's one or the other, the problem with both running, is you end up in a feedback loop with two voltage regulators, if you were to use an external regulator and wire it to slave both alternators together, it would work fine, like using two batteries in parallel, but with two independently operating regulators it won't work. with the field shut off on the backup alternator the amount of drag on the engine should be very little, there were some of those gas saving forums that tested the amount of drag, and with the alternator disconnected the fuel mileage went way up, even with it free wheeling. it's a little weight penalty, but with the smaller odyssey battery, and the nearest town 40 miles from here, I'm out of comfortable reserve range. With this setup, it's flip a switch and the backup is online

Ichiban
04-20-2011, 01:36 AM
I stuck the alternator up front on my b20a

A18A
04-20-2011, 03:13 AM
If I was you instead of an alternator....I would put a belt driven compressor on there. :) then you could pump up tires, use tools, etc, etc. Lots of jeeps and lifted trucks with em but not many cars if any. :)
ha that's a pretty cool idea!! i really like it lol


i would consider that but it sucks horsepower.
That wouldn't be a problem unless it doesn't have a clutch or you like using tools while driving?

w261w261
04-20-2011, 06:49 AM
OK Lost, when you get done with this it's time to consider a project where you can really wring out your skills........a HYBRID 3G! Out with the rear seat, in with a bunch of Li-I batteries, and (ahem) a bit of mod to the drivetrain. Or even better, skip the batteries as you're more of a mechanical guy, and set up a flywheel energy storage.

lostforawhile
04-20-2011, 01:11 PM
OK Lost, when you get done with this it's time to consider a project where you can really wring out your skills........a HYBRID 3G! Out with the rear seat, in with a bunch of Li-I batteries, and (ahem) a bit of mod to the drivetrain. Or even better, skip the batteries as you're more of a mechanical guy, and set up a flywheel energy storage.

no hybrids for me, just a 25 year old car with no emissions, it's going to destroy the entire world with it's horrible pollution lol. I don't like electric cars, i'm an engine guy.

w261w261
04-20-2011, 03:57 PM
no hybrids for me, just a 25 year old car with no emissions, it's going to destroy the entire world with it's horrible pollution lol. I don't like electric cars, i'm an engine guy.

Well then its time for the energy flywheel. Porsche is taking orders for an $800k race car with one.

dieselgus
04-20-2011, 05:16 PM
Personally I do like the alt up front like that for cooling purposes. Only thing I would add is a heatshield on the manifold side to keep heat down to a dull roar on it. From a maintenence standpoint it would be a helluva lot easier to change as well.

As to a second one in the Oem location to be switched to, I dunno. Lotta work for a low failure item to make sure there is a redundant in place. Like one poster suggested, stick a compressor back there and use an AC clutch on the pulley end. On demand air would be a nifty addition to have on board, and you could probably get some decent CFM happening. Put an "M" coupler in the engine bay and plumb one to the rear just for shits and giggles.

lostforawhile
04-20-2011, 05:27 PM
Personally I do like the alt up front like that for cooling purposes. Only thing I would add is a heatshield on the manifold side to keep heat down to a dull roar on it. From a maintenence standpoint it would be a helluva lot easier to change as well.

As to a second one in the Oem location to be switched to, I dunno. Lotta work for a low failure item to make sure there is a redundant in place. Like one poster suggested, stick a compressor back there and use an AC clutch on the pulley end. On demand air would be a nifty addition to have on board, and you could probably get some decent CFM happening. Put an "M" coupler in the engine bay and plumb one to the rear just for shits and giggles.
the main reason I want the backup, is location specific, it's on average 40 miles to any decent size town here, on back country roads, mostly unlit, I have 27 minutes reserve on the Odyssey battery, that's not enough of a reserve to be comfortable with, the only places to go in the event of a breakdown are tiny towns that are pretty much shut up at night, for example, if you were to leave Valdosta heading home, and not have enough gas, the nearest station open after 10 pm is 38 miles away. Thats how much SOL you would be if your alternator quit at night, as they usually quit at the most inconvenient time, the engineering on it is simple, you bolt the pulley from a stock alternator on to the civic one, and it takes the place of the factory one, with the OBD2 alternators, you just have to hook up the small black and yellow wire and it charges, disconnect it, and it shuts off and free wheels, remember something has to be in place where the factory unit is, so it acts as an idler for the water pump belt, switching the two alternators is very simple with a single relay

