Tech Tips: Summer 2000

Driving Light Relay

When I installed a driving light on my MC TC, I powered it through a relay. This allowed me to apply full battery voltage to the light without subjecting my driving light switch to the full lamp current. It also allowed me to tie the driving light into my high beam switch without increasing the load on that switch appreciably. Now when a car approaches and I dip my headlamps, it automatically turns off my driving light as well to prevent dazzle of oncoming traffic.

Steve Tom

Keep Your Car Cool or Warm

After having been subjected to the usual interior conditions of British cars with their tops up in hot weather, we looked for a way to keep the interior heat to a minimum. We decided to try cutting a piece of insulation (Moss 409-015, heatshield material) to fit between the top material and the support bows. We measured the size we needed and cut it to fit. We started with a piece that was a little too large and then trimmed it a little each time, fitting it until it was just right. Since we wanted it to look like it was part of the car, we covered it with a piece of black shade cloth (a heavy porous vinyl material used for gardening) that is available from Home Depot or any good gardening supply store. We cut and taped it to the insulation with duct tape and installed the completed piece into the car. Once installed, it was not noticeable, even when looking into the car.

When we wanted to drive with the top down, we just rolled up the insulation into a small roll and stored it in the car. Reinstallation took only a few minutes when we put the top back up. Not only did the insulation keep the car cool during the warmest part of our drive by reducing the solar heat gain through the black top, it also served to deaden the outside road noise. Our tour was much more comfortable than during previous trips. The insulation pad should also help keep your car warmer during the winter by keeping the heat in.

Bob and Barbara Humphreys

San Diego, CA

Get a Grip

Recently, the rubber grip on my TR6 steering wheel broke free from the underlying metal rim. I asked many knowledgeable people, but none had an easy and reliable fix. I put some of my radio-controlled model building expertise to use for this problem.

You can obtain a small bottle of Super Thin cyanoacrylate glue from a local hobby store. Use a long, large diameter 18-guage needle to pull the glue out of the bottle. Then remove the 18-gauge needle and attach a smaller 22-gauge needle. Then insert the needle from the inner-rear of the wheel so any puncture marks will not be visible. Insert the needle until you strike the metal core of the rim. Inject about l-cc every few inches along the rim where the rubber is loose. You must do this fairly quickly as the glue sets up fast.

Set the steering wheel aside for an hour to be sure that the glue is completely set. It is supposed to set in a few seconds, but inside the rim, setting might take longer. So far this method has worked beautifully for my steering wheel, and it seems as strong as the original glue.

Anthony Rhodes

Horsham, PA

Keep the Dash In

Recently my buddy and I needed to replace the heater fan on his 1974 Triumph TR6. Every manual I have states that the dash panel assembly has to be taken out. We were really dreading disconnecting all the dash gauge attachments and lamp connections. To our delight, we found a way to avoid extracting the dash.

Of course, we still had to drain the heater core, take out the radio, take out the cubby box, disconnect the heater hoses and defroster hoses, loosen up the choke and heater cables and drop the heater unit assembly.

Here is the trick to avoiding dash removal. Once the above-mentioned items are disconnected, the heater unit assembly, which houses the heater fan, is ready to be unbolted and pulled out. Most nuts securing the heater assembly are reasonably accessible except for one almost directly on top of the healer unit.

The trick is to take out the cigarette ashtray. There is then just enough space to insert a 7/16” offset style ratcheting box-end wrench through the ashtray hole. In this way, the final nut holding the heater assembly can be unthreaded and the assembly dropped out. We estimated this shortcut saved us about two hours of dash disassembly and reassembly work.

Dave Wood

Gainesville, FL

The Hose Knows

Here is a problem that drove me crazy for a year or more. My wife has a 1976 MG Midget 1500 that would run fine, then all of a sudden it would shut off as if it were out of gas. Every time I checked, there would still be gas in the lank. I tried everything I could think of, flushing out the gas tank, replacing the mechanical fuel pump with a new one and also an electric fuel pump was installed.

New rubber fuel lines replaced the old dried-out ones, I thought. While I was checking the fuel line to the mechanical pump again, I felt something give. It was the metal line that ran behind the engine to the other side of the car and disappeared underneath the car, back toward the gas tank. Wiggling the metal line, I could tell that it wasn’t metal the whole way back. In fact, there was a short section of 20-year-old brittle rubber hose about seven inches long that had missed being replaced. It ran around the frame from the steel line for the older 1275cc engine to the steel line for 1500cc engines mechanical fuel pump.

After the line was replaced, I examined the old one and it had a split at one end at the clamp. It hasn’t run out of gas with fuel in the tank since. Now we feel much better about taking the MG on longer trips.

Chris Lutz

York Haven, PA

Losing Your Bearings

The MG TC uses ball bearings in the front wheels, which mean the inner race and outer race line up vertically. This bearing is held in place by a nut and a slightly dished washer. The curve of the washer ensures it will press against the inner race and will not touch the outer race.

Since the inner race is stationary on the stub axle and the outer race turns with the wheel, it’s good to have a little clearance between the washer and the outer race. None of my MG manuals even mention the fact that this washer is dished, let alone tells you which way to install it.

Several TC experts insisted this washer could go on either way, and even said that installing with the dish facing the other way would add a little spring to the washer and keep pressure on the bearing, even if it is necessary to hack the nut off a bit to line up the hole for the cotter pin. However, this is a bad idea.

When doing this, the washer touched the outer hearing race. The washer will press against the outer race of the bearing. The washer, rubbing against the outer bearing race, can get so hot that it could weld itself to the race. Once the washer starts spinning with the bearing, it can rub against the nut hard enough to shear off the cotter pin and tighten the nut. As it tightens, it can pull hard enough on the threaded end of the stub axle to break it off.

Installing this washer backwards may not break the stub axle every time. A more common result is undue wear on the washer until it no longer presses against the bearing. This is still not a good thing to have happen, as it will fill your bearing with metal shavings.

Steve Tom