FJ60 Alternator Wires

[Nathan Kuwitzky]

I am replacing my stock FJ60 alternator with a “one-wire” unit from Quality Power rated at 140 amps. With the power increase I want to replace most of my main electrical wires under the hood. I have an Optima battery and am running 2 car audio amps off of it. I plan to add LED off-road lighting as well. My car audio wires coming from the battery to the amps are huge (about as thick as my pinky finger, maybe a 2 AWG). The alt to batt wire currently is probably a 10 AWG or so. I want to maximize my charging potential. I was thinking about running a 2 AWG or a 1/0 AWG. Any advice on what gauge to use (about 3 feet)?

I also want to replace my starter wire (about 5 feet). Not sure what size to use for those either.

Also my battery is currently grounded to the AC compressor mount bolt. I do not have another ground straight to the frame or the block. Any recommendations on exactly where I should ground the battery?

Input is much appreciated! Thanks!

 

[Dustin Messina]

@s0me0ldt0ys Whats the scoop on the 140 amp alternator replacement?

 

[Nathan Kuwitzky]

@s0me0ldt0ys Whats the scoop on the 140 amp alternator replacement?

The original alternator only puts out about 60 amps so a lot of people upgrade to the Mean Green but they’re pretty expensive. I found several threads about using a 140 amp GM alternator. I found a company called Quality Power online who sells GM high output alternators modded for “one-wire” install. The kit comes with a variety of mounting adapters too. The “one-wire” install is simple as that. Just mount the alternator and hook one wire up to the + battery terminal. Since you’ll have over double the amps it’s recommended that you replace your alt-batt wire and battery-gnd wires with a heavier gauge to adequately carry the load.

Here’s the link where I bought my alternator... it looks amazing! Can’t wait to put it in!

Toyota Landcruiser HIgh Output Alternators

Toyota Landcruiser High Output Alternators Below are the available amperages we have for the Toyota Land Cruiser 1969 to 2016. Our high output alternators are a direct bolt-in replacement for your original factory alternator. Please note that we may need up to five working days to build...

www.qualitypowerauto.com

 

[Dustin Messina]

The original alternator only puts out about 60 amps so a lot of people upgrade to the Mean Green but they’re pretty expensive. I found several threads about using a 140 amp GM alternator. I found a company called Quality Power online who sells GM high output alternators modded for “one-wire” install. The kit comes with a variety of mounting adapters too. The “one-wire” install is simple as that. Just mount the alternator and hook one wire up to the + battery terminal. Since you’ll have over double the amps it’s recommended that you replace your alt-batt wire and battery-gnd wires with a heavier gauge to adequately carry the load.

Here’s the link where I bought my alternator... it looks amazing! Can’t wait to put it in!

Toyota Landcruiser HIgh Output Alternators

Toyota Landcruiser High Output Alternators Below are the available amperages we have for the Toyota Land Cruiser 1969 to 2016. Our high output alternators are a direct bolt-in replacement for your original factory alternator. Please note that we may need up to five working days to build...

www.qualitypowerauto.com

Awesome. Looking forward to seeing some install pics.

 

[Seth S]

Battery to starter cable is 2 gage I believe. I highly recommend going to your local "Airgas welding supply" store as they sell coils of different gage welding cable and its very reasonable on price and makes for great battery cables. You could buy a 25' roll of 2 gage cable and have enough to do almost anything on your truck and be a significant overkill for current carrying capability.

Engine grounds:

I would locate any unused and tapped boss on the Passenger side of the engine and use it for a ground wire. Run a tap through to clean up the threads and then also clean up the block surface where the eyelet connector will seat. You might mount a busbar on the fender and run a wire from the ground terminal to it and then connect all your new grounds from there. I'd recommend grounding to the chassis as well and to the fender where the stock wire would have connected.

last night I bought 25' of 4 gage welding cable for about $31 iirc. I bought some connectors, heat shrink, marine battery terminals, and a simple crimper tool. Made a new cable for the back of the alternator for a cost of about $6. I have plenty left over to run all new grounds in 4 gage.

When sourcing a new high output alternator you might want to see if the supplier can provide you with a current vs rpm plot. You don't want to end up with a unit that doesn't make good power until 2500 rpm etc. I'm guessing that the unit you have gotten will not produce 140 amps at idle and if it does so you might find that the stock belt is unable to provide enough friction to turn it.

for reference....the stock alternator rated to 60 amps equates to 756 watts of power @ 12.6V or 840 watts @ 14V. In a stock truck you need about 120 Watts for the headlights, Not sure what the demand is for the stock ignition but conservatively guess 100 watts (6 to 8 amps). all the other random small lights on the car maybe 100watts. left over so far about 400 watts for the blower motor, horn, radio, wipers etc. but at idle you might have only 30 amps on hand because of the how the alternator is built.....so in the stock case you are fine. In your case going to LED lights would actually draw less current than stock so thats a booster but clearly your power hungry amps are the bigger issue. If you are not running multiple batteries you will probably want to consider it as the truck and all electrical accessories run off the battery....the alternator is just there to keep the battery charged.

