Beck TD, Part 22 - Gauging the Gas

In a recent post, I mentioned that I had the gas tank out in order to treat some surface rust, and also to replace the fuel level sender in the gas tank. In 1952, MG didn't want to waste a gauge on fuel level. Instead, there was a light that illuminated when the tank had about three gallons left. Of course, my 65-year-old sender was a mass of corrosion, and didn't work at all. The light in the dash didn't work either, and the wiring had been changed. A perfect trifecta of non-working-ness!

I ordered the sender, and it was back ordered. Still is, a couple of weeks later. I didn't want to wait, so I reinstalled the tank and got to work on lighting, as detailed in Part 20. However, in that post I didn't mention that having the tank in place without the sender installed really stank up the shop with gas fumes. I couldn't stand it. I decided to reinstall the bad sender. The only problem: no access.

I thought and measured, and realized that if I had a thick, straight screwdriver of a certain length, one that didn't flare out at all, I could install the old sender, and later install the new sender, without removing the tank again.  All of my motley collection of mostly inherited straight stubbies were too long and too wide, so I decided to make the right driver for the job:

It's the fancy brass one. I knurled a substantial piece of brass, drilled it an inch deep, and pressed in a straight-shanked hex bit intended for a drill-driver. Works perfectly! The right tool for the job is a joy forever, more or less. At least, it will become part of my permanent collection of tools.

Incidentally, the technique to make that screwdriver grew out of a project I did for the Make717 makerspace. I've been demonstrating lathe technique for the group at the Lancaster Science Factory and the Pequea Valley Planetarium, and having a lot of fun hanging out with my good friend Phil Oles (he demonstrates home-machined steam engines), and letting little kids (aged 9+) have a try at using the lathe under very controlled conditions. Here's an example of the Make717 Fancy Drivers.

With the sender problem solved (at least, if it ever arrives), I could check the wiring. When troubleshooting the wiring for the lighting project, I had made a 14-foot-long probe for my digital meter:

I used that to track down the right brown wire under the dash, and was ready for the lamp. That is one weird piece of design work. In 1952, there were no LEDs, and standard 12 volt lamps were hot enough to melt the early green plastic lens of the fuel warning light. The design solution was to wrap the lamp holder in resistance wire to drop the voltage to about 2 volts, and use a matching bulb. Only problem... resistance wire doesn't last 65 years. Mine was in multiple pieces. And that socket was a short circuit waiting to happen anyway - here's mine, with the resistance wiring already in the trashcan:

It seems to be a common modification to convert to LEDs, but instruction on how to accomplish it is scant. I'm gonna fix that, right now. First, I had to find a suitable LED setup, and this one is perfect. From Oznium.com, it is available in black or silver, and in multiple colors of LED:

I actually bought mine from Amazon, and at the time of this writing, this was the link for a pack of three at $22. Click the picture for the LED color and finish you want, and whether you want one or three:

https://www.amazon.com/gp/product/B01F2GTJ7Q  

When that quits working, I'll bet a search for "Oznium LED Indicators" will work.

Of course, the hole for the old indicator is much bigger. The easy solution is to use a 3/8" washer. If you spend some time polishing it (which I didn't) it would probably look pretty good:

But I like to make things, and I have the tools. And, just today I was gifted with a few pieces of 15/16" steel that was perfect for the job. I turned a shiny surface, drilled through with a letter "P" bit to match the threaded part of the LED, and then used the lathe to put an angled face on it.

Then, I used a 7/16" end mill to bore a pocket 0.080" deep for the LED:

Then I moved to my Logan lathe, which I had set up in the slow, powerful "back gear" to part them into bezels, 0.100" thick:

It turned out rather well. Here's the new LED mount, shown next to the stock red generator light:

Once I get the fuel sender, I'll wire it into the harness and have a working fuel gauge. For now, I just hooked it up to see how it looked. It's plenty bright - note the reflection on the spoke of the steering wheel:

The red generator light next to it is dead too, and it's sort of superfluous since Beck TD has an ammeter that tells me whether the generator is working or not. I bought a pack of red LEDs in the same Amazon order, and I'm going to repurpose that location as a red high beam headlight indicator. The switch to the right is the non-stock turn signal switch. I'm going to relocate it and add a green turn signal indicator in that location, so I can see when the turn signal is on. Right now, I keep leaving it on after the turn...

Continue on to Part 23...