Permanent Headlamp Wire Modification

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10+ Years
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Zip Code: 44134
Tractors Owned: 1949 & 1951 Farmall Cubs

Several Snapper Garden Tractors
Circle of Safety: Y
Location: Southern Suburbs of Cleveland, Ohio

Permanent Headlamp Wire Modification

Postby lazyuniondriver » Fri Nov 09, 2012 1:16 am

Some folks, especially those still using their tractors for chores will sometimes prefer to deviate from correct to practical for the simplification of future repair work, hood removal for example.

I use this modification when the headlight harness has been cut for hood removal on earlier screw back lamped tractors.

If your tractor has had the headlight wire(s) cut instead of disconnected from the individual lamp assemblies, and you are not concerned about period correctness, this may work for you as well.

This method simply connects the left light to the right light where it mates with the feed at the right light.

The right light essentially becomes a junction block, eliminating a need for a splice between lights under the hood.

The feed wire is then fitted with a bullet style coupler at the termination point of the original harness which will serve as the plug for future hood removal.

The underhood wires are protected from chafing by the fan, belts, and pulleys by running in wire guides under the hood.

I utilize the JB tube welder to attach a 9" long piece of 1/2" thinwall to the underside of the hood to serve as the cross hood wire guide.

Form this peice by slightly bending or curving it to conform to the slightly rounded contour of the hood. Use the topside of the hood as a pattern.

The conduit when attached runs parallel with the radiator, 1 1/2" behind the radiator neck punch out.
Cross Hood Wire Guide
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If suitable conduit material is not available, dabs of Bondo or tube weld will work to tack the cross hood wire up out of the way. I would run it in wire loom if I utilized this method, bonding the loom to the hood with the wire inside it.

Whichever method is used, clean the underside of the hood to bare metal for satisfactory adhesion.

Cut a second piece of thinwall 4" long and tube weld it to the inside of the lowest rib on the right side of the hood, (generator side) as pictured.
Side Wire Guide
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Next, cut a 36" length of suitable wire that will run from light to light. I use 12 awg stranded wire. Strip 3/8" insulation from each end.

Prepare a blue "eye" terminal by removing the blue plastic insulator from the terminal. Cut a 6" length of heat shrink tubing and slide it over the wire before crimping the terminal "eye" to the wire end.
Slide the heat shrink tube up to the terminal eye and heat.
Terminal Ends
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( If professional grade crimpers such as Thomas & Betts brand are not available, I would highly suggest soldering the connection instead of relying on an inferior crimp that may later fail. If the crimpers you use have ever failed to crimp a solderless terminal, solder the terminal instead. )
Professional Grade T&B Crimpers
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Prepare a second 16" long wire that will serve as the feed. Strip 3/8" insulation off both ends. (If the original harness terminates near the voltage regulator, 16" is perfect. If you need to splice in farther back towards the dash, add wire length as needed).

Prepare a yellow "eye" connector by removing the yellow plastic insulator from the terminal. Cut a 6" length of heat shrink tubing and slide it over the ends of both the cross hood wire and the feed.

Crimp the larger "eye" connector onto both wires, slide the heat shrink tubing up to the terminal eye and heat.

Cut 2 more short pieces of heat shrink tubing for the feed. Prepare the stub of wire on the tractor from the light switch and crimp the female half of the bullet connector onto it, sealing the deal with a piece of heat shrink tubing.
Bullet Connector Harness Plug
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Crimp the male end of the bullet terminal to the lamp end of the feed wire originating at the right headlight and shrink the tubing around that connection as well.

I prefer to leave the plastic insulation on the bullet connector ends to provide rigidity for the purpose of future handling. The heat shrink can cover all the plastic if you like.

Remember if you are working with the hood upside down, the headlight with both wire connections is on the same side as the generator oiling holes punched in the hood.

Insert the single end of the cross hood wire into the long wire guide from the right side of the hood and route it out the left grommet hole connecting it to the left headlamp. Route the the double ended terminal out the right grommet hole and connect it to the right lamp.

Slide the feed wire into the short side guide and you are done.

Install your hood and simply plug in the harness at the bullet connector.

This modification will last another 60 plus years thrilling future disassemblers with the convenience of a simple headlight disconnection as well as offering protection of the lamp wires from moving parts.
Dual Wires Hidden in Heat Shrink Tubing
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Materials List:
13 inches 1/2" thinwall conduit.

52" 12 awg stranded insulated wire.

One blue 16/14 gauge and one yellow 12/10 gauge crimp on "eye" ring connector.

One blue 16/14 gauge male/female bullet connector.

16" heat shrink tubing. (I use black).

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