I'm excited to install mine tomorrow! I'll post up and let everyone know how it goes. Already took the alternator to a shop to have it bench tested, and the guy said it was outputting over 150 "without him even really pushing it." Good sign #1.
Upgrading stock alternator to 130/150 amp
- Thread starter Photoman
- Start date
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NLXTACY
Wits' End
Damn, I was hoping to get to this before my trip but its not looking good. I have everything in my garage now just no time to install. 
- Thread starter
- #83
I'm glad you are still making lots of amps and thanks for the update.
Here is a chart that I found interesting. It shows typical amp draw of various automotive devices. It was published by 4-Wheel & Off-Road magazine December 1997. I’m sorry I lost the link so can not credit the article it came from.
Electrical Circuit Amperage
Air Conditioner 12-20
Backup lights (two) 3-4
Brake lights (two) 3-4
Cigarette lighter 10-12
Clock 0.5
Dome lamp 1
Headlamp dimmer 2
Headlights (two, low beam) 8-9
Headlights (two, high beam) 13-15
Heater/Defroster 6-10
Horns (two) 20
Ignition 2-4
Instrument panel and gauges 4
License plate light 1
Parking lights (two) 2
Power door locks 5
Power seat 25-50
Power windows 25-50
Side-marker lights 2
Starter solenoid* 10-15
Taillights 5
Add to the list:
wipers 3-6 amps
radio or sound system 2 to ∞ amps
electric fuel pump 7-15 amps
injectors 2 amps
Winch ≈ 400 amps
Toyota overhead – ignition, ecu, abs, diff lock, etc. ?????
Gps, laptop, mirrors ????
aux. lights – add watts of all bulbs together – roughly divide by volts = amp draw
Example - 2 Hella 4000’s with 100 watt bulbs. 100+100=200 200/12 volts=16.66 amps
aux. fans – see fan specs and use above formula to work out amp draw.
Example - I replaced the stock engine fan with 2 electric Spal pancake racing fans. They required 25 amps to run. I had them come on with engine start so this was a constant 25 amp draw.
Just like in a house service we don’t run all things at once but it was interesting to see how fast things can add up.
Bill
Bill,
I've had the new alternator installed for a couple of weeks now and it works great. Thanks for putting this bracket together!
I do have a question though: I haven't upgraded the white wire yet, and wanted to verify that it's only required when I draw additional (more than stock) loads? I plan on rewiring it soon, before I add any additional loads (e.g. inverter), but wanted to make sure it was safe in the meantime.
I've had the new alternator installed for a couple of weeks now and it works great. Thanks for putting this bracket together!
I do have a question though: I haven't upgraded the white wire yet, and wanted to verify that it's only required when I draw additional (more than stock) loads? I plan on rewiring it soon, before I add any additional loads (e.g. inverter), but wanted to make sure it was safe in the meantime.
- Thread starter
- #87
Keep in mind the condition of your battery. Any time the voltage regulator senses the system voltage is down (like after you start the cruiser) it will try to bring the system voltage back up. In doing so it will possibly try to use the full output of the alternator. So its not just the additional load of accessories that can cause more than stock loads.
Bill
Got it, thanks. I'll be rewiring it soon then. I have a brand new huge battery, so hopefully it doesn't get taxed too bad on startup.
I did the first half of the install this weekend (got the alternator mounted and running.) Still running the stock wiring, I'll fix that this week. My install seemed really easy compared to some of the others here, I went with the 7450 belts and did not have to tap-out the upper mount bushing or anything.
I really want to think about the wiring and come up with a game plan of what I really want/need and how to integrate that with all of my other wiring (dual bats, 2 ga to rear for inverter/accessories, other craziness.)
Thanks Bill for making this bracket and making a high-output alternator install a possibility!
I really want to think about the wiring and come up with a game plan of what I really want/need and how to integrate that with all of my other wiring (dual bats, 2 ga to rear for inverter/accessories, other craziness.)
Thanks Bill for making this bracket and making a high-output alternator install a possibility!
OK, after thinking about how exactly I want to upgrade the wiring, I have a question or two:
I am looking at the EWD189U, page 48, and it looks like the easiest way to upgrade the wiring is simply to lift the ring off of the B alternator terminal and wrap it up so to isolate it from shorting on something. Then run a larger wire directly from the battery to the B alternator connector through a fuse. This was suggested earlier by Brian894X4, but I dont think anyone caught the simplicity of it. From what I can tell, this is a legit solution, but please correct me if I'm wrong.
