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Has anyone upgraded to 130 amp alternator


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I found a direct replacement alternator that puts out 130 amp, bolts right in, and uses all of the Toyota electrical hookups. It works with the stock gauges and idiot lights.

I will be making the following changes:

1. New battery isolator (relay style) rated at 200 am

2. New circuit breaker leading to the coach battery-manual reset, rated for 150 amp

3. New 4 gauge wire leading from isolator to circuit breaker and from circuit breaker to coach battery

I decided on this approach because I want more charging capacity and I did not like the idea of switching over to the GM alternator. I would have had to buy a GM unit, mounting bracket, adapter for wire harness, etc.

I was able to get the isolator and circuit breaker online pretty cheap. The alternator was a little pricy but the total cost was only about 7$75 more than a used alt and all of the brackets & adapters.

I will let you know how everything works. I also am adding a volt meter on the dash that reads the coach battery voltage so that I can keep track of everything. I have a 12 compressor refrigerator that works great but pretty much maxed out the charging capacity of the stock alt.

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I've got a Delco CS-144 alternator on my 78 Toyota that is rated 140 amps. That max 140 amp rating is kind of meaningless on a Toyota with a single V-belt drive. A single V-belt does not get enough traction to power an alternator at 140 amps. It takes two V-belts or a ribbed flat belt. I installed mine because I wanted the high charge current at engine idle speed. The newer-generation alternators like the CS-144 can charge 50-60 amps at engine idle (depending on the pulleys used). I've got the "coach" batteries in back, connected to the front alternator with 15 feet of #2 cable. I was going to install a latching-relay - but changed my mind at the last minute and put in a "smart" battery separator. Basically a voltage sensing relay that gives priority charge to the cranking battery. I got my Delco CS-144 brand new (not rebuilt) for $120. I didn't find mounting and wiring a Delco instead of a Toyota OEM Nippo or Hitachi to be any problem at all. Nice thing about the CS-144 is the footprint is smaller then the older "high output" alternators like the Delco SI series.

I don't understand how a 12 volt compressor refrigerator maxed out your original charging system. Most draw around 6 amps when running and at 70 degrees F they only run 1/4 of the time. 15 minutes an hour, 6 hours a day. Averages to about 2 amps per hour and half that if you add some insulation. A standard 45 amp or 60 amp Toyota alternator easily puts out 30 amps at engine idle. Should not be an issue with a compressor refrigerator. Not unless you're driving at night and have a bunch of other accessories on at the same time. A carbed truck with a non-electronic trans only needs around 5 amps to run and maybe 15 amps more if all the lights are on including the high-beams. That leaves plenty to run the refrigerator so the charge light should not glow when you're stopped at a red light and the engine is idling. Even if it did, all would be fine as soon as you started moving again.

I used to have a class A Winnebago with a 45 amp alternator. With that, at night - and the absorption refrigerator on in DC mode - my charge light would come on at every red light. But that thing drew 12 amps all the time and the pulley ratio had the alternator spinning slower then most.

My 86 Blazer Chalet had a 60 amp alternator for years. I used a large AC refrigerator (4 cubic foot) with an inverter and never had any charge problems.

I don't know what you chose for a battery combiner-separator relay. For years I've been using full-time rated, low-draw, 200 amp relays. Very simple and reliable. But the constant 1/2 amp draw they use always bugged me. So with my newest rig, I was going to use a latching relay that uses NO power to stay engaged or disengaged. But in a weak moment, I got the "smart" relay instead. More complex then I originally wanted but sometimes I fall victim to wanting new-tech gadgets.

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I was going by what several people on this forum had said about the stock alt. I know that my refrigerator draws 5 amps and I added 2 inches of styrofoam insulation to top and sides when I installed it.

I have not ordered the alternator yet so maybe I will just see how the heavier wire to the coach battery and the new isolator work out. I had issues with the solid state isolator not always giving the coach battery any juice. I would plug a voltmeter into the rear power tape and it did not increase voltage when I started the motor. I will try the heavy wire and start measuring voltage at every point of connection from front to back.

