Alongside the high current drawing ECU also have two batteries to keep fully charged. One of those batteries powers the electric winch and a few other add ons, so the high amp alternator is mainly to keep that nicely topped up.
12 volt BJ70 alternator upgrade?
- Thread starter 1985bj70
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Alongside the high current drawing ECU also have two batteries to keep fully charged. One of those batteries powers the electric winch and a few other add ons, so the high amp alternator is mainly to keep that nicely topped up.
sorry it was more a general question, i also have two alts in my pzj77, a 12v one and also the stock 24v alt.
the ecu in my lj78 is a small metal box the size of my hand, with no heatsink, so i cant imagine it drawing much more than one or two amps? i dont know... im no expert lol
the ecu in my lj78 is a small metal box the size of my hand, with no heatsink, so i cant imagine it drawing much more than one or two amps? i dont know... im no expert lol
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Hey 1985bj70. Here are some pics of my upgraded alternator install.
I ended up using one the the double alternator belts to run the new alternator.
My water pump still uses the two belts but my old alternator only has one now which should be okay as it is only driving the vacuum pump.
The charging system charges at 14.8 volts now which is a pure delight. I loaded the system up and achieved 254 amps at 13.8 volts.
Hope this gives you some ideas.
Take Care
I ended up using one the the double alternator belts to run the new alternator.
My water pump still uses the two belts but my old alternator only has one now which should be okay as it is only driving the vacuum pump.
The charging system charges at 14.8 volts now which is a pure delight. I loaded the system up and achieved 254 amps at 13.8 volts.
Hope this gives you some ideas.
Take Care
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Looks like a Greens alternator??
crushers
post ho
i am on this path now with the BJ70 refurbishing.
i started a thread about finding vacuum pumps that work independent of the alternator for the 3B and am getting some nice feedback.
i asked my local electric guru about the mean green and it seems that heat is an issue. just what i have heard.
i am looking at a lexus alternator with remote vacuum.
subscribed.
i started a thread about finding vacuum pumps that work independent of the alternator for the 3B and am getting some nice feedback.
i asked my local electric guru about the mean green and it seems that heat is an issue. just what i have heard.
i am looking at a lexus alternator with remote vacuum.
subscribed.
It's not a greens alternator. This alternator is from quality power.
They take a small body Nippon Denso "hairpin" alternator and re wind the rotor to achieve 200, 250 and 320 amps. DC power engineering has an excellent write up under Tech info (DC Power vs "The Competition).
They explain how hair pin alternators excel in the industry with some great info on all alternators. Dc power are the go to guys if you can spare the cash.
Crushers, hair pin alternators are the latest and greatest. The small and large body alternators come in lots of vehicles, Cadillacs, pt cruisers Highlanders ect. The run dual internal fans, a condensed stator, the rotor produces the amperage and the regulator is on the out side of the case so it doesn't get heat soaked.
If your retrofitting an alternator from another vehicle I do suggest a smaller pulley. Almost every one sells one. It helps with a higher charge at lower rpm's.
My 2 cents anyways.
Take Care.
crushers
post ho
all advice is accepted and appreciated.
cheers
cheers
crushers
post ho
got a part number?
we pulled out the golden book and reviewed a bunch of different alternators. we found one that said "140 amps" so we ordered it in. the mount would take a bit of tweaking, the old style coarse spline vacuum pump would have bolted right up
but
on the box it said 80 amp
and when we spun it up by hand the alternator was making noise so we never did run it up.
kinda sad when you buy new and recieve s***.
part number would be nice Spallet.
we pulled out the golden book and reviewed a bunch of different alternators. we found one that said "140 amps" so we ordered it in. the mount would take a bit of tweaking, the old style coarse spline vacuum pump would have bolted right up
but
on the box it said 80 amp
and when we spun it up by hand the alternator was making noise so we never did run it up.
kinda sad when you buy new and recieve s***.
part number would be nice Spallet.
- Thread starter
- #31
Sorry pradocruzer, I am subscribed to this thread but never got any email notification. Nice work, 250+ amps also, damn! That is the output of the one alternator that you added on? Not looking to do the same job on my truck are you? 
Just what you wanted, more work on someone elses truck, right?
Just what you wanted, more work on someone elses truck, right?
Sorry pradocruzer, I am subscribed to this thread but never got any email notification. Nice work, 250+ amps also, damn! That is the output of the one alternator that you added on? Not looking to do the same job on my truck are you?
254 amps is the output on the alternator I just installed, yes. High amp output is great and all but you need to sustain high voltage at the same time. I like to see mine above 14 volts. At 200 amps the alternator produces 14.2 volts and then drops off fast to 13.6-13.8 at the rated 254 amps. In my mind it is only good to 200 amps.
I would love to but unfortunately I do not have any time to do a fab project right now. I may at a later date. I work on every ones elses cars all the time that's the problem.
Take care
- Thread starter
- #33
Gotcha, I am more concerned at maintaing a decent voltage level also, as my amp goes in and out of protection mode due to the voltage level dipping too low. Maybe down the road I can talk to you again about this project. Cheers.
crushers
post ho
interesting read ...
you have tried this, correct?
why do you want a smaller pulley? is the alternator not up to snuff?
you have tried this, correct?
why do you want a smaller pulley? is the alternator not up to snuff?
You need to have the correct ratio between the crank pulley and the alternator pulley when your retrofitting an alt from another vehicle. If the alternator is not driven fast enough at idle to meet it internally set turn on voltage you will have light surge. An example on mine is at 750rpm I'am charging 13.8 volts and when I bring the rpm up to 800 rpm I achieve it's voltage set point and it charges at 14.8. This is only really visible at night. All alternators have sightly different set points for the vehicle they are in from the factory so a smaller pulley can solve the problem of light serge and low system voltage at idle with out increasing engine rpm's.
My pulley ratio was okay as the increase of 50 rpm was not a big deal.
Take Care.
My pulley ratio was okay as the increase of 50 rpm was not a big deal.
Take Care.