Second, where can I source the parts circled in red:
I know I can probably get the blue sea stuff from west marine, but what about the battery terminals? I was just going to buy the whole harness from urban land cruisers, but I think I'll just build my own.
Thanks!
I am looking at the EWD189U, page 48, and it looks like the easiest way to upgrade the wiring is simply to lift the ring off of the B alternator terminal and wrap it up so to isolate it from shorting on something. Then run a larger wire directly from the battery to the B alternator connector through a fuse. This was suggested earlier by Brian894X4, but I dont think anyone caught the simplicity of it. From what I can tell, this is a legit solution, but please correct me if I'm wrong.
Second, where can I source the parts circled in red:
I know I can probably get the blue sea stuff from west marine, but what about the battery terminals? I was just going to buy the whole harness from urban land cruisers, but I think I'll just build my own.
Thanks!
- Thread starter
- #91
OK, after thinking about how exactly I want to upgrade the wiring, I have a question or two:
I am looking at the EWD189U, page 48, and it looks like the easiest way to upgrade the wiring is simply to lift the ring off of the B alternator terminal and wrap it up so to isolate it from shorting on something. Then run a larger wire directly from the battery to the B alternator connector through a fuse. This was suggested earlier by Brian894X4, but I dont think anyone caught the simplicity of it. From what I can tell, this is a legit solution, but please correct me if I'm wrong.
Second, where can I source the parts circled in red:
I know I can probably get the blue sea stuff from west marine, but what about the battery terminals? I was just going to buy the whole harness from urban land cruisers, but I think I'll just build my own.
Thanks!
There are two white wires in that “B” terminal connector on the alternator. One charging big white wire goes to the battery positive and is protected by connecting through about a #14 fusible link wire in the AM1 plastic box. The other white wire at the alternator “B” terminal is about a #10 gauge wire and sends power to the under hood fuse box. Before it gets to the under hood fuse box it splits and supplies power to some circuits in the dash fuse panel. So in this stock configuration power is coming directly from the alternator on this #10 wire to supply these circuits.
If the wire is just removed from the alternator and a new heavy wire is run between the alternator and the battery positive, the under hood fuse box and the under dash fuse panel circuits are now being fed back through the #14 fusible link wire. Like this – power from alternator up big new wire through new fuse to battery positive – from battery positive back through old 14 gauge fusible link wire through old former big charging white wire then to old 10 gauge white wire to fuse panels. It will work, but all those circuits could have less power since they are being back fed through the smaller fusible link wire. To say it another way from faulty memory, the headlights, EFI, tail light relay, defog, FL heater, ECU B, and OBD will now all be fed through the 14 gauge fusible link. Hope this makes sense. Sorry I do not have that version EWD.
Wrangler NW among others has those items circled.
Hope this helps.
Bill
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NLXTACY
Wits' End
I use Dave's Marine in Vegas.
NLXTACY
Wits' End
Wrangler is starting to cut out a large set of their inventory numbers in order to concentrate on their alternator/dual battery biz. Make sure to call because you wont be able to find it on the site any longer.
BTW Bill, I have YET to finish this
BTW Bill, I have YET to finish this
when i went to NAPA and asked for a 150 amp fuse and fuse block, the guy about crapped himself. He said that is a HUGE fuse. I had no idea how big it was until he brought it down from in the back. It is a huge fuse.
SDnative, that's exactly what i did. Upgraded that wire and just cut the other wire out completely.
I think i used a busman fuse. Here is the best pic i can take right now since it's dark outside. i'll try to do better tomorrow. Mine runs from the alternator to the fuse, fuse to battery.
SDnative, that's exactly what i did. Upgraded that wire and just cut the other wire out completely.
I think i used a busman fuse. Here is the best pic i can take right now since it's dark outside. i'll try to do better tomorrow. Mine runs from the alternator to the fuse, fuse to battery.
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Bill, thanks for the reply.
I see what you are saying, but I'm still not sure that is a problem. The fusible link, instead of protecting the large current going from the alt to the battery, now only has to handle the smaller current going from the battery to the fuse box. As far as current limiting, it may as well be a solid piece of wire, as it is now way oversized for it's new duty. As far as I can tell, the only downside to doing this would be the lack of proper fusing between the battery and the fuse box (maybe 20" of wire on mine). The extra distance of wire from the fuse box to it's source (previously the alt, now the battery) would have negligible voltage drop due to resistance. When the vehicle is running, the alt B terminal and the battery + are at the same potential anyway, minus the small drop across the link (which I assume is negligible as well).