 

[Seth S]

Did you see this chart on the site you bought the alternator from? Should help answer a lot of your size/length questions

 

[Nathan Kuwitzky]

Th

Battery to starter cable is 2 gage I believe. I highly recommend going to your local "Airgas welding supply" store as they sell coils of different gage welding cable and its very reasonable on price and makes for great battery cables. You could buy a 25' roll of 2 gage cable and have enough to do almost anything on your truck and be a significant overkill for current carrying capability.

Engine grounds:

I would locate any unused and tapped boss on the Passenger side of the engine and use it for a ground wire. Run a tap through to clean up the threads and then also clean up the block surface where the eyelet connector will seat. You might mount a busbar on the fender and run a wire from the ground terminal to it and then connect all your new grounds from there. I'd recommend grounding to the chassis as well and to the fender where the stock wire would have connected.

last night I bought 25' of 4 gage welding cable for about $31 iirc. I bought some connectors, heat shrink, marine battery terminals, and a simple crimper tool. Made a new cable for the back of the alternator for a cost of about $6. I have plenty left over to run all new grounds in 4 gage.

When sourcing a new high output alternator you might want to see if the supplier can provide you with a current vs rpm plot. You don't want to end up with a unit that doesn't make good power until 2500 rpm etc. I'm guessing that the unit you have gotten will not produce 140 amps at idle and if it does so you might find that the stock belt is unable to provide enough friction to turn it.

for reference....the stock alternator rated to 60 amps equates to 756 watts of power @ 12.6V or 840 watts @ 14V. In a stock truck you need about 120 Watts for the headlights, Not sure what the demand is for the stock ignition but conservatively guess 100 watts (6 to 8 amps). all the other random small lights on the car maybe 100watts. left over so far about 400 watts for the blower motor, horn, radio, wipers etc. but at idle you might have only 30 amps on hand because of the how the alternator is built.....so in the stock case you are fine. In your case going to LED lights would actually draw less current than stock so thats a booster but clearly your power hungry amps are the bigger issue. If you are not running multiple batteries you will probably want to consider it as the truck and all electrical accessories run off the battery....the alternator is just there to keep the battery charged.

Thanks for all the info!! Yes, that was my plan, to run the new alternator first and eventually add a second battery. When I converted to LED headlights I immediately noticed they were dimming to the beat of the music when I had my stereo on. The regular bulbs didn’t do that weirdly enough. Someone suggested that it is because LEDs like very consistent voltage. With car stereo systems the rule of thumb is to replace the alternator with higher power, replace the wires with heavier gauge, replace the battery with a stronger one and last resort is to add a capacitor. I already have a strong Optima batt so I figure I’ll do a more powerful alt and wires next. Hopefully I don’t run into belt issues like you said. I’ve seen a lot of threads of people running these GM alts in their 60 series Cruisers with great results so I’m guessing it won’t be a problem.

 

[joebattle1]

I bought this kit from a Mud member.

FJ60/FJ62 Heavy Duty Battery Cable Sets

The kit costs $155.00 shipped (within US). International shipping is available. The kit includes 5 cables and battery terminal connectors. This kit fits FJ60's and FJ62's. See below for additional kits (FJ40, FJ80 and FZJ80) Kit includes: Battery positive to starter cable (with protective...

forum.ih8mud.com

 

[NookShneer]

Make your own cables. It’s silly easy.

Amazon had everything I used. 4g welding cable from the alt to the pos. post. Starter and grounding can be upgraded to 1/0 g.

Hydraulic crimper was fun to use.

 

[Nathan Kuwitzky]

Make your own cables. It’s silly easy.

Amazon had everything I used. 4g welding cable from the alt to the pos. post. Starter and grounding can be upgraded to 1/0 g.

Hydraulic crimper was fun to use.

View attachment 1996014

View attachment 1996013

View attachment 1996012

Dang! Those wires look nice! I like the braiding that you added. Might be the way to go!

 

[Seth S]

Hydraulic crimped is the way to go for sure. I had limited resources the other night and still made a cable using a match to seal the heat shrink and a $20 hammer crimper. Not the prettiest cables I’ve made but functional.

 

[s0me0ldt0ys]

There is some great info in this thread. I am starting to have a charge lamp/charge issue at idle with my 60. I am still sorting this issue out, and it may lead to an alternator or at a minimum, regulator replacement. I'll be following this to see your progress, this could be something I am interested in doing.

