Sometimes even when you know what you're doing, you still mess up. These mechanics had some very bad, no-good days when they made the worst mistakes of their careers. Sometimes is a loose something or other, sometimes it may be a leak, whatever it is, it's not good and these folks had to deal with it firsthand.
Content has been edited for clarity.
"I took an immaculate ‘97 Accord that showed serious ownership pride and created, because of my error, a total loss of $10k inside my shop without anything else being damaged. It was a simple job: brake pad change and strut replacement on all four corners. I used two post lifts in my shop. I drove the vehicle between the two posts. Each post had two arms that reached out under the vehicle and lift it from the frame mounts. This is a very popular, simple lift used in most shops. I used a muffler stand in assisting with the installation of the struts. Muffler stands are about five feet tall that when turned will lift an additional two to three feet. These stands are used by muffler shops to mock up and hold the new exhaust system in place under the vehicle so it can be welded and attached to the frame. I used the jack to put upward pressure on the lower control arms to help replace the new struts.
Mid-afternoon, I had accomplished nothing on this job due to customers and phone calls and needed to get the job finished ASAP. I let phone calls go to voice mail and put myself into overdrive. Once the job was completed, I removed my tools and parts from under the vehicle and slid the muffler jack out from under the left rear tire toward the rear of the car. In my haste to finish, I never once double-checked myself, as I trusted my supreme mastery of the task. (This act of itself is a prime example of someone smoking his own crack.)
So, as I stood next to the driver’s door, lowering the vehicle on the lift, staring out the front of the open bay door deciding what I wanted for dinner, I didn’t have a clue that the left rear corner of the car was not dropping as the rest of the car was coming down. In the end, one inch was all I needed. I failed to confirm the muffler jack I slid toward the rear of the car had cleared the bumper cover. That rear corner was still held up by the jack!
My peripheral vision noticed the driver’s door pitched forward. In a panic, I released the lift‘s switch and nervously watched the car teeter precariously...for about half a second. Then the car shuddered and took a nosedive. The front right corner hit first and the car bounced between the lift posts like a pachinko ball.
'Oh Fudge!' I said. (Okay, maybe not those exact words…) The bumper cracked, the fender bent. Creases were in the doorstop to the bottom. The C pillar looked like a washboard. I thought I was going to hurl. Then my reality sank in, and I truly wished this was a normal customer, not my mom. That evening I had to make one of the worst phone calls ever.
'Uh, I finished your car…but you’re not able to drive it home,' I said.
The best decision I ever made was having shop insurance, which paid handsomely due to the car’s pristine condition, blessedly allowing a large upgrade in the new vehicle she now needed to replace. I’m equally blessed this subject has not since been broached."
"As a young, 19-year-old backyard mechanic, I thought it would be a good idea to change the manual gearbox oil on my ’76 Audi Fox before embarking on a multi-leg road trip with a buddy to Florida, and later on to Arizona.
The oil filler hole was on the top of the 90-degree/inline transmission, and fairly difficult to see and harder still to get a filler tube into. Nevertheless, I drained the old oil, and snaked a fluid filler tube down around the back of the engine into what I assumed was the filler hole, and I slowly squeezed a quart or so (whatever the specification was) through the tube. After adding the required amount, I noticed a small puddle of fresh oil under the car. Since there was no simple way to actually check the gear oil level, I just assumed I overfilled it a bit, and that some excess had spilled out. I then re-plugged the filler hole and went on my merry way.
I’m sure where you can see where this is going…
Shortly after, my friend and I drove south from New Hampshire, through southern New England, through NY and the mid-Atlantic states, and all the way to northern Florida, when I started to hear an odd whining sound that ceased only when I pushed in the clutch. I realized almost immediately that there was something wrong with the gearbox.
While staying in Florida, I took the car to a transmission shop, where they had quite a chuckle at my expense. The technician called me back to the lift and showed me how the fresh, but tragically-misguided gear oil had puddled in a matrix of pockets and recesses on the top of the gearbox and subframe. He then shined a light into the drain hole and showed me how the bone-dry gears had turned blue from excessive heat and wear over the 1000 or so miles I drove it with no oil in the gearbox, whatsoever!
By an extreme stroke of luck, the shop was able to source another Audi Fox or VW Dasher gearbox and install it within a few days. Price at the time? About $450! Certainly that price would be tenfold on a modern Audi today."
"The biggest mistake I ever made as a mechanic was letting someone else handle something important and not confirming everything was done correctly before driving. My first vehicle was a 1967 Ford F-100. It was used for farm work and you could tell just by looking at it.