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I was going by what several people on this forum had said about the stock alt. I know that my refrigerator draws 5 amps and I added 2 inches of Styrofoam insulation to top and sides when I installed it.

I have not ordered the alternator yet so maybe I will just see how the heavier wire to the coach battery and the new isolator work out. I had issues with the solid state isolator not always giving the coach battery any juice. I would plug a voltmeter into the rear power tape and it did not increase voltage when I started the motor. I will try the heavy wire and start measuring voltage at every point of connection from front to back.

The "solid-state" rectifier-based isolators all have some loss but it sounds like yours wasn't working at all. Basically they just take the charge current from the alternator and split it in half - sending one part to the cranking battery and the other part to the "house" battery. When working correctly both batteries get charged but neither can draw power from the other. If the cranking battery was charging but the house battery was not - it sounds like the isolator is blown, or a fuse or bad connection is breaking contact somewhere.

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If you boon-dock a lot and need to make sure your house battery (s) are fully charged. Use a mechanical relay isolator and hook the house battery to the alternator side and the truck battery to the isolated side. This will ensure that the house battery gets every last erg of energy it can.

If you do a lot of short drives and stop and go, this might not be the way to go as the voltage drop across the isolator will effect the truck battery.

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Once a diode receives .7 forward bias volts it is essentially on and conducts. Electricity will seek the path of least resistance so if you have poor connections etc. the truck will charge and the house battery may not depending on the amount of time you are running the truck if at all. If the isolator diode for the coach is open it will not charge 100% of the time they either work or they don't. Once the truck is running you can check the voltage at the isolator posts 1 and 2 (it does not matter what battery is connected to 1 or 2) so if it is the same (or close) as the other one and not at your coach battery you have connection issues to the rear battery if one is decidedly higher the isolator is toes up. Battery voltage should be present at the # 1 and 2 terminals all the time (engine on or off) that is another way to tell if you have connection problems. Personally I'm not a fan of solid state isolators I am a staunch supporter of the K.I.S.S theory both work fine but the relay is far simpler and has some advantages.

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My Odyssey has a state isolator, my Sunrader had a mechanical one. Haven't really had any issues with these isolators in particular, but, my experience with solid state relays in general is that they are pretty much bulletproof. Mechanical relays are more prone to failure. So, although I do share your opinion on the K.I.S.S. rule in general, this might be a case where something more complex is better. Not that a solid state relay is exactly complicated.

There may be one other advantage to the SS isolator, in that I believe it has some sort of current limiting abilities. This feature if it does in fact exist, could come in handy if you have a habit of running the coach battery very low. Our toyota alternators aren't particularly high output and asking one to bring a near dead coach battery back up to full charge is asking a lot, especially if it's doing lots of other things like running headlights and blower motors.

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Care to share what the alternator part number that mates up like for like is Arkansas?

I like the bracket ; its the pesky wiring that scares me....

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@Totem - taken from that page:

"Works with many GM style alternators, but listed below are part numbers for the most common GM style alternators.
* AIM/NAE (Napa) 67294
* BBB Industries 72941W
* Beck Arnley 1867294
* Lester 7294SE
* Perfection 020854SE100
* Worldwide 53166

The listed part number for the NAE 67294 is 7294SE and is the most common part number used. Most auto parts stores should also be able to cross reference this number."

OR you can buy the FULL kit: http://www.lceperformance.com/High-Output-Alternator-Kit-120-Amp-22R-RE-RET-p/1080050.htm

However, I believe it would be much cheaper to source the parts individually. And as for the wiring, there's just one wire run from the Alt to the isolator. Easy as pie.

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@Totem - taken from that page:

"Works with many GM style alternators, but listed below are part numbers for the most common GM style alternators.

* AIM/NAE (Napa) 67294

* BBB Industries 72941W

* Beck Arnley 1867294

* Lester 7294SE

* Perfection 020854SE100

* Worldwide 53166

The listed part number for the NAE 67294 is 7294SE and is the most common part number used. Most auto parts stores should also be able to cross reference this number."