lostforawhile
05-01-2011, 01:19 PM
Ok the ac belt won't fit, too big, i've swaped in several belts and it looks like i'm going to need a 3338K4 thats an autozone part number but will cross reference, i'll try to get some pictures, it looks like the belt is misaligned slightly, so i'm going to machine off apx 1/8 on one side of the AC bracket, so the alternator can move slightly towards the fender

lostforawhile
05-01-2011, 08:58 PM
ok the alternator needs to move over slightly to line up the belt, the issue is the arm is hitting the alternator adjuster arm, I thought about machining the bracket, but it looks to be easier to machine the case itself, you can probably do this yourself with a grinder if you had to, I already found enough shims to line up the top bracket, I'll measure the shims and make a single piece adapter

http://i20.photobucket.com/albums/b205/moultriemanicmechanic/aug262009download519.jpg
http://i20.photobucket.com/albums/b205/moultriemanicmechanic/aug262009download520.jpg

lostforawhile
05-02-2011, 04:18 PM
Ok a lot more is finished,

first is the spacer, this is the spacer next to the shims I used to get the measurement

http://i20.photobucket.com/albums/b205/moultriemanicmechanic/aug262009download531.jpg

center drilling the raw material making the spacer

http://i20.photobucket.com/albums/b205/moultriemanicmechanic/aug262009download528.jpg

http://i20.photobucket.com/albums/b205/moultriemanicmechanic/aug262009download525.jpg

this is what I machined to make the arm fit, I used a plastic bag to keep chips out of the alternator

http://i20.photobucket.com/albums/b205/moultriemanicmechanic/aug262009download521.jpg

you can also put the arm on the other side and use a spacer

http://i20.photobucket.com/albums/b205/moultriemanicmechanic/aug262009download523.jpg

http://i20.photobucket.com/albums/b205/moultriemanicmechanic/aug262009download524.jpg

http://i20.photobucket.com/albums/b205/moultriemanicmechanic/aug262009download526.jpg

this is the fuse block for both alternators, I have to swap the fuses with 70 amp fuses

http://i20.photobucket.com/albums/b205/moultriemanicmechanic/aug262009download522.jpg

still have to finish polishing

http://i20.photobucket.com/albums/b205/moultriemanicmechanic/aug262009download527.jpg

1813mdw
05-02-2011, 06:53 PM
lookin good, lost. do you have an exact length on your belt? i can prob find it at my work tomorrow

lostforawhile
05-02-2011, 06:56 PM
lookin good, lost. do you have an exact length on your belt? i can prob find it at my work tomorrowi've got one that fits I'm just using a duralast 338K4 right now, later I'll swap it to a good belt, but this one should work, I think it's the right length, tomorrow i'll weld a heavy washer on the adjuster bracket where the arm bolt goes through, so the only adjustment is at the bottom like the AC, and I still need to make the tensioner

1813mdw
05-02-2011, 07:03 PM
do you happen to know how much the new alt weighs w/bracket compared to the oem alt/bracket?

lostforawhile
05-02-2011, 07:06 PM
do you happen to know how much the new alt weighs w/bracket compared to the oem alt/bracket?

I need to weigh it again, but I think it's two pounds less, it also has a higher output, I can also swap in an SI alternator, I'll have to swap the front case now, but it's 90 something amps, I didn't want the weight penalty of the second one, but with the situations i'm likely to drive in, it's pretty much a necessity. You do not want to get stranded in the middle of nowhere here, or you'll be spending the night in the car, i'm not counting the weight of the AC bracket, The original brackets don't weigh much, I wish I could get that AC bracket cast in aluminum, eventually I might, I have friends who pour aluminum

1813mdw
05-02-2011, 07:10 PM
I need to weigh it again, but I think it's two pounds less, it also has a higher output, I can also swap in an SI alternator, I'll have to swap the front case now, but it's 90 something amps, I didn't want the weight penalty of the second one, but with the situations i'm likely to drive in, it's pretty much a necessity. You do not want to get stranded in the middle of nowhere here, or you'll be spending the night in the car

this seems like alot better option than the legend alt which weighs a ton more than our stockers. i may need to buy a bracket from you in the future:stick:

lostforawhile
05-02-2011, 07:15 PM
this seems like alot better option than the legend alt which weighs a ton more than our stockers. i may need to buy a bracket from you in the future:stick:

I didn't modify the stock bracket at all, I just modified the arm on the alternator, I wish I knew someone who laser cut, as I could make these adjuster arms, since both ends will be fixed, it doesn't need the slot, it uses the adjuster slot on the AC bracket. I can make the spacer bushing very easy, takes about ten minutes. for the arm now, it's a cut off Mr. Gasket universal arm.