The truck had sat unused on my aunt’s ranch for over a decade since my uncle had passed away. My aunt offered to sell it to me for $1 right after I had gotten my license and my dad offered to help make the needed repairs. All I had to do was chip in for parts, watch, listen, ask questions, and be a second pair of hands when needed. A pretty sweet deal for a 17-year-old if you ask me.
My dad and I spent the summer picking away at the repairs and had it running well enough to use by the time school got back in session. The only things left on the to-do list were a new windshield and a brake cylinder on the front driver’s wheel. My dad had made the appointment to get the windshield installed for a Saturday morning. He decided he would go ahead and take care of the brake cylinder while I was at school on Friday so we didn’t have to worry about tackling it the next day.
I got home from school just as my dad was finishing up with the cylinder and bleeding the brakes. He was surprised to see me.
Dad said, 'What are you doing here? What time is it?'
I replied, '3:30.'
Dad said, 'Dang it. I know I got a late start, but I didn’t think it was that late. I have to go pick up your bother in 10 minutes. I guess I better get this done.'
I asked, 'Do you want any help? I can help with the brakes and put the wheel back on while you run.'
Dad replied, 'That’s OK. I got it. You go work on your homework.'
I went on in and didn’t think much of it. My dad was home about an hour later with my brother. We had dinner and called it an early night to get ready for the drive the next morning.
The morning came and we started making our way, me in the truck and my dad leading the way in his van (he knew where to go). My dad was ahead of me by a couple of hundred feet on the interstate, both of us pushing 80/85 miles per hour. We were about 20 miles down the road.
Suddenly I was looking at the road at a completely different angle and I heard a horrific grinding noise coming from the front driver’s wheel. I checked my mirrors and see my wheel bounce a few times on the interstate; it eventually rolled safely to the side of the road. After several hundred feet of grinding, I came to a stop. I hopped out and saw the bottom of the brake drum was now flat, with at least ¼ inch of the metal gone. It took 15 minutes for my dad to notice I was no longer behind him, get turned around, and find me by the side of the road. Apparently, he had forgotten to tighten the lug nuts and everything went downhill from there.
Instead of getting the windshield replaced, we wound up spending the day getting ahold of new brake parts, lugs, and lug nuts and making repairs on the side of the road.
Had I taken just a couple of moments to inspect the wheel after he finished, I probably would have noticed that the lug nuts were not tight and prevented the whole mess. I learned a valuable lesson that day. It is okay to trust others to work on your vehicle, but it is a good idea to inspect things afterward. You never know when someone might be having a bad day. Even the people you trust the most can make mistakes."
"In the '80s I had a 74 Gran Torino. I needed to change the rear shocks. I may have been putting on air shocks. I was a teenager and couldn’t afford to have anyone work on it.
Anyway, I had the car in the backyard of my folk's house. I used the car’s bumper jack and jacked it up. I also had some stands under the frame too. I didn’t pay too much attention but I noticed it started to rain. I was twisting on a shock and all of a sudden I became aware the car was starting to sway. It was slipping sideways off the jack! I had left too much pressure on the bumper jack.
I grabbed the car before it could completely unbalance, and started yelling for one of my brothers or sisters to come out and help me stabilize it. Due to the rain, no one was outside. I didn’t think I could hold on for very long. It wasn’t heavy but I knew it would fall if I let go. The only solution I could come up with was to try and lunge out from under. I tucked my legs under me, let go of the car, and pushed off out the back as quickly as I could. I didn’t get very far. The car came down on me. Right on my back. My legs still tucked under me. I tried lifting the car but no luck. I was not going anywhere, so now my shouts were even more frantic. Finally, after what seemed like hours but was more like 10 or 15 minutes, my brother heard me. He yelled for my dad and they put the jack under the car and jacked it up off me.
I was hurting. The circulation to my legs had been cut off so it took a bit for it to return. When it did, it was like fire. The car’s fuel tank came down on my back. It absorbed most of the impact so it was just the weight of the car holding me down. It had a big dent in it and I had some nice scrapes on my back, but that was it.
I finished the shocks the next day. This time I put the car on solid ground and made sure I completely removed the bumper jack."
"This is one story my wife will never let me forget, and thank (deity of your choice) this was before the days of digital photography. I was a shade-tree level mechanic at the time, tuning up my shipmate’s ’65 ford t-bird. The front end was up on ramps, in park, and parking brake set, as I was dialing in the idle speed and mixture under the hood. Now this car had pretty high mileage and the shifter linkages were fairly sloppy, but I was confident with the brake set I was going to be ok. Unknown to me, however, some genius at Ford MoCo came up with the bright idea to make the T-bird idiot-proof by installing a vacuum switch in the shifter so when taking it out of the park, it would automatically disengage the parking brake.