OR you can buy the FULL kit: http://www.lceperformance.com/High-Output-Alternator-Kit-120-Amp-22R-RE-RET-p/1080050.htm

However, I believe it would be much cheaper to source the parts individually. And as for the wiring, there's just one wire run from the Alt to the isolator. Easy as pie.

That NAPA "67294" is an old-tech Delco 12SI alternator from the late 70s to early 80s. Nothing wrong with "old" but not something I'd want to spend much money on. Certainly not a what I'd call an "upgrade." The 12SI is a common cheap swap for 60s-70s farm tractors when bought for $25 at a junkyard. The OEM type alternators (Denso) that came on Toyotas are built much better, and so are the newer (90s) Delcos e.g. the CS series (CS130 or CS144).

No matter what alternator is used - the limiting factor for max amps is the single V-belt drive on the older Toyota engines. It's lacks traction to make more then 80-90 amps before the belt slips and burns. But if you want a big alternator for the purpose of getting 50 amps at engine idle speed and NOT for the 120-140 max ratings at high revs - a big alternator is nice feature. A smaller pulley though on the stock alternator can do pretty much the same.

The stock Toyota Denso - early 45 amps or later 60 amps will make around 25-30 amps at engine idle. A Delco 12SI (older tech like the #s you gave) will make around 30 amps at engine idle. Very little difference. A later tech Delco CS series will make 50 amps at engine idle speed.

There are many different types of alternators that swap in pretty easy. The older Delco 10SI and 12SI alternators are bulky, cheaply built - but also the most common when looking for so-called "upgrades" on the Net. That because they are so common and simple.

Alternator math kind of works like this.

Just about any alternator must spin at a minimum of 1600 RPM to do anything. Max output is often limited by highest RPMs and abiliity NOT to burn out. Many alternators can make twice what they are rated at.

A car or tractor maker decides on the how fast the alternator spins at engine idle by their choice of pulleys.

Many American cars with Delcos use a pulley ratio of 4.5 to 1. That means that the alternator always spins four and a half times faster then the engine. It is a cheap way of getting more power from an alternator but it also cuts down on its service life. If the engine idle speed is 800 RPM, the alternator is spinning at 3600 RPM.

Many alternators on HD applications intended to last longer - spin slower. 70s-80s Toyota pickups with four banger engines have a pulley ratio of only 2 to 1 ( a HD set-up). A 6" crank pulley and a 2 7/8" alternator pulley. That extends the life of the Denso alternator but also lowers its output. When the engine is idling at 800 RPM, the alternator is only spinning at 1650 RPM (just enough to work).

So - you could just stick a typical Delco 2 1/4" pulley on the stock Toyota Denso alternator and get a big increase in low end charge power. That would make it a 2.6 to 1 ratio and at engine idle - the alternator would spin at 2000 RPM and produce 40 amps.

So - a smaller alternator pulley is a cheap $10 upgrade to make more power at low speeds. Note though that the smaller pulley also has less belt traction area and can put more wear on the v-belt.

If there was a way to put twin v-belt drive, or serpentine drive on an older Toyota, it would be easy to bolt up a 120 to 200 amp alternator. Even my cheap 2002 Dodge minivan has a Denso 160 amp alternator that's not much bigger then the 45 amp alternator in older Toyota trucks. The belt -drive is the problem though. A 160 amp alternator can work as a 2200 watt power source if all is rigged up correctly.

Some specs:

Denso 45 or 60 amp (OEM on 70s-80s Toyotas - makes 25-30 amps @ 1600 RPM

Delco 10SI, 63 or 72 amps - makes 23 amps @ 1600 RPM

Delco 12SI, 66, 78, 94 amps - makes 30 amps @ 1600 RPM

Denso HS120 (Dodge minivan) - makes 53 amps @ 1600 RPM, 88 amps @ 2000 RPM, 111 amps @ 2400 RPM, 169 amps @ 5000 RPM and 178 amps @ 6000 RPM.

Obviously, you can see where a brand new (not rebuilt) HS120 Denso for a Dodge minivan for $85 is a good candidate IF you had belt enough to power it. But even with a single v-belt, it would work fine up to 80-90 amps.

