Better Beaters - Building Cars and Daily Drivers

 Doing a little work on the '46 Plymouth. Part One.

Adding an extra electric circuit.

Finally! It's about time.

Hey, I've been quite busy lately.

Selling cars is no cakewalk. There is the process of prepping them for sale. With the Riviera it was replacing the water pump and belts. The Navigator required a complete new set of air springs. Then there are the oil changes and smog checks. Then driving them to be sure that they are running okay. Then the photo session and listing for sale. Then the hope that someone will want to buy them. I took the Riviera to several Cars and Coffees hoping that it would catch a potential buyer's eye. It didn't.

Well, now they're gone, so I have some extra space and some time to refocus my attention on the Plymouth. My plan was to take the car out of the garage and spend some time fixing a few things on it.

The first thing was to put the charger on the battery and bring it back up to snuff. I checked the standing voltage and it was 4.6 volts. That's kind of low, but the car had been sitting for a few months. I hooked the charger up and after an hour or so it indicated that the battery was fully charged. I checked the voltage and it read 6.0 volts. I left the charger on for some more time, figuring that the trickle charge function would give the battery a fuller charge.

I checked a couple of hours later and it read 5.4 volts. How could it read lower than after it had been charged earlier? 

So I put it on for some more time.

This time it read 4.6 volts again!

So I put it on for a little longer.

After an hour and a half the battery again read at 6.0, was the battery really fully charged? 

I switched the headlights on and a barely discernible orange glow colored the filaments. Hmmm, what is up with that? I don't know how old this battery is, I only know that it had been starting up the car fine until it was sitting for a few months.

The battery indicates six volts on the voltmeter, but it obviously doesn't have any power.

Then a light came on in my head. I remembered how the battery in my Daughter's car had given me headaches, a few years ago. 

I had chased electrical problems to the Smart Fuse box, which I replaced with no improvement. That battery read at 12 volts, so it couldn't be the problem, could it? Finally in frustration, I took it to an O'Reilly's where they put in on a stress tester. The battery was very low on cranking amps. It was toast. It didn't have enough power to keep everything running correctly. A new battery for a couple of hundred bucks solved that problem.

I guess that it was time for a new battery for the Plymouth.

I usually buy my batteries at the local NAPA dealer, Winchester Auto Parts. I figured that I would have to order it, then pick it up later. I didn't expect them to have a six volt battery in stock. But, I was surprised.

A beautiful new battery for a 79 year old car.

They had a whole selection of six volt batteries in stock. It turns out that a lot of folks in my part of town have old collector cars that need six volt batteries. Not to mention riding lawn mowers and garden tractors and I guess even snowmobiles or whatever. 

With the old battery out from under the hood, the date sticker was now visible. It was dated to 6/2020, five years is pretty good for battery life. The counterman did a load test on the battery, it only had a couple of amps left from the original cranking spec. 

They had the exact battery that I needed, and to top it off, it was much cheaper than the last battery that I had bought for my '06 Mustang. The shop even gave me a discount, which brought the total to less than 125.00! It is worth doing business with a local store!

I know I should have scrubbed it down with baking soda,
but I was in a hurry. Note the protruding bolt head.

When I pulled the battery out I found an old piece of cardboard underneath it, and some rust on the battery tray. Since I had it out, I figured I should spruce that up a bit. There was a bolt head that was sticking up a bit from the tray surface. I suppose that's what the piece of cardboard was supposed to address. 

I scrubbed it down with a wire brush, then dug through my old paint can stash for some type of black paint. I found some black brake caliper paint that my Son had left behind. I shook the can and took a test spritz and it was still good. Did you know that it is better to store paint spray cans on their sides? 

Things rings provide a level support for the battery.
 The caliper paint is shiny, and adhered to the metal pretty good.

I cut some rubber rings from a section of heater hose to support the bottom of the battery, and made a mat out of some closed cell foam.

I used what I had on hand. I'll see if the closed cell foam will work out over time.
If I had some rubber sheet I would have used that.

I installed the battery, snugged everything up  and now I should be good to go for the next four years.

Now that I had a steady source of voltage, I wanted to address a problem that arose after I installed my CHMSL. I had used the brightest six volt bulbs that I could find. I wanted traffic behind to know that I was stopping!

The first problem was that the CMSL, once installed, was never as bright as when I had tested it using the battery directly. 

When I had posted my progress on the AACA forum, a couple of members responded that the change I made was sending a lot more amps down the wires than was originally planned for. They told me that there was a good chance that I would burn out the stop lamp switch. Another told me that I might even burn up the wires running to the lights, or even the car! 

What were they talking about?

I had replaced the bulb in the original brake light with an 1129 bulb. Then I'd added two 1129 bulbs in my CHMSL assembly. All were running on the original brake light circuit. My car had been rewired when it was restored back in the 1980's. Truthfully, the wiring harness did not look like a real good job, the wire used looked a little thin, more suitable for a twelve volt system than a six volt system. However the car had survived over 30 years of use without burning up the wiring. 

Remember, that a six volt system uses half the voltage of a twelve volt system but everything uses twice as many amps. Therefore the wires are much thicker than in a more modern twelve volt modern car. That is why it is acceptable to convert an older car's electrics to 12 volts, the wires have no problem with the lower amperage used. 

For example, the turn signal/ tail lamps are 1158 bulbs. Amperage is 0.75 for the running light, and 2.63 amps for the turn signals. My 1129 stop light bulbs each pulled 2.63 amps each, for a total of 7.89 amps for the three lamps.

I really wasn't too worried about all that at the time. The bulbs gave a much brighter stop light, even if it wasn't as bright as when I tested it directly from the battery. This indicated that there was too much resistance in the harness to provide proper functioning of the bulbs. Resistance in a wire produces heat, that's how your toaster works!

One day I had the car out running errands that took me down the busy Capitol Expressway during rush hour traffic. Lots of stop and go driving and sitting with my foot on the brake pedal at stop signals. The car was running fine, and I'd developed a lot of confidence in the brakes. They stopped the car really well. I wasn't that concerned that the emergency brake wasn't working when I bought the car. I was only a few miles away from home when I came to a stop for traffic, and my foot went almost to the floor when I stepped on the brake pedal. 

I pumped the brakes and got a little resistance back. I proceeded through the intersection on the green signal and immediately pulled to the curb. I looked under the car expecting to see brake fluid dripping from the master cylinder or from the wheel cylinders. But there weren't any leaks visible. What happened?

I waited for a few minutes and the brakes returned. I carefully drove the car home and the brakes seemed to be working normally. 

I hypothesized that the overworked stop lamp switch had heated up enough to possibly boil the brake fluid. 

Now that I had a new battery I devised a strategy to test that hypothesis.