lostforawhile
06-22-2012, 08:01 PM
Alternator is in!!

upper pivot bracket
http://i20.photobucket.com/albums/b205/moultriemanicmechanic/alternatorinstalled007.jpg
belt tensioner washer, you tighten the 7/16 bolt up from underneath,and it pushes on the washer and tightens the belt,then you tighten the tension bolt
http://i20.photobucket.com/albums/b205/moultriemanicmechanic/alternatorinstalled005.jpg
back of tensioner washer
http://i20.photobucket.com/albums/b205/moultriemanicmechanic/alternatorinstalled006.jpg
http://i20.photobucket.com/albums/b205/moultriemanicmechanic/alternatorinstalled004.jpg
http://i20.photobucket.com/albums/b205/moultriemanicmechanic/alternatorinstalled003.jpg
http://i20.photobucket.com/albums/b205/moultriemanicmechanic/alternatorinstalled008.jpg
terminal block passenger side inner fender
http://i20.photobucket.com/albums/b205/moultriemanicmechanic/alternatorinstalled002.jpg
alternator cable end,cable is run in firebraid
http://i20.photobucket.com/albums/b205/moultriemanicmechanic/alternatorinstalled001.jpg
I'm working on a heat shield it will get covered in that mica based insulating sheet
http://i20.photobucket.com/albums/b205/moultriemanicmechanic/alternatorinstalled009.jpg
distribution block on firewall
http://i20.photobucket.com/albums/b205/moultriemanicmechanic/550707_10151063715422018_1695847937_n.jpg

I'm probably going to put a functioning alternator back where the factory one was,just electrically disconnected except for emergencies, I've found out from the high milers that an alternator with no field operating has almost no effect on performance and an almost negligible effect on the engine, I don't like one working there mainly because the fuel bowl is directly above it. It's pretty simple to use a contacter and a relay to switch between one or the other. If it's electrically dead and gets fuel in it there is no ignition source. It would be nice to have the backup at the flip of a switch if the primary one fails, if you were in the city it would be no big deal,but out here it can be a long way home if you are stranded. It's a little weight penalty but worth the safety factor

2oodoor
06-23-2012, 04:06 AM
I don't understand it but it is pretty cool stuff all the same!
You have a 4 in 1 header? that thing looks wicked:thumbup:

lostforawhile
06-23-2012, 07:31 AM
I don't understand it but it is pretty cool stuff all the same!
You have a 4 in 1 header? that thing looks wicked:thumbup:


cliffs:
well basically I used a 98-2000 civic OBD2 alternator,because I had to move the alternator, and the pulley is an exact match for the AC compressor groove in the crank pulley,the original one sat directly below the fuel bowl on one of the carbs, since they are a bottom outlet fuel bowl with a rubber hose, that didn't look very good, one leak into the alternator and you have a fire. I took a burned out alternator and gutted it, except for the case, bearing and pulley, and that's my idler pulley where the original alternator was. Since I know that a disconnected alternator isn't much more drag then the idler pulley itself, I may use a functioning one there,but disconnected,except for emergencies, EG. slight weight penalty vs 40 mile walk home in the dark.

lostforawhile
06-23-2012, 09:54 AM
interesting, I found out that in order to shut off the civic alternator while running, you not only have to disconnect the field wire,but the warning light indicator wire, I'm assuming the indicator bulb is feeding voltage back across the bulb filament to the regulator, since the factory alternator has two wires supplying power to the regulator both of them plus the warning light wire will need disconnecting. it's pretty simple with some basic relays.

POS carb
10-01-2012, 11:17 AM
I know it's a bit late but....
wouldn't a secondary battery be a better alternative?
You could have a 2nd battery in the trunk with an charging isolator and a switch. If your alternator died and you killed your main battery you could ride home on the backup battery

lostforawhile
10-01-2012, 02:13 PM
I know it's a bit late but....
wouldn't a secondary battery be a better alternative?
You could have a 2nd battery in the trunk with an charging isolator and a switch. If your alternator died and you killed your main battery you could ride home on the backup battery

well I already have a gutted alternator which is a case with the bearings and pulley,where the old one used to be, it acts as an idler for the water pump. It's not that difficult to change it to a backup, functional one, The high miler guys often run a switch to turn of their alternator, and it's been shown on the dyno to have an extremely small drag with the field shut off, not much more then an idler itself, the horsepower drag comes when it's generating current and the stator is turning against the opposing magnetic field