Well, that’s what happened when in one second I had a carburetor under me, the next moment it was gone. The car rolling backward off the ramps. With the driver’s door open. I bolted after it planning to hop in and hit the brake. It bounded across the street in reverse, crashed through the neighbor’s wooden fence, bent the driver door forward against the front fender. Once clearing the fence, the steering turned to full lock right and the car made a perfect u-turn around the guy’s above-ground pool and I managed to get it stopped a few inches from another section of his fence. About five minutes of horror, we all had a good laugh over it, my buddy had the car booked for a new paint job the next week, so I scared up another door from the boneyard and dropped it off with the body shop and paid the difference to get that fixed, and I learned how to fix a fence. And never trust a ford T-bird parking brake."
"I’m not a mechanic, but I’m mechanically inclined and can handle most car repairs myself. The stupidest thing I have ever done was something that I knew better than to do but did it anyway.
I was getting ready to leave work one day and my car wouldn’t start. Wouldn’t even turn over…just clicked. I left something on and killed my battery. I worked at an apartment complex and had driven a golf cart around all day. A 48V golf cart that had eight six-volt batteries. I knew all I needed to do was isolate two of them, hook up my jumper cables and I’d be home free.
But that’s not what I did. I hooked it up so I got the full 48V. Figured I didn’t feel like messing with it and what’s the worst that could happen? The worst turned out pretty bad. I turned the key and it immediately started sizzling. Everything started smoking. All the lights went bright then instantly black. I shut it off and jumped out.
The car (a little station wagon) was a smoking, stinking mess. Bright copper was showing through where the colored insulation had burned away. I shut the hood and called my wife to pick me up. A few days later one of the painters was there and we were talking about it. He wanted to know what I was going to do with it. I told him I’d probably junk it, I was not going to spend the money rewiring the whole dammed car.
He asked if he could have it and I said sure. He had it towed to his house and a few weeks later he came into my shop and tossed something on my desk. Some kind of mangled blob. I looked at it and asked what in the world it was. It was my 'in the tank' fuel pump. Melted and swollen. I guess it’s a miracle I didn’t blow myself up."
"It was the early 70s, and I was working at a local gas station just starting my career as a mechanic. I was tasked with tuning a 1965 caddy. The owner was a former mayor of the town.
Cars from that era were simple to tune but many of them had gas filters in a glass bowl near the carburetor. Genius idea right? Put a bowl of gas right on top of the engine. What can go wrong? Well, plenty. It was winter so all the bay doors were closed. I just finished the tune-up, changed the filter in the explosive device near the carburetor, and got ready to start it. There were a bunch of us standing around the car. I hit the key and it purred like a kitten. I was feeling pretty good about myself until I noticed the eyes on one of the guys standing in front of the car. They were as big as moon pies.
Suddenly everyone started running around, yelling at me to turn it off. As I did one guy came out of the back with a fire extinguisher and let it loose while others were opening the bay doors and pulling me out of the car to push it out of the garage. Unfortunately, even though I turned it off it was doing the 'run on' thing cars did so often back then. So gas was still being pumped. These filters had a small rubber gasket between the glass bowl and the housing. I must not have seated it properly, so the gas just poured out of the bowl.
Well, we finally got it out before too much damage was done. But the plug wires and a few other items were crisped. It was obvious I was going to be there late that night replacing and fixing all the items burned up. One of the things I did from then on was to replace those glass filters with canister ones any time I had to tune a car that had them installed. I can laugh now but no one was laughing then."
"Many years ago, I was painting my Ford Limited Country Squire. I had bought it in Luton England while studying auto engineering over there. I had a problem with the main drive shaft while driving home from England. So, I decided to take it out to have its joint fixed. But I forgot about the auto gearbox. Big mistake. I was under the car and when I took out the shaft, I had a nice gearbox oil bath.
Went home, had a bath, and came back for more.
The hood was out, and so were both radiators. The shaft was back in place and I had just fitted new head gaskets. I was putting the engine back in one piece. I was sitting in the front of the engine, the radiators were, not yet, in place and I was fitting the distributor back in its place. I managed to find out, through experience, that you could fit the distributor 180º out of place. Big mistake. I was looking down the carburetor four venturies, because the air filter was not yet mounted. I asked my friend, who was inside the car, to crank up the engine. I just wanted to make sure everything, so far, was ok. Well, as you may understand, the engine did try to start, but because the distributor was wrongly fitted, some sparks managed to 'light up' the fuel with some intake valves open. A big flame came out of the venturies and I burned my eyebrows and some hair in my head.
Went home cleaned up again, and again, came back for more.