MUCH better alternator then the cheaply built Delco 10 and 12SIs being sold all over the Net.

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I agree with JD and by the way JD that was an awesome explanation and I was thinking the same thing but didnt have the brass to post it as he really seems to want to put the old alternator on.

I will say that there is an alternator that requires no special bracket and wont wear any worse on the vBelt though nor will it need a bracket. Too bad it costs over $500

http://www.fasttrackautoparts.com/item/136138-powermaster-41280-alternator

*note requires your stock pulley.

you will get a whopping 110 at idle on this puppy. This would be a REAL upgrade. :)

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Some photos of alternators showing size difference. The Nippo-Denso 120 amp isn't much bigger then the Toyota Nippo-Denso 45 amp. Note that smaller pulley on the OEM Toyota 60 amp as compared to the 45 amp. I suspect it's just the pulley that increases the output and I suppose the 60 amp unit has better rectifiers and cooling to endure making higher amps.

post-6578-0-48219600-1370968527_thumb.jp

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I guess I just do not understand why anyone wants the big alternator. If one could be plugged in with no other mods, maybe so. Changing the belt drive system is going to get rather involved (IMO).

The only reason I can imagine is if one wants to charge a battery bank while underway. I would just get a honda 2000 (or even a 1000) to do it - probably more fuel efficient and a lot simpler.

Even if one gets all that extra power routing it to a battery bank will be interesting.

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I cannot speak for others - but I have explained many times why I prefer a bigger alternator. If I install a so-called "120 amp" alternator - the purpose is to get 50-60 amps at engine idle speed. NOT to get 120 amps at higher speeds. The stock 45 or 60 amp alternator can only make 25-30 amps at engine idle. Having 50-60 amps at engine idle enables me to use heavy appliances e.g. a microwave inside my RV with no stand-alone fuel-driven generator needed and no grid power from an outside source. That being said - I've seen a few RVs that use big main-engine driven alternators as 2200 watt AC generators via an inverter or an AC tap that some alternators have. Some of the big Leece-Neville (Prestolite) alternators used on emergency vehicles make AC directly.

Having a big alternator for low speed and high amps is the same reasoning why many newer vehicles have huge alternators when they leave he factory. My 2002 Dodge Caravan with a 3.3 liter V6 has an OEM 160 amp Nippo-Denso alternator. The main purpose is NOT to make 160 amps available. It is used so 50-60 amps are available at low engine speeds so many high-draw items can be used. In the "old days" having a small "dynamo" wasn't a big issue although cars with brushed-generators often has the charge light come on at engine idle with nothing being used. Today - cars/trucks with big sound systems, GPS, DVDs, TVs, on-board computers, electronic fuel injection, electronic-shifted transmissions, electric power steering, electric grid heaters, etc. - the higher amps at low speeds is a requirement.

I don't agree with a separate fuel-driven generator to be a "simpler" setup then making electric power with the main engine. Keeping two engines running is more complicated then just one. Generators can be especially problematic if they spend most of their time not being used and aren't "exercised."

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JD, Exactly:

High amps at low speed (idle) would be the main reason I would do it. I use my truck engine as my "jenny". My battery needs a charge after running the microwave and elec coffee pot for 30 minutes. So I hit the remote start on the truck and let it idle for 15 minutes. This charges the battery, but would be better if I had a higher amp alt.

One other thought, I may change the pully on my existing alternator and make it a little smaller.

None of this has been a problem yet,

John Mc

88 Dolphin 4 Auto

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One other thought, I may change the pully on my existing alternator and make it a little smaller.

None of this has been a problem yet,

John Mc

88 Dolphin 4 Auto

The problem with smaller pulleys is - they give less belt traction surface area. That can be a problem on a single V-belt system. But the OEM 60 amp alternators that came on Toyota seemed to work OK. The stock 45-50 amp alternator on the Toyota trucks have pulleys with a 2 13/16" OD. The newer 60 amp OEM alternator have pulleys with a 2 9/16" OD.

