Imperial Journey

With the paint finally finished the next step was to reinstall all of the trim on the car – all 873 pieces of it. There are three types of trim pieces on this car – steel (mainly the bumpers), cast pot metal, and stainless steel. Each requires different treatment.

The bumpers were straightforward – just bolt them into place with 1/2″ bolts. The only real challenged was wrestling these three ton parts into place long enough to get the bolts started. By myself… OK, maybe they are only 50-60 pounds, but that is still a lot heavier than it used to be!

The cast metal parts use threaded studs that screw into threaded bosses on the part. In the past I’ve used the double nut approach – screw two nuts onto the stud, tighten them against each other, and use this to screw or unscrew the stud into place. This works well, but it is time consuming and tedious.

Looking through the Bolt Depot website I happened to notice set screws. Just a minute – these are just like threaded studs, except that them come in various lengths and have a hex drive! They are also available in stainless steel at a reasonable price. OK, I need a couple of bags of these! They worked great; much easier to screw into the parts than threaded studs. The parts installed just like with the original studs. They should, since the only difference between the threaded studs and the set screws is the hex drive.

All in all the only real challenge with the cast metal parts was the cost of having them re-chromed.

The stainless steel side molding trim had been giving me heartburn for the last couple of years. These parts are formed sheet metal and are held in place with plastic clips. The 60 year old plastic clips break when you breathe on them – I broke practically all of them removing the trim from the car. And, of course, they aren’t available. Modern cars either don’t have trim like this, glue the trim in place, or use different styles of retainer clips.

Around two in the morning inspiration struck. A couple of weeks later I actually remembered it during the day: what about making a square tab out of sheet metal to fit in the mounting grooves in the trim pieces? Time to head out to the workshop and make some test pieces! Measurements suggested that 3/4″ would work. A piece of scrap sheet metal was cut to size and proved to fit perfectly.

This left the issue of attaching it to the car. Instead of a snap-fit plastic part, what about welding a bolt to the tab and securing it with a nut inside the car? Nope, wouldn’t work. The nut is too thick. Just a minute – what about a piece of threaded stud? Weld a stud to the tab, slip the tab into the trim piece, position it on the car, and screw on a nut from the inside. Well, would you look at that – works perfectly!

Counting mounting holes in the car told me that I needed to make about 50 of these mounting tabs, each exactly 3/4″ wide. With rounded corners. The threaded studs I had were too long, so I had to cut them in half and weld them exactly in the right place. Not looking forward to this!

Having a solution was good. Implementing the solution would be annoying. Just a minute – this is the kind of thing SendCutSend does! Hop onto the CAD system and design a 3/4″ tab. With rounded corners. And a hole in the center to locate the threaded stud. Hmmm, for this part the pricing is the same for mild steel and stainless steel… OK, stainless it is!

And then another thought struck – didn’t set screws come in various lengths? Yes, yes they did! Set screws were available in the 1/2″ length I needed. And stainless steel isn’t much more expensive than mild steel. OK, these mounting tabs are never going to rust.

I needed some way to hold the tab and set screw in place while welding them. Something that would hold the set screw perpendicular to the tab. Ideally something that would position the end of the set screw even with the back of the tab.

What about taking one of the chunks of 5/8″ steel plate left over from an earlier project and drilling a hole in it? Drill the hole just deep enough that the set screw will stick out just enough to locate a tab when you drop it over the screw. This locates and squares everything and the steel plate won’t be affected by welding heat.

So that is exactly what I did – mill one surface of the plate flat, drill a hole the proper depth, and start making trim retainer tabs!

Top right: tab ready to weld to set screw. Top Left: Tab welded to set screw. Bottom Left: weld on tab ground flat. Bottom Right: Finished trim retainer tab. Note the ground clamp on the jig block – welding works much better when you remember to do this!

Being paranoid, I took the first half dozen retainer tabs and used them to test mount several different pieces of trim. They all worked so I went ahead and made the entire batch. There were several places where the trim originally used threaded studs and the 1/2″ studs I was using were too short. For these I made a set of retainer tabs with 1″ threaded studs.

