It’s easy to remember the triumphs in my career as a mechanic. Like the time I smelled something odd that led to an inspection that prevented a catastrophic engine failure. Or the midnight service call about an engine that was “trumpeting like an elephant” when it was put on more than ¾ load. That unique symptom turned out to be a loose hose clamp on an air-to-air intercooler that allowed pressurized air to escape and vibrate the end of the rubber hose and create the trumpet-like sound.
However, it is certainly much more difficult to remember my goofs, screw-ups, and blatant mistakes because my sense of pride tends to store those within the dark corners of my mind.
While those mistakes are good for a laugh now (though still not from myself ), each of those mistakes did teach me a valuable lesson.
The following are some examples of lessons I learned the hard way:
- Puffs of smoke are bad when working on electrical systems. As a grizzled mentor explained to me, “Them electrical things, the wires and stuff, they don’t work so good after you let the smoke out of ‘em.”
- If you use compressed air to push out the ram when disassembling a hydraulic cylinder, don’t have your service truck parked broadside, down-range from that cylinder.
- Always remove the retaining pin from the flywheel after installing a diesel injection pump before you try to start the engine. That’s the pin that maintains engine timing while the pump is removed. Don’t even ask what happens if you try to start the engine while that pin is in place.• Never use anything but air tool oil to lubricate air tools. I thought I’d save a few bucks as a young mechanic by using engine oil or whatever leftover oil was on my benchtop. Expensive mistake.
- Always disconnect the negative battery connection when installing any electrical component, even if it’s just an alternator. Fireworks are great on the 4th of July, but bad when working on electrical things.
- Never test-run a conveyor, shaker pan, or processing machine with close internal clearances without inventorying all the tools you used during repairs. Especially 32-ounce ball peen hammers.
- Never weld while standing in a puddle of water. It can let the smoke out of you.