Just for reference -my 88 Chevy diesel Suburban came new with a 74 amp Delco and a 2 1/4" pulley. It had a lot of belt slippage problems at engine idle speeds.

Keep in mind that this diesel not only have battery draw from cranking but also 80 amps for 10-20 seconds to fire the glow plugs. Once started the battery demanded full amps from the alternator the belt slipped. The "fix" was to install a 2 5/8" pulley. More belt traction.

Funny that all my 80s Subarus with 1.8 engines and 50 amp Hitachi alternators have dual-belt pulleys.

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I got my problems sorted out and decided that I did not need a larger alt.

It turned out that I had a couple of problems that I did not know about.

1-one year old solid state isolator does not work at all.

2-8 gauge wire from isolator to coach battery.

3-8 gauge wire from isolator to truck battery.

4-6 gauge wire from alt to isolator

5-bad connection at alt.

6-bad ground in the coach.

After a pile of sorting things out, I am now getting a good charge at both batteries and have not had a problem with charging anything.

The solutions- I replaced all of the wire with 4 gauge wire w/crimped and soldered lugs, new relay type isolator, checked voltage lose at front and rear batteries and it is much less loss than before the heavier wires.

Before all of the changes, I had 14.5 volts at the alt, 13.? at isolator and only 12.7 volts at the truck battery and 12.5 volts at the rear battery. Thanks for all the help with eventually getting things working right.

You could go broke if you had to pay someone to do all of the work on these 25 plus year old vehicles.

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There is another issue that enters into the mix is wire size just changing the alternator isn't going to do it alone you can only push so much current down a #8 wire before it starts to get hot. Our cop cars when I retired had 260 amp alternators they were fed with a #1 copper wire and driven with a 1 1/2 flat belt. I guess the question is how many times did you find your battery dead because it did not receive a good enough charge from the 65 amp alternator?

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I remember when I got my Escaper, only 12.3v at the coach battery. Started repairing things and found 4 different sizes of wire between the isolator and the coach battery, 2 soldiered and 2 twisted connections.

Just like Bob I went with 4ga and one piece. Afterwards 14.5 at the battery and 14.7 at the alt

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I guess the question is how many times did you find your battery dead because it did not receive a good enough charge from the 65 amp alternator?

None.

John Mc

88 Dolphin 4 Auto

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I remember when I got my Escaper, only 12.3v at the coach battery. Started repairing things and found 4 different sizes of wire between the isolator and the coach battery, 2 soldiered and 2 twisted connections.

Just like Bob I went with 4ga and one piece. Afterwards 14.5 at the battery and 14.7 at the alt

Yes and that to me is a better upgrade then a 130 amp Alt.

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I got my problems sorted out and decided that I did not need a larger alt.

It turned out that I had a couple of problems that I did not know about.

1-one year old solid state isolator does not work at all.

2-8 gauge wire from isolator to coach battery.

3-8 gauge wire from isolator to truck battery.

4-6 gauge wire from alt to isolator

5-bad connection at alt.

6-bad ground in the coach.

After a pile of sorting things out, I am now getting a good charge at both batteries and have not had a problem with charging anything.

The solutions- I replaced all of the wire with 4 gauge wire w/crimped and soldered lugs, new relay type isolator, checked voltage lose at front and rear batteries and it is much less loss than before the heavier wires.

Before all of the changes, I had 14.5 volts at the alt, 13.? at isolator and only 12.7 volts at the truck battery and 12.5 volts at the rear battery. Thanks for all the help with eventually getting things working right.

You could go broke if you had to pay someone to do all of the work on these 25 plus year old vehicles.

On top of the isolator not working a solid state isolator requires a .7 volt break over voltage to work so the loss to the rear battery all ready starts out with a .7 volt deficit before it goes any where.

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Yes and that to me is a better upgrade then a 130 amp Alt.

That is not an "upgrade." It is a "repair." RVs don't come new with the coach battery only reaching 12.3 volts and with wiring barely tied together.

Maybe you use words differently then I do. To me - to repair something is to get it back working as it did when new (in this case wired correctly).

