Upgrading stock alternator to 130/150 amp (1 Viewer)

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Last weekend I got the defective alternator replaced and installed the new reman (BTW the local Toyota dealer tried to gave me hard time with both the warranty and the replacement, but a fine gentleman at the parts dept. helped to sort things out-caveat emptor).
After driving the rig 80 or so miles at soaking heat, I can finally say that everything runs fine. No more voltage surge!.
I'd also like to suggest a minor modification to the bracket as per the attached pic. By shortening the adjusting wall around 15mm towards the engine block (pls see the red line) will clear the head of the adjusting bolt from the steering pump hose and therefore making the adjustment very easy-just an idea for continuous improvement.
Last but not least. Is there anyone running this same mod but with longer (½ inch?) non-OEM belts? If affirmative, please share your experience as I do not see how these belts can be replaced without R/R the whole thing again-not only a PITA but incredibly difficult, if not impossible, at the trail. This is the only negative impact of the mod. I'll dig on Gates and Mitsuboshi catalogs...we'll see.
All and all, I'm another Photoman's mod happy user
Thanks y'all for your help.
Cheers!
fj80pb
upload_2016-8-1_22-58-6.png
 
Somewhat silly question - how hard is it to remove the stock alternator with good tools and a helper? Got our voltage light on, suspect it's the battery, but will probably do alt anyway just to do it.
 
It is a bit of a pain IIRC. Better to remove battery and battery box for access. I had an almost seized a/c compressor tensioning bolt, so check to make sure yours is free. Getting the new belts on was a pain as well. I also upgraded the alt wire, added a mega fuse, and rewired for dual battery keeping the original battery for starting duty only.
 
It is a bit of a pain IIRC. Better to remove battery and battery box for access. I had an almost seized a/c compressor tensioning bolt, so check to make sure yours is free. Getting the new belts on was a pain as well. I also upgraded the alt wire, added a mega fuse, and rewired for dual battery keeping the original battery for starting duty only.


Fortunately, removing the battery and battery box and moving the power steering reservoir are all fairly easy. Are the bolts easy to get to, the ones on the alt? Do you have pics of your setup?
 
Hi there.
This thread provides all the info you'll need to either change the stock 80 amps or swap to the Tundra/Sequoia 150 amps alternator -which I highly suggest. @Photoman makes a brilliant bracket that will allow you to almost doubling the amps while staying OEM: get your hands on one of those before it's too late.
Either case I recommend facing the job with positive karma and patience-accessing there isn't fun. No special tools needed and, as far I'm concerned, the bolts aren't that difficult to get to (although you want an impact gun to remove/install the pulley and a pin-removal to upgrade the connector if you get the 150 amps alt). If your rig is lifted, I also suggest getting a wheel step (unless you are very tall). I'm 5-11 and this thing is really useful to work on the engine bay-at least for me.

Ironton Truck Service Step — 300-Lb. Capacity | Steps| Northern Tool + Equipment

And don't forget replacing the belts as you already dealing with it.
This is a nice weekend project...at leisure speed and between:beer:. Good luck!
Cheers

fj80pb
 
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I pulled the trigger on the bracket and smaller pulley. @Photoman was extremely pleasant to deal with and shipped one on very short notice.

Now I need to decide what alt to buy. I want the 150A alt from the Sequoia - should I go reman from some random manufacturer, salvaged OEM part, or should I spring for a reman Denso on ebay? Thanks.
 
Mine from the salvage yard is going on five plus yrs.
 
Can I reuse my old harness for awhile?

A brief update - the old alt is out.

I first crushed and crumbled every important connector on my harness (they broke immediately), but I wasn't too upset about it. The one to the distributor cap doesn't seem to need the locking tab. The one that was in the alt was quite brittle. The bad news is that I destroyed it. The good news is that the pins I needed to extract from the connector popped right out and are ready to go into my new connector.

A few things to note - the top bolt (pivot bolt) is the only one you have to really lean on to get it started. Your tensioner bolt is best removed with a ratcheting wrench with a swivel head (like a gearwrench). It is not hard in the slightest, but it's a long bolt with a fine thread pitch so you'll be at it for awhile. At some point your belts will loosen sufficiently that you can gently pry them off with your finger and give yourself a little more room. Then you remove the final bolt, the lock bolt. Mine was finger-tight. Rock the alternator back and forth a bit and it'll start to swivel. Once the top pops free you're in for some real fun trying to figure out how to get it out. I managed to get it between the two hoses from the power steering reservoir.

Now I have to remove the old bracket. Still not entirely sure how I'm going to install the new one, but I'll get to that when I get to it. The power steering hose is very much in the way of pulling the bolt out. The old bracket is out but the power steering hose is in the way of the new bracket. Can I undo the 22mm bolt and redo it?
 