Everything went together reasonably well. There were a few places where I couldn’t reach to get the nuts on, but the trim pieces were well secured with the ones I could reach.

The trim around the rear window was also stainless steel. It was wider than the side molding trim, and already used metal tabs and threaded studs. These tabs were wider and the studs were longer – 1-1/4″ vs. 1/2″ since they needed to go through the heavy rubber molding that secures the rear window. These studs were also smaller – 8-32 vs. the 10-24 studs used in the side molding. In addition, the studs were offset from the center of the tab.

Unfortunately 8-32 set screws don’t come in 1-1/4″ length. But bolts do… Fine, order a bag of 1-1/4″ bolts and cut the heads off!

Most of the old tabs had rusted out. Fortunately there were enough good ones that I could take measurements. Hop back onto the CAD system, design these tabs, and include them in the same SendCutSend order as the side molding tabs.

The welding fixture worked really well for the side molding tabs, so it was modified for the rear window tabs. In addition to needing a smaller hole it needed some way to control the length of stud sticking up from the top of the block. Four screws to a great job of providing this adjustment.

A few minutes of adjustment and the new trim tabs were welded up and ready to go.

While the stainless steel trim itself was in good shape, it had 60 years of exposure to the elements. Metal polish on a felt pad in a die grinder brought it back to a factory fresh luster.

All of the trim is back on the car and looking good. I think I’m ready for the first Cruise Night of the year!

Previous electrical: Electrical 15: Factory Wiring Diagrams.

With the beautifully chromed headlight buckets ready to install it is time to complete the job of upgrading headlight wiring. You may recall from a previous post that I left the original factory wiring in the headlights themselves, waiting for the chrome plating to be done.

This picture shows the freshly chromed headlight buckets, the crossmember that connects the two buckets on each side, the mounting hardware for the headlights that goes inside the buckets, and the original factory wiring. The wiring goes up the base of the inner bucket and then through the crossmember to the outer bucket.

The original harness had two inline connectors. It also had a single 16ga wire for the low beam, a single 16ga wire for both hi beams, and a single 16ga ground wire. Between long runs of thin wire, multiple connectors, and 60 years of corrosion there was noticeable voltage drop to the headlights.

The new harness has a single connector, which is now a waterproof WeatherPack connector. It has a dedicated 12ga wire for the lo beam, two 12ga wires for the two hi beam headlights, and a 12ga ground wire which directly connects to the battery. As a reminder, power for the headlights now comes directly from the battery going through relays. Wire length has been reduced from 8′-12′ for the factory wiring to about 3′ with the new wiring, further reducing voltage drop.

All connections are sealed with marine heatshrink tubing with glue. Wire harness braid is used for both appearance and protection from chafing. Also note that the wires are labeled – this continues to save me from mistakes!

The actual socket that the headlight bulb plugs into is now a high temperature ceramic socket. The factory headlights were 35 watt while new headlights are 55, 65, or even 100 watts. With new bulbs the headlight buckets might trap enough heat to melt normal plastic sockets. While I probably won’t run 100 watt bulbs I do plan to upgrade to 65 watt bulbs.

Since I knew exactly how to build the new headlight harness I only had to rework it four times. And the second harness went even faster!

With the headlight buckets attached to each other through the crossmember the headlight mounting hardware is installed in each bucket. The headlight bulbs are plugged into the new ceramic sockets, positioned in the mounting hardware, and secured with the retainer ring.

Chrome trim rings (not shown) are installed on the front of each headlight bucket and the headlights are finally ready to mount on the car! This was a simple job, so this 15 minute task only took me two hours.

The only thing left to do was illuminate the workshop with now high powered headlights! Which I proceeded to do with lo beam and no high beam. Krud.

I quickly determined that I had swapped the lo beam and ground wires on the connector. Fortunately I was able to remove these two pins (thanks to having the foresight to buy a WeatherPack de-pinning tool…) and move them to the correct locations. NOW I had bright lo beams and hi beams! The second pair of headlights worked the first time.

For now I’m still using the original sealed beam halogen headlight bulbs. These will be upgraded to modern H1/H4 bulbs when finances allow. Or when I start driving at night, whichever comes first.

