Re-wiring a gas 450...questions

The wiring on Charlene is pretty much toast...i mean crispy and black. Not interested in buying the harness, wanna do it one wire at a time.

What gauge(s) will I need, and approximately how much wire will I need? I've replaced the battery cables, so don't need info for them.

Thanks all.
 
You are wanting to rewire your 450 the hardest way possible and way least likely to work correctly. Bet
you want to use all one color and size wire too so it's impossible to trace wires.

Buy a complete new harness from Brillman, Agri-Services, etc, or any of the Case/IH dealers that cater to
tractor restorers. They use the proper well crimped connectors, proper colors and sizes of wire,
everything properly marked to install correctly.

My Super H had the factory wire harness when we bought it in 1968. Cloth covered rubber insulation.
Insulation would crumble in your fingers if you touched it. About 1980 I had a complete replacement
harness (only 4 wires in it) made by the OEM supplier of harnesses used by the Farmall Plant. They used
PVC insulated wire with colors per the factory, I sent them prints. The OEM harness was junk in 26 years.
The replacement harness is 38 years old and still perfect! Your 450 has the same type of wiring that I
replaced 38 years ago.

Sometimes You get More than what you pay for!
 
Agreed. If you need it a complete wiring harness is the way to go - why reinvent the wheel? I have a 350 that is getting a new wiring harness this spring - I wouldn't even consider wiring it from scratch.
 
I've rewired several Farmalls in the past,and one Oliver,couple of John Deeres and lots of Fords,not counting the old cars and trucks.Use # 12 wire and you will
be fine except for the main wire for the amp gauge that should be a # 10,use different color wires to make it easier to trace,do one wire at a time so you don't
make mistakes on routing.You can save money and it's what restoration or hot rodding is all about.I like to solder and use heat shrink on the connections,if you
crimp make sure you have a good crimping tool,not the flat crimp cheap models that are sold with most kits.
 
(quoted from post at 22:09:11 01/31/18) The wiring on Charlene is pretty much toast...i mean crispy and black. Not interested in buying the harness, wanna do it one wire at a time.

What gauge(s) will I need, and approximately how much wire will I need? I've replaced the battery cables, so don't need info for them.

Thanks all.

The owners manual has a very good wiring schematic, but I'm not sure if it gives the wire sizes. Basically you will want 10 gauge for the charging system and probably 14 gauge for everything else. For the length, get out your tape measure and make some guesses. I personally have never bought a wiring harness for anything.
 
Buy a 50' roll of 14 ga.(10 or 12 for the charging circit) in whatever color you like and a box of fittings,and get after it.After it is all 'rewired',wrap the whole thing in blacl tape to contain everything.while you are at it,throw the old generator/regulator away and replace with a one wire alternator.easy,simple ,trouble free,reliable.Have done 5 tractors in the method described.The next 'old tractor' will get the same treatment.
 
Three gauges are needed. 10ga for power circuits within the charging system, from charging system to amp gauge and from gauge to starter relay (solenoid). 12ga to the
light circuits and ignition primary (overkill but easier to work with). 14GA can be used for Field wires (with Generator) or
sensing exciting wires with an alternator, and dash light wiring. You need at least 7 different colors, or ID stripes on the
12gauge wire to identify circuits. and 2 colors for the 14ga. (the color ID requirement is difficult to achieve as most auto parts
stores have 4 colors) make a detailed map with color codes clearly marked. Wire tagging systems for end of wire indexing does not
work for rough and tumble weather exposed wiring. Jim
 
It depends on weather or not it is being wired back to original.
If a tractor is converted to an alternater a made up harness is
neater and better than regular harness.
 
The wiring isn't all that complicated on a 450. I've rewired Cubs, H's, M's and even a 240 from scratch and most of the wiring is short runs behind the instrument panel. The long wires run from the generator to the regulator, and IIRC there are only two of those.

For 90% of it you can follow the Bob M wiring diagrams for a letter series tractor. The main difference will be wiring up the gauges.

I run a 10ga white wire for the main battery charging wire, from the generator to the regulator to the ammeter to the hot post on the starter solenoid. Everything else is 12ga for simplicity.
 
Buy a wiring harness!!! About the time you buy all the different colored wires it should have, connectors, tape and solder all the connections at the ends of the wire plus your time, you will have more into the wiring then a complete harness will be. Next lets say you hook something up wrong and let the smoke out of an item or the wiring itself, you will be using not so nice of words for all the money that just went up in smoke. I have seen this before and saw a friend finally buy a harness to do the job right. If I ever had to do a rewire, I'm buying a harness and then adding a wire or two if I need to for anything extra I would have. If you want to do it right, the cloth tape works way better than the plastic tape. Sticks better and won't come loose like plastic does.
 