I did sit again in the same place and did put the distributor correctly, but did forget that one of the radiators was, or should have been, connected to the gearbox. Unfortunately, when I told my friend to crank up the engine again, this time, it worked perfectly. I was going to 'fine tune' the distributor position, and the two metal tubes that were supposed to be connected to the gearbox oil radiator, were just there, pointing upwards exactly to the place where I was sitting. It is not hard to imagine what went on, next. I got another gearbox oil bath through the tubes I should have connected, before trying to start the car. As I said, I was young and still learning. That day I did learn a few valuable lessons. One of them would be that if you take a bath in gearbox oil, It is not easy to wash it off"
"I started a job as a Service Porter for a dealership in town when I was 19. Easy money, $14 an hour, general shop work such as running for tools, moving cars, sweeping, and cleaning. On Saturdays, I was to help with oil service. And to top it all off, I was eligible for Union membership after three months.
Day one was easy, I got along with the shop manager and lead service advisor. I left feeling like I had won the lottery. Day two, I found out we were being bought out, and the union rep came to talk to the techs about how things were moving. Apparently, this was a popular rumor but no one had proof it was happening until then, with management telling us what to expect, and the new owners shaking hands. By the end of the week, my new boss was fired, the sales team vanished, and I was moving used inventory to another lot. To add insult to injury, I was now the de facto oil tech, as his son was having a medical emergency and was being taken to a research center two hours away for a period of several days.
I was extremely inexperienced in the job, my only relevant experience was being a greeter at Walmart in the tire center. I knew enough to help but to work on my own when I could count the oil changes I had personally done, on one hand, it was a difficult trial by fire. The sales floor was empty, however, service maintained business as usual for customers. I had a regular flow of customers despite taking approx. It was about 30–45 minutes on each ticket, double so for diesel vehicles. They had a technician come in to assist me on weekends and when it got busy, but I largely was thrust into the position.
Lo and behold, I made a mistake, working inexperienced and in a rush.
I came in after my weekday off with the assistance of a technician from another shop. I was to return to my posted job as a porter, cleaning the shop and moving vehicles. Before lunch, I was told to help out a customer, and drive them in their own car to their office up the road, as they couldn't wait. Once I arrived back, I was called to the service office. That van was one I worked on, and allegedly, the filter was not properly fastened, and neither I nor the customer noticed. He drove off, and right before he turned off the interstate, his engine seized, and he stopped. As he waited for a tow, another vehicle struck the rear and totaled both vehicles.
I was walked out of the shop, needless to say. Not only did I rashly neglect the job, but I also put a customer at risk. And I hurt bad for doing that. Luckily he wasn't injured, from what I was told he was on the grass, away from the van. Had he been hurt, I likely would have lost more than my job. I get distraught thinking about that, how I potentially could kill a customer through neglect, and instantly learned my lesson. After that job, I continued to work as a service tech, but after three months, lost that job after a poor sales season. A fault not on me, but still hurts to see on a resume. I likely won't service other vehicles again, not a stranger's at least. It was a terrible blow to my confidence as an aspiring technician and my reputation as a service tech in any capacity. I've luckily found a different career route, and hopefully, I can excel here as I have very good experience with no significant mistakes made in this entry-level position. Hopefully, fate plays favorably."
"I am not a mechanic by trade, just a guy with a toolbox and more foolhardiness than sense. And this goes way back.
It was a 1969 Volvo 144S with brown sludge floating in my antifreeze. This, I knew, probably meant a blown head gasket. I was a poor first-year Assistant Professor at a small college, and I couldn’t afford the several hundred dollars it would have taken to get it fixed. I bought a new head gasket and some gasket cement from the dealer and borrowed a torque wrench from a shop at the college.
There is a lot of disassemblies needed to get to the head gasket. Air cleaner, rocker arm cover, and finally the whole rocker-arm assembly must be removed. I removed the bolts holding the rocker-arm assembly, and, as I lifted it out, one of the pushrods adhered slightly to its rocker arm because of the oil. The push rod lifted, too, then lost its adhesion and fell down into the engine and out of sight.
You know that feeling you get in your gut when you’ve just done something really, really stupid (and expensive)? Yeah, that nausea + anxiety thing. That was me. So I’m probably going to have to have the car towed to the dealer (over 20 miles away) and pay even more to have the thing fixed. Oh. Shtick.
Well, something told me to continue working. I carefully removed the other seven push rods and laid them aside. Then I removed the cylinder head, and there, sticking up out of the engine block was my wayward push rod. You know the feeling you get in your gut when the weight of the world is suddenly lifted? Yeah, that little shtick-eatin’ grin and a smidgen of self-satisfaction thing. That was me.
Long story short (or maybe it’s too late for that): the rest of the repair went pretty smoothly, no parts left over after reassembly, flushed and replaced the coolant, and no brown sludge appeared in my radiator … ever … again. Happily ever after. THE END."