L185 and 10si and 12si alternator upgrade wired correctly.

Oil pan 4

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Equipment
L185 turbo
Sep 21, 2017
412
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It may seem difficult because external voltage regulator alternators are a mess to wire but it's super easy to go to an internally regulated one once you remove the unneeded old alternator and voltage regulator wires.
To cut out the old alt and regulator you have to rewire the oil light and the alt light, if you want everything to work.
To start you cut out all the old 6 wire voltage regulator junk.
You do need to reuse and reconnect a few wires.
The alt and reg get their power from a small black wire with thin white stripe coming off a fuse, just pull this wire off the fuse terminal, you don't need it, the other end goes to the 6 plug.
There's a red wire coming off the 6 plug that splits and goes to the alt and oil lights, cut that red wire with a few inches to work with.
Take the red wire that you just cut, put a female spade connector on it and plug it into the now empty alternator fuse terminal, previously occupied by that black wire with white stripe.
The oil light is wired ready to go now and the alt light is half wired in.
The alternator light still has a thin white wire with thin red stripe that goes to the 6 plug. Cut this wire and extend it to the number 1 terminal on the alternator. If you buy a GM alternator plug it will be the white wire. Or if you are cheap and stick a spade connector on there it's the left terminal looking at the alternator from behind.
Take the alternator number 2 or right wire which should be red and connect it to the battery, this is your voltage sense wire. The dumb lazy red neck way to do this is to connect the voltage sense wire to the battery output terminal, I am guilty if this, did it many times when I was younger, running it to the battery is far superior to running it to the alt terminal.
Then take the alt output terminals or battery charge wire and hook it to the battery with at least a 10 gauge wire for a 10si and at least 8 gauge for a 12si.
If you do run the voltage sense wire to to alt battery terminal use a 6 gauge wire.
I'm doing it on mine right now, I will update in a few days if there is a problem like slowly draining the battery while off.

Hereis the original charge circuit before I ax murdered it.
Link from Russell king.
https://www.orangetractortalks.com/forums/attachment.php?attachmentid=48638&d=1587438463
 
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PitViper

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B1750HSD, TG1860, 5’ box, 6’ grader, 6’ rake, pond scoop, PHD, boom pole, winch
Apr 28, 2020
53
8
8
Decatur TN
Did you have any fitment issues? Were custom brackets or a different belt length required?
 

Oil pan 4

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L185 turbo
Sep 21, 2017
412
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Yeah I had to hammer on the belt tension bracket to make it fit.
I kept the same belt but it was kind of stretched out. A 10mm longer belt would probably fit.
 

PitViper

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B1750HSD, TG1860, 5’ box, 6’ grader, 6’ rake, pond scoop, PHD, boom pole, winch
Apr 28, 2020
53
8
8
Decatur TN
Thank you, I’m looking at upgrading the dynamo to an alternator and Kubota wants over $300 for the alternator that came on the California version of my tractor.
 

Oil pan 4

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L185 turbo
Sep 21, 2017
412
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$300? That's crazy.
And it's probably still not as good as a cheap internally regulated GM alternator that's been made since the late 1960s.
 

Dave_eng

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M7040, Nuffield 465
Oct 6, 2012
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Williamstown Ontario Canada
The best new alternator solution is a one wire DENSO.

Even GM is using DENSO alternators on their vehicles.

Come in many outputs and are smaller size than the GM's ones.

This one has 35 amp output for $59.

https://www.ebay.com/itm/NEW-CHEVY-...Lv5PairwiseWeb&_trksid=p2047675.c100005.m1851

60 amp for $105

https://www.ebay.com/itm/NEW-CHEVY-...RAREELECTRICAL&_trksid=p2047675.c100005.m1851

Dont go to too high an output as your drive will not be up to the load.

Typically 35 amp makes a big difference for most owners,

Dave
 

Oil pan 4

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L185 turbo
Sep 21, 2017
412
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1 wire is like preschool level.
The smaller kubota main drive pulley is smaller than what's typically found on a car and a typical kubota is RPM limited a lot lower than a car or truck.
I think I used an upgraded 12si I bought about 20 years ago that supposed to make like 90 a amps.
 