 

[Seth S]

There is some great info in this thread. I am starting to have a charge lamp/charge issue at idle with my 60. I am still sorting this issue out, and it may lead to an alternator or at a minimum, regulator replacement. I'll be following this to see your progress, this could be something I am interested in doing.

If the charge light comes on the. Put a volt meter across the battery and you should see the alt isn’t charging. Also measure voltage from the alternator post to the ground on the battery. If you see 14ish volts then you have a connector issue. Make sure the nut on the back of the alternator lead is tight and the battery terminals are secure and clean. Check that the battery ground cable and battery cables are in good shape.

All that is good you might just need a new voltage regulator. Easy to change and low cost.

 

[s0me0ldt0ys]

If the charge light comes on the. Put a volt meter across the battery and you should see the alt isn’t charging. Also measure voltage from the alternator post to the ground on the battery. If you see 14ish volts then you have a connector issue. Make sure the nut on the back of the alternator lead is tight and the battery terminals are secure and clean. Check that the battery ground cable and battery cables are in good shape.

All that is good you might just need a new voltage regulator. Easy to change and low cost.

Funny you mention this. I checked all of these things last night with my meter. Paying close attention to voltage drop. At idle (controlled by my newly fitted Holley Sniper) I have it idled a bit higher than stock at 810rpm. Even at the lifted idle, the battery; and alternator are showing 12.6/12.7. I tested for voltage drops on all the grounds, and also opened a couple. They appear to be free of corrosion and reflect no voltage drop when tested from alternator to those points. If I race the engine up to 1k or a little better, the battery and alternator will show 13.4. I am unhappy with this, since at even the elevated idle I get a brief flicker of charge lamp and the charge lamp buzzer. With max load applied, AC/lights/radio the voltage will fall to 12.0/11.9. I feel like its time to replace a part or two.

 

[Seth S]

At idle with the stock alternator in my fj60 and with the headlights on I am seeing 14.0v at the battery. My truck currently idles a little high around 1000 rpm. If you are seeing 13.4v at 1000rpm that sounds ok. You can put the blower motor on and the headlights and the radio and see what your voltage is on the battery.

But if you have flickering bar light it’s either a loose wire, or maybe the brushes in the alternator getting to the end of their life span.

 

[s0me0ldt0ys]

At idle with the stock alternator in my fj60 and with the headlights on I am seeing 14.0v at the battery. My truck currently idles a little high around 1000 rpm. If you are seeing 13.4v at 1000rpm that sounds ok. You can put the blower motor on and the headlights and the radio and see what your voltage is on the battery.

But if you have flickering bar light it’s either a loose wire, or maybe the brushes in the alternator getting to the end of their life span.

So, I've been considering a few options. One being to start with replacement of regulator, simply because it is a separate part I may likely need anyways. My other option I've considered is pulling it off, and taking it to the local alternator shop and having him test, clean and rework if needed. I'm seeing in this thread some aftermarket options, and I have checked OE with no real luck so far on replacements. I had thought they still at least offered the regulator as a reman part. I'm not a huge fan of throwing a parts store unit on this thing.

 

[NookShneer]

Dang! Those wires look nice! I like the braiding that you added. Might be the way to go!

PM me if you want the parts list.

 

[Nathan Kuwitzky]

I forgot I had started this thread. My original alternator finally bit the dust a couple of weeks ago so I guess it’s finally time to get off my butt and install my upgraded unit. It was easy enough to install, came with the mounting adapters and “one-wire” install. I capped off the old plug since it’s no longer used. I upgraded all of my wires from the alt to the batt, batt gnd, batt to starter, starter gnd, a couple other gnds I found and went with a SMD distribution block for all of my accessories. I went with 2 gauge welding wire that I sourced from a guy on eBay who builds them in any length you want with different size terminals to suit your needs. I now have strong starts, bright lights, no more pulsing headlights when I run my tunes. I’m reading 13.5 volts at idle. Definitely worth the money!

 

[Seth S]

Nice job. I’ve since learned about marine cable which holds up to the elements better than welding cable. Welding cable should still last for a long time though.

 

[Meshal]

Thank you for all info provided!
What is your take on the Quality Power alternator?

I forgot I had started this thread. My original alternator finally bit the dust a couple of weeks ago so I guess it’s finally time to get off my butt and install my upgraded unit. It was easy enough to install, came with the mounting adapters and “one-wire” install. I capped off the old plug since it’s no longer used. I upgraded all of my wires from the alt to the batt, batt gnd, batt to starter, starter gnd, a couple other gnds I found and went with a SMD distribution block for all of my accessories. I went with 2 gauge welding wire that I sourced from a guy on eBay who builds them in any length you want with different size terminals to suit your needs. I now have strong starts, bright lights, no more pulsing headlights when I run my tunes. I’m reading 13.5 volts at idle. Definitely worth the money!

View attachment 2317753

View attachment 2317754

View attachment 2317755