1954 Dodge M37 Restoration Project

[Blue Chips]

I haven't posted for a while (too many and boring reasons to mention here), but I'm finally getting back on my M37 restoration project again.

I've found that by breaking a project up into manageable sub-projects I can get a better feeling for progress made, not to mention getting some 'closure' once in a while.

I decided that my next 'sub-project' would be the instrument panel. Here's how it looked before working on it:

I decided to restore as much of the hardware as practical. Since the rust was just superficial, I bead blasted a number of parts in preparation for zinc electroplating. Here are a few parts ready for plating:

Some parts in the zinc plating bath:

Some parts after plating and passivation coating:

After plating, the instrument cluster lights were in excellent condition except for the wires and the ends of the rubber boots that seal the wire coming out of the socket. Rather than replace entire light assemblies, I replaced the wiring with the proper mil-spec wire, installed closed-cell EPDM foam seals (cemented on with Loctite 480), followed by heavy-wall heat-shrink tube. I made sure that the wire could still slide in and out of the lamp socket through the foam seal so that it would not affect the spring pressure of the contact against the base of the lamp.

I replaced the old light bulbs with LED lamps. However, these turned out to be too bright. More on that later.

 

[Blue Chips]

I decided to bite the bullet and replace all of the gauges in the instrument panel, due to a combination of some non-working gauges and cosmetic issues...and being a fussy old codger, of course.

The bezels of the new gauges came pre-painted green, but they didn't match the Marine Corps green that I'm using, so I prepped them for painting. I cleaned the bezels with mineral spirits (white spirit), used a circle cutter to cut masks from adhesive-backed stencil sheets, and masked everything but the bezels. Here's the new speedometer, ready to paint.

I bead blasted the instrument panel, primed it with self-etching primer, and painted it Marine Corps green.

While waiting for some instrument panel parts to arrive, I ordered and received another wiring harness, which I added to my 'pile o' harnesses.' All of the harnesses in the photo below are new except for two small headlight harnesses, which are still usable. I should be able to use all of the harnesses as-is, with only a couple of minor modifications for the new turn signal switch and flasher, and capping the ends of the blackout light wires at the stop and turn signal lights because of the interior mods I've done to those lights (as posted earlier).

I obtained a new 'spider' harness that supplies power to four of the instrument cluster gauges:

I also found a set of replacement quarter-turn studs and clip-on receptacles for mounting the instrument panel to the dashboard. The brownish color on the clips is a passivation coating, not rust.

I thought I'd do some work on the turn signals while waiting for a few items for the instrument panel. My M37 came with a Signal-Stat 600 turn signal switch, but I decided to switch to a Signal-Stat 900 turn signal switch, partly because it has a slide-out switch for a 4-way hazard flashing mode that doesn't require extra wiring. I did a couple of minor mods (not shown here) to alter the wire routing and to replace the original 12V incandescent pilot lamp with a 24V LED lamp.

This is the original relay-type turn signal flasher. As you can see, it's pretty complex and involves a fair number of external wiring connections.

I decided to eliminate the original turn signal flasher and replace it with a solid-state flasher to simplify the wiring and improve reliability.

 

[Blue Chips]

The two mounting studs of the new speedometer are metric (M5), so I had to tap the spider harness mounting stud/post to M5. It fits perfectly now.

The other new gauges arrived, and I painted the bezels Marine Corps green.

I've pretty much completed the instrument panel rebuild. Here are some before and after photos:

This is pretty close to how it looks to me in person when the shop lights are out and the instrument lights are on. They are probably a little brighter than necessary, but acceptable. I ended up using some LEDs that I already had on hand. I'll have to look through my old orders to see if I can find the model name/number for the LEDs.

 

[Bobupndown]

Fantastic attention to detail.

 

[Blue Chips]

Fantastic attention to detail.

Thanks!

I just received the solid-state flasher unit that I plan to use.

My cunning plan is to replace this:

With this:

I believe I have all of the wiring changes figured out, but I won't be ready to actually connect anything for a while, as the cab and dashboard will need restoration work before I can start installing wiring.