The only thing I would probably do is use a smaller rated fuse and holder in place of the fusible link inside the little AM1 box only to protect the wire from the battery to the fuse box.
I tend to over-analyze everything, and just wanted to make as few wiring changes as possible. I have not traced out the wires in the vehicle yet, so far have just been looking at the EWD.
What do you think? I'm pretty sure it will work and there will be no measurable difference in voltage levels or current draw. Unless I am missing something.
Sorry to rehash this over again.
BTW: thanks for the Wrangle link. I'll give them a call.
- Thread starter
- #96
It is true that because of its short length the fusible link has to carry at least 80 amps as that is the output of the stock alternator, at least for a short time.
Since you are looking for making as few wiring changes possible you could maybe consider one other way. Run the new large charging wire through a new fuse to the battery positive and just leave the stock wire on the alternator "B" post. Then unbolt the fusible link in the AM1 box and wrap the battery positive end with tape. This way there is minimum wiring changes and those fuse box circuits would still be fed directly from the alternator through that larger #10 wire.
Another consideration while you are analyzing and doing what you originally proposed. In a scenario where the engine could still run and either the fusible link or the fuse you replace it with blows, then you could possibly be without headlights and EFI, and ECU B since there would now be no feed to those circuits in the fuse boxes. In other words not running and possibly blind. A short in 1 circuit could shut them all down. Probably not fun to just have a short in the headlights shut the engine down.
There is a reason Toyota fed those circuits directly from the alternator and not from the battery. I like to preserve the original intentions as much as possible.
Hope these thoughts help.
Bill
Bill,
Got the bracket for the upgrade to the 150 amp alternator, looks great by the way, thanks. I have been reading through the posts about the wiring and have a question for you electrical types. I saw that you recommend using a fuse between the alternator and battery and it should be 20% greater than the amps being pushed through the wire. I see some people using the 150 amp fuse or breaker. I am going with the 150amp alt, so do I need a 180amp fuse? I am having trouble finding one in that size seems they go from 150 then jump to 200. Will the 150 work or is it safe to jump up to the 200amp fuse?
Got the bracket for the upgrade to the 150 amp alternator, looks great by the way, thanks. I have been reading through the posts about the wiring and have a question for you electrical types. I saw that you recommend using a fuse between the alternator and battery and it should be 20% greater than the amps being pushed through the wire. I see some people using the 150 amp fuse or breaker. I am going with the 150amp alt, so do I need a 180amp fuse? I am having trouble finding one in that size seems they go from 150 then jump to 200. Will the 150 work or is it safe to jump up to the 200amp fuse?
That would work. I like that idea better
.That's exactly what I was looking for. I wanted to make sure I thought of every scenario. I guess if toyota spends big $ on development, it's probably sound. Good call.
Thanks again Bill, I'm loving the new alternator!
Dont take my recomendation, but I have heard reports of the 150a alt putting out more like 160-170. Probably should go with the 200a.
- Thread starter
- #100
Thank you.
Maybe an electrical type can correct me if I'm wrong but I will take a shot at it.
The fuse is there to protect the wire and the components. If you are using a 4 gauge wire as many are, I think the wire is rated for 125-150 amps maximum around 4-5 feet long. So based on that wire size and length a 200 amp fuse might be a bit much.
I’m pretty sure these Mega fuses have a slow blow component.
I just looked and on the back of the fuse package there is a scale that shows how much over current protection and for how long. I looked at a couple of different Mega size fuses I have and they both have this same slow blow percentage rating scale. So a 150 amp fuse with this slow blow feature should be able to handle a current surge or spike for a short time without blowing. In looking it says the fuses will take 130 percent over current for 10 minutes. So a 150 amp could take 195 amps for 10 minutes before blowing. For what its worth, 200 percent for 3 1/2 seconds.
Here is an example with a little information. Lol, I don’t know who would buy a used fuse but I guess it takes all kinds.
The company does show they make a 175 amp if you scroll down a bit but don’t know about the availability here.
sdnative - It's good to hear you got the bad boy in there.
Bill