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Minor disaster -
8QEPfqK.jpg



I had difficulties getting the lower bracket bolt out. I managed, then realized that I had no hope of making new new bracket fit - I resolved to just loosen the power steering bolt a bit so I could turn the hose slightly. And out it came, spilling everywhere. Goodbye, power steering fluid.

Now, when I look at it, the power steering hose will be very tightly in contact with the new bracket. In the FSM, it says that the "tab" of the power steering hose ought to contact the tab on top when I install it. I don't see how that's possible with the new bracket. Do I bend the metal part of the hose? Suggestions?
 
whats the normal amperage of a stock LC alternator? if one was to upgrade to a higher amp alt. what are the advantages? is there different mounting brackets one needs to get to install a higher amp alt?
 
whats the normal amperage of a stock LC alternator? if one was to upgrade to a higher amp alt. what are the advantages? is there different mounting brackets one needs to get to install a higher amp alt?

1. Depends on the year. My '97 had a 90A alt.
2. You get more power, which may or may not be an advantage to you. It's an advantage if you run a ridiculous electrical load, such as a giant stereo, or you're winching all day, or you have like four refrigerators.
3. Yes, PM @Photoman, he makes them and does a very good job of it.
 
I also run an electric compressor that takes 30A so another reason to upgrade alternator.
 
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I have yet to do Bills pulley which means I make lower amps at idle than a stock alt. I haven't found this to be an issue yet though so I'm dragging my feet on doing it. I've run an edgestar 63qt along with several devices charging, 3 phones, a tablet, a laptop. Along with 2 sony 800W amps and a kenwood 500W mono. I've also ran the winch concurrently with all the other junk running plus a couple of million candle power hand held spots with no issues. I'll be putting in a Viair compressor in the next month or so and have no doubt about the charging system what so ever.

This is one of the best and cost effective (cheap) mods I've done on my pig.
 
1992 3FE. Pretty sure stock size alternator. Not sure what the amps are.

How do I determine if I really need a larger alternator? Here are my planned adders. (I am planning dual batteries).
1. 800 Watt inverter
2. M8000 Warn (already connected)
3. Fridge (someday down the road)
4. Floods and Spots on front bumper
5. CB
6. GPS (someday down the road)
7. HAM (someday)
8. No major stereo gear (touch screen head unit and 4 speakers-no amp)

I'm a scenic drive adventurer. I dont anticipate using the winch a lot.

Electrically I'm not sharp but I'm reading a lot..... I get that amps are amps and I need to add what I have and see but am I trying to only 80% of my alternators capacity or can I soak it all up?

Appreciate any thoughts or locations of threads that get into this.
 
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you can do the math for the added accessories in order to determinate how many extra amps they should put in your electrical system .. or the most simple and accurate way ..

measure your load after it's already installed and on ..
 
you can do the math for the added accessories in order to determinate how many extra amps they should put in your electrical system .. or the most simple and accurate way ..

measure your load after it's already installed and on ..
Thanks. Does anyone know the stock amperage on the 3FE alternators?
 
80 amps from memory. Mine tested at 86 when it was rebuilt by a local electrical shop
 
80 amps from memory. Mine tested at 86 when it was rebuilt by a local electrical shop
That's the best I could get from looking around online. I cant imagine getting beyond that.

Thanks
 
Joesy1972
The first thing to know about alternators is that many are made to operate for a limited time at their full capacity.
Think of it in the terms of a vehicle, there are plenty of cars that can attain over 100 MPH, but likely won't last as long if operated at their maximum speed all day.
Your list of anticipated loads has two large demands for your original alternator.
The inverter calculates out to over 66 amps at full output (800/12).
Winch ~ 300+ amps - albeit short term use.
Fridge and other items not too big, although if you are parked camping for several days and have pulled a lot out of your dual battery setup, the alternator is going to have a big job recharging the two batteries.
Speaking of batteries, if you haven't already researched them you will want the starting/deep cycle combination style.
A dual battery setup with properly sized cables, isolator, high capacity switches and charge monitoring is not cheap.
The Blue Sea System Circuit Wizard is a great app for finding your cable sizes. One feature I like is it is can calculate the effect of increased temps of under hood operation with the 'Installed in Engine Room' calculation.
You will need to increase the cable size from the alternator to the battery and install a higher amperage fuse.
I installed new fusible links while in there, not required but a good idea on a 20 year old truck, and 175A fuse for alternator to the battery.
If you are doing this yourself I think I have the P/Ns. There was a post on mud by an engineer that had figured out the fuse with the proper characteristics.
And of course you will need Photoman's bracket!
I run the Toyota 150 A alternator with a Sears P-1 Platinum group 65 Battery from Diehard, supposedly built by Odyssey, held in place with an Artec battery mount.
I think you can fit one size larger than the P1.
Plenty of stuff to figure out and gather up for a top notch system.
 

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