To "upgrade" is to change part of the design to something regarded as better in some way then what was furnished by the company that built the RV or truck.

Since a large RV battery only needs around 1/2 amp to stay charged - it's obvious that a large alternator has other uses then just maintaining a battery are "float charge" level.

A large alternator is certainly a good upgrade for those that have a need for it.

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A large alternator is certainly a good upgrade for those that have a need for it.

Personally, I don't believe any Toyhouse user would derive any tangible benefit from the high current alternator, there are less expensive alternatives that would serve the application in a more efficient manner.

Although everyone has their own opinion on installing a high current alternator upgrade, IMHO, I believe I've only seen one case on this forum where the user would benefit from an upgrade, and even then, I believe he would have been better served by installing a genny.

If I remember correctly, he had a couple battery operated scooters that needed to recharge while traveling, and was using a high power inverter to run the battery chargers. I seem to recall in that thread that he also needed to upgrade the wiring, probably to a #0 or even #00 to handle the current without a corresponding voltage drop. I believe we also explored the addition of a genny as another option.

Even in my case, where I use the trucks alternator as a "genny" to recharge my coach battery when I'm parked for extended time, a few days. Rather than spend the money to upgrade the alternator and wiring to accommodate this usage. I would probably be better served to buy a small honda, and when parked for couple days and need to recharge the coach battery,, use the honda rather than start the truck.

Not a perfect solution, but an acceptable solution.

ALSO - Regarding Upgrade vs Repair. Mix of words.... poor quality connections may be acceptable in a low current application and could go undetected for years. Then when we start trying to run high current thru those connections, we see large voltage drops that become unacceptable.

However, if one does a high current upgrade, part of that upgrade needs to be the wiring if they are to derive the full benefit of the added current capability.

With that said, the goals of this forum are education, information, exploring ideas and alternatives. I believe that is served in every single post that I've seen, regardless if I agree or not. :-)

John MKc

88 Dolphin 4 Auto

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With all this high amp alternator stuff flying about. I hope everybody remembers that batteries have a MAX SAFE charging rate and exceeding that too often will reduce battery life.

Most of the vehicles that come with larger alternators do so because they have large loads (radios, winches) to power , not to charge batteries.

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. I suspect in part the problem with this discussion is a bit of ignorance. An alternator/regulator is only going to charge a battery at the rate it needs -so size-of-alternator versus size-of-battery-bank is a non-issue. I can't figure why some people get upset about the concept of installing a larger alternator. If someone doesn't like it - then the best advice is do not do it.

I also fail to comprehend why some , e.g. Waiter, feel that no "toyhouse user would derive any tangible benefit from the high current alternator." What does being a Toyota have to do with this? A RV is an RV. Either someone wants to use X amount of applicances or they do not. It's a matter of personal preference how many are used and how they are powered. If some Toyota RVs benefit from using a stand-alone fuel-driven generator - then certainly using a main-engine driven alternator can also be useful to some people.

As WME stated - large alterntors (140-200 amps) are common nowadays on cars, trucks, and SUVs to make more power at low engine speeds to run high loads and NOT for the max amps or increased battery charging. My 2002 Dodge Caravan came from the factory with a 160 amp alternator. On the other hand, RVs and emergency vehicles often have large battery banks that CAN benefit from more amps of battery charging. and many also have large DC to AC inverters.

Factory equipped Nippo Denso alternators on 70s-80s Toyotas only charge around 25-30 amps at engine idle speed. A 140-160 amp Denso or Delco CS series will charge 50-55 amps at engine idle speed.

In my case -I've got three RVs with large alternators and no stand-alone generators. I prefer it that way since I do not want the extra weight or space taken by one. If I had a need for AC when camping -I might feel differently -but I don't. The most recent RV I added a large alternator to is my 1978 Toyota Chinook. Having the large alternator allows me to run a microwave oven without having a stand-along generator. It also allows me to recharge my two large "house" batteries quickly with the engine idling. Someones when I've been using my 3000 watt inverter - the batteries get quite run down. My 140 amp alternator charges 55 amps with the engine idlling. The OEM Toyota Denso 45 amp alternator only charged 25-30 amps at idle speed.