Dave_eng

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M7040, Nuffield 465
Oct 6, 2012
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1 wire is like preschool level.
The smaller kubota main drive pulley is smaller than what's typically found on a car and a typical kubota is RPM limited a lot lower than a car or truck.
I think I used an upgraded 12si I bought about 20 years ago that supposed to make like 90 a amps.
Preschool solutions are what many are looking for as they lack your electrical skills :)

When would you ever need 90 amps on a L185? Electric winch perhaps.

Dave
 

GreensvilleJay

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BX23-S,57 A-C D-14,58 A-C D-14, 57 A-C D-14,tiller,cults,Millcreek 25G spreader,
Apr 2, 2019
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re: When would you ever need 90 amps on a L185?

1) Add a electric/hydraulc snowplow...... LOTS of amps needed...
2) Tow a dump trailer with electric/hydraulic lift.....


I KNOW with #2...if you don't recharge the trailer battery from the tractor, it WILL go dead while trying to dump the heaviest load waaay outback ....:(
 

dochsml

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L4701HST
Jan 21, 2020
216
20
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Leonard, TX, USA
Preschool solutions are what many are looking for as they lack your electrical skills :)

When would you ever need 90 amps on a L185? Electric winch perhaps.

Dave
You're probably right, probably never 'need' a high amperage alternator on a tractor. But.... Need isn't the driving force of why people 'want' things. I certainly don't need a diesel truck. I don't even own a trailer, but I wanted it. The battery is going to supply the amperage to run whatever you hook up to it. It's just a matter of whether or not the alternator can recharge the battery before it's depleted. I wouldn't think that things like a winch would be running nonstop for long periods of time. A small battery would be at least 20AH with most being larger. If you ran a 90 amp winch for 10 minutes straight without letting of the button for even a second, you would have consumed 15AH from the battery (without the tractor running). If the tractor was running, the alternator would minus away from that 15AH a little bit. I think the big thing here is how long are you going to hold that winch button in and how quickly do you want your alternator to recharge that battery afterwards? To sum up (without letting the battery go below 50% charge), if you had a 20AH battery and a 20 amp alternator, you could hold the button for somewhere between 6 and 7 minutes before needing to let the alternator recharge the battery for 30 minutes. I could see where if someone was doing a lot of winching, this would be a pain.
 

Oil pan 4

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L185 turbo
Sep 21, 2017
412
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I used to do 1 and 2 wire 12si alternators too. But going to 3 wire isn't difficult once you know what the 3 wires do. I promise it's super easy and you don't have to use the 3rd wire but I did I want the alt warning light to work.

I have my little 4,000lb winch I may need to use.
I do have big lights installed, I chopped the factory headlights to use 100w each H3 bulbs. I have a roll over protection bar to install and I will put a big light bar on that.
So with the head lights and light bar on I will be a little over 20 amps.
May need to jump start or charge a big tractor or pickup battery with my little kubota.
Probably get a sprayer at some point.
I'm also rebuild the battery box to be a big as possible, once the group 65 size battery in there now dies I'm going to put the biggest deep cycle marine battery or batteries that will fit in my battery box.
 
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GreensvilleJay

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BX23-S,57 A-C D-14,58 A-C D-14, 57 A-C D-14,tiller,cults,Millcreek 25G spreader,
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Greensville,Ontario,Canada
I prefer to use the newer CS130 series of alternators. Smaller, more amps and FREE... Just remove for any scrap GN car..but be sure to get the mating connector.
 

Oil pan 4

Active member

Equipment
L185 turbo
Sep 21, 2017
412
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Well that alternator finally died.
My guess is brushes or voltage regulator, or it got rained on 1 roo many times. I'll stick my 10si of shame on there, while I figure out the 12si. The 10si it was my spare alternator for years, probably had it since the late 1990s.
You can test everything but the voltage regulator with a multimeter.
So take it apart, check the triode, bride rectifier, brushes/slip rings and field windings.
Then if everything checks out, change the voltage regulator.