(quoted from post at 05:20:50 02/01/18) You are wanting to rewire your 450 the hardest way possible and way least likely to work correctly. Bet
you want to use all one color and size wire too so it's impossible to trace wires.

Buy a complete new harness from Brillman, Agri-Services, etc, or any of the Case/IH dealers that cater to
tractor restorers. They use the proper well crimped connectors, proper colors and sizes of wire,
everything properly marked to install correctly.

My Super H had the factory wire harness when we bought it in 1968. Cloth covered rubber insulation.
Insulation would crumble in your fingers if you touched it. About 1980 I had a complete replacement
harness (only 4 wires in it) made by the OEM supplier of harnesses used by the Farmall Plant. They used
PVC insulated wire with colors per the factory, I sent them prints. The OEM harness was junk in 26 years.
The replacement harness is 38 years old and still perfect! Your 450 has the same type of wiring that I
replaced 38 years ago.

Sometimes You get More than what you pay for!

I planed on using multi colors..fwiw.

I really want looking to drop $200 for wiring.... my first name isn't DR. ????
 
(quoted from post at 05:20:50 02/01/18) You are wanting to rewire your 450 the hardest way possible and way least likely to work correctly. Bet
you want to use all one color and size wire too so it's impossible to trace wires.

Buy a complete new harness from Brillman, Agri-Services, etc, or any of the Case/IH dealers that cater to
tractor restorers. They use the proper well crimped connectors, proper colors and sizes of wire,
everything properly marked to install correctly.

My Super H had the factory wire harness when we bought it in 1968. Cloth covered rubber insulation.
Insulation would crumble in your fingers if you touched it. About 1980 I had a complete replacement
harness (only 4 wires in it) made by the OEM supplier of harnesses used by the Farmall Plant. They used
PVC insulated wire with colors per the factory, I sent them prints. The OEM harness was junk in 26 years.
The replacement harness is 38 years old and still perfect! Your 450 has the same type of wiring that I
replaced 38 years ago.

Sometimes You get More than what you pay for!

I planed on using multi colors..fwiw.

I really want looking to drop $200 for wiring.... my first name isn't DR... lol
 
(quoted from post at 07:28:14 02/01/18)
(quoted from post at 22:09:11 01/31/18) The wiring on Charlene is pretty much toast...i mean crispy and black. Not interested in buying the harness, wanna do it one wire at a time.

What gauge(s) will I need, and approximately how much wire will I need? I've replaced the battery cables, so don't need info for them.

Thanks all.

The owners manual has a very good wiring schematic, but I'm not sure if it gives the wire sizes. Basically you will want 10 gauge for the charging system and probably 14 gauge for everything else. For the length, get out your tape measure and make some guesses. I personally have never bought a wiring harness for anything.

Rusty, that's a good idea... I'd forgot the manual has that. I'll need my reading glasses to decipher but good info there.. thanks.
 
(quoted from post at 11:08:49 02/01/18) The wiring isn't all that complicated on a 450. I've rewired Cubs, H's, M's and even a 240 from scratch and most of the wiring is short runs behind the instrument panel. The long wires run from the generator to the regulator, and IIRC there are only two of those.

For 90% of it you can follow the Bob M wiring diagrams for a letter series tractor. The main difference will be wiring up the gauges.

I run a 10ga white wire for the main battery charging wire, from the generator to the regulator to the ammeter to the hot post on the starter solenoid. Everything else is 12ga for simplicity.

Thanks Barnyard, where is the Bob M wiring diagram located... I've seen it before, don't recall where.

Also thanks to all for the replies.
 
Sounds like you have the mechanical aptitude and understanding to make your own.

If you make your own harness you will have the satisfaction and "warm fuzzy" of knowing you did it yourself.

I agree, you should be able to buy the material much cheaper than pre-made
 
I'm glad I went the "buy a harness" route for my Super C rather than doing my own.
 
I used a replacement harness on my 450. Much easier routing the wires and hooking them up using the existing tabs that hold the cable/harness. The wiring diagram for the M is misleading as the
450 has a key switch, a starter button, and a cig lighter. There is a separate harness for the lights & aux. socket.

Don't take Dr. Evil the wrong way. He has a lot of experience using and repairing these tractors.

Good luck with your project and enjoy a great tractor.
 
I rewired a 350 gas this summer making my own harness. Didn't need all that other wireing that comes with since this had a alt. on it.
 

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