I also do not buy the claim about larger alternators being expensive. A brand new 140-160 amp alternator can be bught for $90 and a used one cheaper.

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There are a select few that have a need for a large charging rate big battery banks etc. most will never use the extra current. By increasing the wire size one would be able to take advantage of the stock alternator's output to provide power to the coach battery by an appraisable amount most modern Toy home size charger/converters are in the 35-45 amp range and they do an excellent job charging even two batteries. Using a 4 or 6 cylinder 100+ HP engine as a stationary generator to make 1600 watts is not the most efficient method of power production.

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In the case of emergency vehicles cop cars ambos and modern family vans the large alternators are to keep up with the power demands that the battery alone can not. Running A/C units (plural) 100 watt two way radios strobe lights and other gadgets that is a perfect example of need.

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JD,

That was the point, "Toyhouse". If you have a 40 ft diesel pusher, sure, you'll probably benefit from a 120 amp alternator, is that enough?

But a Toyota pickup with a 21 ft house on its back, not so much. The 55 amp stock alternator will serve the vast majority of the cases just fine.

Exceptions, yes, there will be. Thats what this discussion is about. And of course, personal; preference will be the trump card. Something may not make sense to me, but if JD or anyone else want to slap a 120 amp alternator to their Toyhouse, Have a ball.

The goal of theis forum is to exchange ideas, information, experience, and yes, even opinions. As I said, IMHO - Your wasting your time and money, but hey, its your time and money to do your bidding.

JOhn Mc

88 Dolphin 4 Auto



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A larger alternator certain can provide "tangible" benefits to some users regardless if your RV is 16 feet or 40 feet long.

As stated many times already - it provides higher amps at low speeds. That allows a high charge rate with the engine idling instead of having to rev it up. That is convenient when you've got a half discharged battery bank you want to charge back up - and you're in a campground with "neighbors.".

Having a large alternator also takes up the slack that a battery bank lacks in amps when running high draw appliances via a DC to AC inverter. It allows me to use a microwave oven at full heat being powered by the "house battery" and the truck engine idling. For my use - it elimnates the need of having a separate stand-alone generator.

Does everyone need one? Heck no. Same goes for a refrigerator, a stand-alone generator, or even an RV of any sort. Different users have different needs and/or wants. Several brand new 20 foot RVs (not 40 foot) are coming with only the engine's alternator as the aux electric power source instead of a stand-alone generator. It cuts down on weight and the need to maintain a second engine. 160 amp alternators - like came OEM on my non-40 foot Dodge minivan - are even being use as electric welders via an add-on controller kit. 160 amp alternator makes a decent alternative to a stand-alone 2200 watt gen-set. Some of the new Roadtreks are coming with 2800 watt belt-drive alternators that can run the roof-top AC.

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Yes and that to me is a better upgrade then a 130 amp Alt.

this is a great point. wire gauge improvement helps eliminate voltage drop; unless you have a huge stereo or are using a pizzaz pizza cooker no need.

but to JDE's point, what if you want to fire up a full size air compressor>? I have several times and always have to fire up a genny or get extension cord because the crapola output of the stock alternator cannot supply enough juice to get the job done. Maybe someone wants to run a router or higher output microwave. I also agree with JDE; the reasons for high output alternator is to support heavy draw appliances/inverters... has 0 to do with charging batteries.

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WOW. I didn't mean to start verbal wars with this topic. As a newbe to RV's, I as wrong in thinking that I NEEDED more power from the alt. With the help of people here, I was informed through various topics that incorrect wire size, poor connections, improperly working or not working isolator, etc were robbing me of the available power of the stock alt.

As far as the upgrade or repair discussion goes, going from an inadequate wire size to the correct wire size, it now works so who cares which it is.

I would like to thank everyone for their comments on every topic that I have read for helping me hunt down and repair (or upgrade) my problems.

I have not done any extensive traveling since doing the repair but I am sure that everything will now work properly.

Thanks

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