Friend has started this install, using a 100 amp alt at idle
..
Install is on a 60 series with 12ht..
..Install is on a 60 series with 12ht..
Seond Allternator and extra battery?
- Thread starter Diesel Cruiserman
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
Going to run a separate electrical system. Front winch, probably rear winch, fridge freezer, webasto and lights. There's more accessories but you get the idea.
The 12ht factory alternator is no powerhouse @ about 55 amps on a good day. I don't have AC, and with the bracket in place it was logical to do. I've managed to do it with factory belt as well.
I learned the hard way that Toyota factory belts make a difference, they are in fact wider than the LT or light truck belts that Gates manufactures.
The 12ht factory alternator is no powerhouse @ about 55 amps on a good day. I don't have AC, and with the bracket in place it was logical to do. I've managed to do it with factory belt as well.
I learned the hard way that Toyota factory belts make a difference, they are in fact wider than the LT or light truck belts that Gates manufactures.
I have been slowly working on several things at once. I've realized that I've been driving around with a half way defective alternator for 2 years. Never could figure out why it never was up to snuff. It was a 24 V conversion and the rotor(field coil) had been changed but not the stator. Now, it's been fixed up (read:$250 later) the factory vacuum alt is pushing high amps and working great! I've gone with an Odyssey 31 series battery for starting now. There are further wiring issues with the truck, ie grounds not complete.
Both batteries are grounded to the body, and the engine. Neither has been grounded to the frame. I suspect this could be an issue. Any opinions on this?
I'm looking for a mechanical, simple solution to having separate electrical system with second battery, that if required ( factory alternator failure ) I can switch over to run both batteries on the second alt.
anyhow, that's where it's at now.
Both batteries are grounded to the body, and the engine. Neither has been grounded to the frame. I suspect this could be an issue. Any opinions on this?
I'm looking for a mechanical, simple solution to having separate electrical system with second battery, that if required ( factory alternator failure ) I can switch over to run both batteries on the second alt.
anyhow, that's where it's at now.
That's how my 60 is setup. I'll find a link to the thread.
Here it is...
https://forum.ih8mud.com/60-series-wagons/498610-dual-alternator-desmogged-2f.html
In normal driving the stock battery/alternator powers all the stock loads, except for the headlights. All lights and accessory loads are on the second battery/alternator. Splitting off the headlights to the second alternator means everything electrical works better (aka, have enough amps).
Because of the various battery switches, I can run everything on either #1 or #2. When camping, I disconnect the stock battery and run off of the aux only. I did have the VR on the primary fail on a long road trip, but a quick flip of a switch and we were running on the aux system. It was a PIA to wire up, but works great.
The trickiest part was the sensing wire on the aux alt. I ended up using a relay, with the input from the coil. Truck is on, relay energizes, alt sensing wire sees voltage, alternator fires up. If you use a self-energizing alternator, no need for this.
Last edited:
Thanks for the link. Very well thought out process. I was working on a separate system from the truck. Run all the primary stuff from the start battery, then lights, winches, fridge from the secondary system/second alternator completely separate from the primary system. I will look closely at what you've done and see try to understand it all.
Is your second battery a deep cycle? What are the numbers on it, if I may ask. I've got a 12ht, so starting amps is an issue.
J
Is your second battery a deep cycle? What are the numbers on it, if I may ask. I've got a 12ht, so starting amps is an issue.
J
Soon i'll post some photos of my 12ht(with A/C) dual alternator set-up
I"m interested to see that.
Both batteries are Interstate deep cycle marine batteries. I think it's a group 27. Here's a link to the numbers
http://www.interstatebatteries.com/cs_estore/content/product_info/marine_f.asp
This battery has been amazing as a starting battery. I had a carb issue last winter...it took 30+ minutes to start after skiing (15 degrees). Crank for 15 secs, rest for 30. It cranked a little slower at 30 minutes, but not too much. I have since replaced the carb, but the battery was 3 years old at that point, and is still going strong.
I am doing a quick update on this. I am back at work sitting in a hotel in Edmonton pondering all things landcruiser. I wrote an email to Daniel Stern about getting some driving & fog & headlight upgrade ideas. He asked which alternator I had. So I looked it up on the internet, just curious to see the specs myself, from the part number.
It's a Prestolite 8MR2401UA.
So here are my questions that have arisen.
It has no capacitor. I thought that a capacitor was for reducing radio frequency interference? Without one, will this alternator make that buzzing sound over the radio in sync with engine rev's?
It has no diode trio assembly? Lots of alternators do. Why does this one not?
This is the output schematic for the alternator. It has a kick in @ 1700 RPM shaft speed. I haven't looked yet, but with a 3 1/2" pulley for the belt, what is the equation for calculating that proportion. I initially misunderstood, and was concerned that I'd have to rev the crap out of it to get this thing to work, but I was going the wrong way.
So with a 3 1/2" pulley, engine at 700 RPM idle, what speed is the 7/8" shaft turning?
I've got a 12HT, 12V. I have dual batteries. I will be running smaller case size batteries on the one side in parallel to run the starting/truck assy. The other side will be a series 31 AGM deep cycle. This will feed a buss with fuses and circuit breakers, as well as be the power source for the Warn 9500 HP compressor winch up front, and the Warn M6000 in the rear.
Re: winches. I've been advised, which I will follow through on, to not maintain constant power to the winches. There is as expected a continual parasitic drain, but also something which I'd not thought about. Especially with the rear winch, the cables are long 2-0 gauge, and they will slowly break down over time with a continual power supply running through them. With no power, the cables are essentially inert, no power, no corrosion. Really makes sense.
Not to mention the safety of high amp runaway if things go bad, so both winches will be on isolator switches from the battery.
That's it for now. If anyone can either answer my questions, I'd be very grateful.
J
PM me if in Edmonton, always up for happy hour 
It's a Prestolite 8MR2401UA.
So here are my questions that have arisen.
It has no capacitor. I thought that a capacitor was for reducing radio frequency interference? Without one, will this alternator make that buzzing sound over the radio in sync with engine rev's?
It has no diode trio assembly? Lots of alternators do. Why does this one not?
This is the output schematic for the alternator. It has a kick in @ 1700 RPM shaft speed. I haven't looked yet, but with a 3 1/2" pulley for the belt, what is the equation for calculating that proportion. I initially misunderstood, and was concerned that I'd have to rev the crap out of it to get this thing to work, but I was going the wrong way.
So with a 3 1/2" pulley, engine at 700 RPM idle, what speed is the 7/8" shaft turning?
I've got a 12HT, 12V. I have dual batteries. I will be running smaller case size batteries on the one side in parallel to run the starting/truck assy. The other side will be a series 31 AGM deep cycle. This will feed a buss with fuses and circuit breakers, as well as be the power source for the Warn 9500 HP compressor winch up front, and the Warn M6000 in the rear.
Re: winches. I've been advised, which I will follow through on, to not maintain constant power to the winches. There is as expected a continual parasitic drain, but also something which I'd not thought about. Especially with the rear winch, the cables are long 2-0 gauge, and they will slowly break down over time with a continual power supply running through them. With no power, the cables are essentially inert, no power, no corrosion. Really makes sense.
Not to mention the safety of high amp runaway if things go bad, so both winches will be on isolator switches from the battery.
That's it for now. If anyone can either answer my questions, I'd be very grateful.
J
PM me if in Edmonton, always up for happy hour