Mechanic’s Tale: Special Tools

More Mechanic's Tales from Doug Flint  

Yesterday I was working on a 2001 Jeep Cherokee. We have already had several 80-degree-plus days so the owner noticed the air conditioning wasn't working. The refrigerant had all leaked out. Since it was a six-year-old vehicle I didn't expect to find any major problems – it had probably just lost a couple of ounces a year until there wasn't enough left to do anything. But in that job, the glaring aggravations of auto repair came to light.

Special tools.

When I get an air conditioning system that's low on refrigerant my procedure is as follows: Add enough refrigerant (usually a pound of recycled) to test the basic system integrity. Make sure the compressor turns on without any terrible noises, then make sure it actually cools and there are no leaks so large as to be audible. Then I check the one thing you can't check while you’re A/C service machine is hooked up, the Schrader valves. This is because the A/C service machine hooks to these valves. The service ports on an A/C system have valves just like the ones on your tires where you put air in. No high-technology testing device here. I just put soapy water in the well of the valve and look for bubbles indicating a leak—and sure enough, they were leaking.

So it should be a piece of cake. Two new Schrader valves, vacuum out the A/C system, put “virgin” refrigerant in with a little oil and leak detection dye, and presto. Except the tool I have for taking out Schrader valves, which is about a hundred years old, isn't quite deep enough to get one of the valves out. For no good reason the engineers have changed the design ever so subtly that the old tool that looks like it will work won't. None of my parts stores had anything that would work, so after losing two hours I cautiously, using my grinder, modified my tool to work. I've made a mental note to order the new tool next time the Snap-On Tool truck comes. A subtle, unnecessary change has rendered another reliable universal tool useless.

Fastening devices

My guess is that somewhere around 1965 every nut, bolt, and fastening device that would ever be needed to assemble a car had been invented and perfected: The six-point (hex) bolt. The twelve-point bolt in either fine or coarse thread in a variety of strengths and numbers that could cover virtually every application, including where spatial limitations prevented the use of a conventional wrench or socket. The good old Allen-head bolt (an internal six-point) such as the type that served my '79 Triumph Bonneville motorcycle and all the Ikea furniture I ever bought.

Unfortunately the inventing didn't stop there, but for good reason. Can you picture the scenario?

Chief of 500-man Fastening Devices department talking to head of company: "Sir, I believe we have invented every fastening device you will ever need."

Head of company: "Excellent, Perkins. You and all of your men are fired."

Not very likely. No, they kept right on inventing, each new device with a claimed benefit, which is usually more accurate or equal torquing. I should have taken the warning 26 years ago when I went to change the head gasket on my '73 Pinto requiring an odd internal twelve-point adapter that had a nasty habit of rounding off at about every 4th bolt, requiring a $12 expenditure each time.

Anyone who went to change a GM headlight in the Eighties discovered that the reliable old Phillips-head screw had been replaced by a strange device called a torx. Now there are torx bolts, and tamper-proof torx bolts so your old torx tools won't work. There are internal torx bolts and tamper-proof internal torx bolts and strange things called double Ds (no, not Double Ds!) in a variety of sizes. And all of them strip round and break and give us more problems than the old-style fasteners. GM brake calipers have internal torx bolts that destroy at least one tool every month or so. And in spite of the great variety of presses, adapters and special sockets that I have spent a fortune on to deal with such things, the ball joint always winds up being knocked out with an old socket and a big hammer and the oxygen sensor always requires that someone sacrifice a wrench to either cutting or heating and bending to get it out.

I imagine about ten years from now a clever engineer will invent a revolutionary fastening device that will accommodate all automotive, marine, and aerospace needs and require very few tools to service. Fantastic savings on all industrial production will be claimed as this device, available in only ten sizes, will eliminate the need for the thousands of fastening devices now currenty used. It will look remarkably like the old square-headed bolts of the 1920s and 30s, affectionately referred to as farmers' bolts or tractor bolts, which you used to buy at your local hardware store. When you had a local hardware store.

Doug Flint owns and operates Tune-Up Technology, a garage in Alexandria,Va.