L175, L185 rewire

Oil pan 4

Active member

Equipment
L185 turbo
Sep 21, 2017
412
107
43
NM
When I pulled off the control panel to replace the steering box I found some burned wires and rubbed through wires. It's the glow plug wires of course are burned and some others, might have been head light wires.

Since I switched over to a GM 12SI alternator I don't need most of the 6 wires that went to the voltage regulator. There are other dead end wires and plugs under the dash too that can go.
I also replaced the almost useless 35w original headlight bulbs with 100w H3 bulbs, so the original headlight circuit is useless now that I'm running about 3 times the amps on it.





 

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Oil pan 4

Active member

Equipment
L185 turbo
Sep 21, 2017
412
107
43
NM
Cut out one rats nest worth of wires that never went to anything, went to the external voltage regulator and went to the head lights.

 

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Russell King

Well-known member

Equipment
L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
Jun 17, 2012
4,603
975
113
Austin, Texas
I just replaced the wiring harness on my L185 with one I bought from the dealer awhile back.

They do have some odd unused accessory wiring that is unused. Green and one blue with white stripe. Green was for flashers/turn signals at rear. Can’t figure out what the blue/white was for but it ran up by where the glow plugs connect to the wiring harness. Any ideas what it was.

The headlight wiring was orange and brown and circuit was fairly obvious through the fuse box and key switch. There is also a black ground wire that runs off the alternator/regulator to the mounting bolt on the headlight.

It all started with replacement of the bad starter and found poor alternator then progressed to the regulator replaced that lead to butchered wiring under the dash by others that I just couldn’t stand to leave alone.

Unfortunately the new harness is a bit different than the existing one so I am down a wormhole trying to figure out why it is different and why they drew poor schematic diagrams and published them in the operator’s manual.

If you need a schematic let me know, I have a few. But ignoring the regulator wiring and accessory wiring there is little left under the dash.


Sent from my iPad using Tapatalk
 

Oil pan 4

Active member

Equipment
L185 turbo
Sep 21, 2017
412
107
43
NM
For modifications I'm going to at the very least add my 100 watt H3 head lights, an amp meter, a volt meter, gauge lights for those gauges and some provisions for power to the back end.
 

Oil pan 4

Active member

Equipment
L185 turbo
Sep 21, 2017
412
107
43
NM
I just replaced the wiring harness on my L185 with one I bought from the dealer awhile back.

They do have some odd unused accessory wiring that is unused. Green and one blue with white stripe. Green was for flashers/turn signals at rear. Can’t figure out what the blue/white was for but it ran up by where the glow plugs connect to the wiring harness. Any ideas what it was.

The headlight wiring was orange and brown and circuit was fairly obvious through the fuse box and key switch. There is also a black ground wire that runs off the alternator/regulator to the mounting bolt on the headlight.

It all started with replacement of the bad starter and found poor alternator then progressed to the regulator replaced that lead to butchered wiring under the dash by others that I just couldn’t stand to leave alone.

Unfortunately the new harness is a bit different than the existing one so I am down a wormhole trying to figure out why it is different and why they drew poor schematic diagrams and published them in the operator’s manual.

If you need a schematic let me know, I have a few. But ignoring the regulator wiring and accessory wiring there is little left under the dash.


Sent from my iPad using Tapatalk
Yes I had the same unused wire ran over by the glow plugs. I think it could have been for a fuel shutoff solenoid or fuel pump.
The orange and brown wires were melted.
It looks like a lot of things little things were ran unfused.

Yes please post up that schematic. I think I marked everything from the control panel but it's good to double check and a few things were wired up oddly.
I have a free fuse block space now, I think it went to the headlights.
 

Russell King

Well-known member

Equipment
L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
Jun 17, 2012
4,603
975
113
Austin, Texas
The headlights actually tied up two fuses out of four on my fuse block. One for high beams (orange?) and one for low beams (brown?). The other two were for the black/white to the alternator and some rear light or accessory.

Hopefully I got two diagrams attached one for charging circuit to show it simply, and an overall wiring schematic.

Charging circuit:
View attachment Charging Circuit.pdf
Overall below:
View attachment L185 from WSM.pdf


Sent from my iPad using Tapatalk
 

Oil pan 4

Active member

Equipment
L185 turbo
Sep 21, 2017
412
107
43
NM
That's why the headlight circuit didn't make any sense. Mine had single function bulbs installed.
Never had flashers, or a work lamp.
Looks like the glow plugs come on during starting.
 