Previous Electrical article: Electrical 14: MeterMatch

While looking over the electrical posts I realized that I haven’t mentioned one of the most important resources for working on wiring – the wiring diagrams contained in the factory service manual. These are absolutely vital to working on the electrical system!

Intimidating at first glance, a wiring diagram is actually your roadmap to success. They provide a complete picture of every wire in the car from battery to final ground, including all connections, switches, junctions, and plugs.

Consider this wiring diagram for the engine bay of a 1963 Imperial:

This diagram shows everything from the headlights on the front of the car to the bulkhead connector that goes through the firewall into the passenger cabin. It shows all the wires and where they are connected. Each circuit is labeled, such as A-1, H-3, or L-9C.

The chart on the left side of the diagram lists each circuit, the wire size, and wire color. Looking at the bottom right corner of the wiring diagram we can tell that circuit L-9C is a 16ga white wire that goes to the left most headlight. Tracing this across the diagram we can tell that L-9C goes to a 3-way connector, where is is connected to L-9E. L9E then joins with L-9D and L9. L-9D goes to the right side headlights and L-9 is grounded at the voltage regulator ground point. All of the L-9 wires are 16ga white wires. OK, L-9 is the headlight ground.

Right above L-9E is L-4D. Here is where we can apply some outside knowledge. We know that the outermost right and left headlights are combination Hi beam and Lo beam headlights, while the inner two headlights are Hi beam only. The wire that goes to all four headlights is Hi beam and the wire that only goes to two headlights is the Lo beam. Careful examination shows that L-3 goes to all four headlights, so it is the Hi beam. L-4 is the Lo beam.

Based on this we know that circuit L-4 is a black 16ga wire for Lo beam headlights and L-9 is a red 16ga wire for Hi beam headlight. Tracing the Lo beam wire, L-4D connects to L-4C which connects to L-4B which joins with L-4. L-4 then goes to Pin 1 on the large bulkhead connector on the firewall. If we go to the cabin wiring diagram we will discover that this wire goes to the Hi/Lo switch, the headlight switch, and ultimately a power source.

The same approach works for the parking light and turn signal. Again, we have background knowledge: the bulb for this grounds through the bulb base, directly into the socket and ultimately the car body, so all wires going into the socket are power. Parking lights are common, and will have a common power wire. Left and right turn signals are independent, and will have separate wires. Circuit L-6 is common to both sides, so it is the parking light. Looking at the left side of the car, L-6A is an 18ga yellow wire that joins to L-6A and L-6. L-6 goes to pin 6 on the large bulkhead connector. Inside the car it connects to the headlight switch.

This means that D-6, an 18ga light green wire that goes to pin 8 on the large bulkhead connector is the left turn signal. Circuit D-5, an 18ga tan wire going to pin 5 on the large bulkhead connector, is the right turn signal.

Because I’m easily confused I clearly label both ends of each wire when I’m working on a wiring harness with both the circuit number and the function – for example, “L-4D Left Headlight Lo Beam” or “L-3C Left Inner Headlight Hi Beam”. This makes life much simpler the next time I’m working on the electrical system – both for the function of the circuit as well as the circuit number for tracing across the wiring diagram.

This wiring diagram is actually fairly simple – others get much more complex. I find it useful to copy or print out wiring diagrams and trace circuits I need to follow with a colored highlighter pen. This makes it “easier” to follow a circuit end to end (or middle to middle), as well as keep track of multiple circuits. You don’t want to do this in the actual factory service manual since the page will become unreadable after tracing a few circuits. It is also easier to take one or two sheets of paper into the car while you are working on it than to drag the large factory service manual around. As well as making it easier to take notes while you are working.

With a set of wiring diagrams, a multimeter, and some patience and persistence you can tame the dragon of electrical wiring!

At least on old cars – modern cars use communications networks. These networks start with CANbus (Car Area Network bus) and are migrating to Automotive Ethernet. Yes, a variation of the same networking protocol used for computers! I stay far away from the new cars; these old cars are enough of a challenge.