More 39 pu wiring

[malpais]

Trying to wire my 39 pu. Lots of boxes under dash. Have parts from 6 38-39’s and one nearly new harness, but colors are bad and diagrams unclear. What are these items please. Seems like horn relay, some pieces have a resistor, only one has resister and fuse. Some of the boxes have points in them but no coils to operate??

Don’t know if photos are attached, so may have to try again!

[V8COOPMAN]

Originally Posted by malpais

Trying to wire my 39 pu. Lots of boxes under dash. Have parts from 6 38-39’s and one nearly new harness, but colors are bad and diagrams unclear. What are these items please. Seems like horn relay, some pieces have a resistor, only one has resister and fuse. Some of the boxes have points in them but no coils to operate??

Don’t know if photos are attached, so may have to try again!

malpais ....OK, first row, left to right.

You are correct! First pic is a horn relay.

2nd pic is what is left of a LIGHTS circuit breaker. These took the place of a fuse (modern technology), and as it cooled after tripping, would auto-reset.

3rd picture is a circuit breaker on left, and ignition resistor on the right.

4th picture obviously "smoked"! You can see the remnants of the fuse holder on right, as well as an ignition resistor on left that got way too hot.

Note that the fuse was only to protect the lighting circuit. DD

.

[malpais]

Thanks. Didn’t think of a thermal strip type breaker. Knew somethin’ had to make those points move!

Which was first - fuse or breaker? Guess breakers are newer. The “smoked” one actually still had a fuse in it. All confusing ‘cause my truck seems to have no mounting holes for the three items. Maybe 38s and 39 were different.

[JSeery]

Yes, 38s and 39s were different. Lot of changes going on over these years! And even through the model year. One big change in 39 was switch from 3 brush to 2 brush generators. The fuse/resistor panel was 38. 39 switched to the CB/resistor, but I have no idea when in the model year.

[malpais]

Thanks for the reply. I’ll have to look at dashes to see what year I got stuff of of. I’m sure my 38 big truck had fuse and resister.

At least one of the breaker boxes has two sets of “points” in it. Maybe two things protected?

Never let a project sit for 5 yrs!

[V8COOPMAN]

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Originally Posted by malpais

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At least one of the breaker boxes has two sets of “points” in it. Maybe two things protected?

I THINK in 1941, they went to a double pole breaker of sorts, pretty much splitting-up the lighting circuits, likely to lessen the current load on a single breaker.

[JSeery]

Basically headlights were on one CB and the rest of the lighting on the other one.

[malpais]

Got a booklet from rock auto that covers Ford 32-53 “Cars and light trucks”. NOT!!

But it does show the cars went to a single breaker in 41 and duel breakers in 42.

[JSeery]

The wiring diagrams show 40 as the first year for the CB. But, again, lot of changes in these years. I've seen 39s with a CB, but may will have been a later modification. Also, the wiring diagrams don't always match the modifications through the model year. The Green Book shows the CB/resistor panel as a dealer replacement part back to the earlier model years.

[drolston]

My stock "early model year" '41 coupe has two circuit breakers; one for headlights, other for other lights.