Oil pan 4

Active member

Equipment
L185 turbo
Sep 21, 2017
412
107
43
NM
I hole sawed a place in the right side next to the steering wheel and installed the amp meter.
Took the head light wires that came off the ignition switch and slaved them to run relays. The head lights are just going to be 100w H3 bulbs put in my hacked kubota lights.
Ran wires straight off the amp meter to the old head light fuses.
I'm making the dash removable by using some new random 6 pin and Jack plug I found in my junk collection wired up with 14 and 16 gauge wires.
 

Oil pan 4

Active member

Equipment
L185 turbo
Sep 21, 2017
412
107
43
NM
The random plug I found in my junk collection was a Ford trailer brake controller harness.
I had trouble finding something that was unplugable and able to handle 60 amps so i could send power from the alt, to the dash where the amp meter is then back to the battery. I found a 50 amp Anderson plug with 8 gauge pig tails in my junk.
 

South 40

Active member

Equipment
L1500DT, 750 Ford backhoe, 49 D4 Cat Repowered with 6.9L Diesel
Nov 12, 2012
168
52
28
Bloomsdale, Mo. USA
Hi Oil Pan,

I just started the same project, already ripped out the old harness and will make my own.

Where did you get your amp gauge, did you upgrade the bulb sockets, do you have any pics of your progress/finished handy work?

I have an idea of what I want to do, but am open to suggestions, and good pics of how other's have already done this, :)

Cheers
Samantha
 

Dave_eng

Well-known member
Lifetime Member

Equipment
M7040, Nuffield 465
Oct 6, 2012
5,106
926
113
Williamstown Ontario Canada
Hi Oil Pan,

I just started the same project, already ripped out the old harness and will make my own.

Where did you get your amp gauge, did you upgrade the bulb sockets, do you have any pics of your progress/finished handy work?

I have an idea of what I want to do, but am open to suggestions, and good pics of how other's have already done this, :)

Cheers
Samantha
For my money you will do better with a volt meter rather than an amp meter.
Now you do not have high current flowing thru a meter.
For modern vehicles with warning lights instead of gauges, the idiot light is really a voltage signal.

Dave
 
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South 40

Active member

Equipment
L1500DT, 750 Ford backhoe, 49 D4 Cat Repowered with 6.9L Diesel
Nov 12, 2012
168
52
28
Bloomsdale, Mo. USA
Hi Dave,

Yeah I think that is how I will go. I have a few ideas where I might just stick with the idiot light, but would just prefer being able to monitor just what is going into the battery rather than OK it's charging.
The new alternator I just got is just a 1 wire, so my options are limited, but a volt meter will be less heavy duty wire to run.

Thanks for the replay and suggestion, much appreciated!

Cheers
Samantha
 

john ronning

New member

Equipment
L185dt kabota, 155dt yanmar
Dec 13, 2022
2
0
1
Oregon
Hi Dave,

Yeah I think that is how I will go. I have a few ideas where I might just stick with the idiot light, but would just prefer being able to monitor just what is going into the battery rather than OK it's charging.
The new alternator I just got is just a 1 wire, so my options are limited, but a volt meter will be less heavy duty wire to run.

Thanks for the replay and suggestion, much appreciated!

Cheers
Samantha
Hello, i'm starting my l185 rewire. Going with internal regulator alternator. 1 wire or 3 wire? Concern about high enough rpm to entergize. Recommendations and tips appreciated. Thanks
 

Dave_eng

Well-known member
Lifetime Member

Equipment
M7040, Nuffield 465
Oct 6, 2012
5,106
926
113
Williamstown Ontario Canada
Hello, i'm starting my l185 rewire. Going with internal regulator alternator. 1 wire or 3 wire? Concern about high enough rpm to entergize. Recommendations and tips appreciated. Thanks
This is my recommendation. 35 amp DENSO one wire.
Denso
Reasons: Size, i.e. form factor is small making it easier to find room for it.
DENSO is a name known world. My friend has a 2011 Buick and its original alternator is DENSO not DELCO.
The rpm to energize seems to be a situation those converting an old DELCO 10 SI to one wire operation run into.
Stick with an output around 35 amps so as to not tax the drive belt.
Dave
 

john ronning

New member

Equipment
L185dt kabota, 155dt yanmar
Dec 13, 2022
2
0
1
Oregon
This is my recommendation. 35 amp DENSO one wire.
Denso
Reasons: Size, i.e. form factor is small making it easier to find room for it.
DENSO is a name known world. My friend has a 2011 Buick and its original alternator is DENSO not DELCO.
The rpm to energize seems to be a situation those converting an old DELCO 10 SI to one wire operation run into.
Stick with an output around 35 amps so as to not tax the drive belt.
Dave
Thanks, Dave. Understand these alternators are also in Toyotas and small Ford trucks. Be nice to get rid of all those junk wires