Question of the Week: What’s the dumbest mistake you’ve made working on your car?


Back around 1974, not being able to afford the needed automatic transmission rebuild in my 1967 Ford 289 station wagon, but having the strong back and average brain of an 18 year old, I made a $100 deal + my transmission with a local wrecker for a known good tranny, as long as I pulled it myself. Along with a friend, pair of jacks, and two big tree trunk sections for jackstands, it only took the entire afternoon to get it out with no damage to ourselves or the trans. Setting it carefully next to the one we’d pulled from mine the day before, there was a really long silence. Guess a little research would have shown that due to a changeover, the '67 model year used both aluminum AND cast iron cases, and driveshafts, and other things. Oh well, I got my $100 back, and the yard got a tranny lovingly pulled for free :frowning:


I was 16, just got my license & since it was Feb in Buffalo Ny it was freezing!

I ran out of windshield washer fluid so I figured I’d throw some water mixed with antifreeze until I could get to the store & buy more.

Well the 1st time I hit “Spray” it squirted a mixture of a slimy substance all over the windshield that only got worse as the wipers smeared it all over & totally blocked any view out the windshield.
It took forever for me to drain & clear the pump & lines from the antifreeze but at least my reservoir never froze up!


I put a new serpentine belt on a 64 Corvair engine and must have gotten the adjustment too tight. About a month later the engine started knocking bad, like I was throwing a rod. I was. The tension on the belt must have caused the outer pulley of the crankshaft vibration damper to separate from the inner, and the outer walked back into the oil filter and wore a hole through it, all the oil came out and that was the end of that Corvair for me. It was a $300 car in 1971, and I was 200 miles from home. Hitchhiking home was a lesson in humility.


Fortunately I never paid the price for my stupidity, but as a teenager I used to get under my Mustang when it had nothing holding it up but the scissor jack that came with it. Really dumb.


Hope that the car is garaged, otherwise moisture will build up around the foam!


Been there, done that. ONCE
Always check for the old seal on the filter when I take it off.

Another incident, accidentally stepped on the edge of the drain pan after draining the oil. Pan flipped over on to my leg and foot. You can imagine the mess it made.


Not having a cam timing belt tensioning tool when rebuilding a Lotus 2 liter engine. I had a Jensen-Healey that needed a head gasket. It took 72 nuts and bolts to get the head, intake manifold, cam housings, cam covers, etc off to the change the head gasket. I figured to leave the cam belt engaged but very slightly loose when I got it back together, and would tighten it while running to get it tight enough to not make any noise. Upon startup, it immediately skipped several teeth, and two of the 4 valves in one cylinder kissed a piston, flattening the valves and stopping the engine. I was so pissed I threw the 10mm wrench over the house.


Too many to list. Among a few of them:

  • Thought I was getting a “deal” on 20W-50 oil in the dead of winter, and using it.
  • Trying to trim the front air dam of my car with a RotoZip, instead cutting the live power cord and nearly electrocuting myself.
  • Not tightening the drain spout on the waste oil pan enough, and consequently getting a mini Exxon Valdez all over the driveway.


I must have a million of these, too, but here’s a not so embarassing, since I was kid, one. When I was 17, in 1984, I bought my friend’s uncle’s 1967 Chevelle SS 396 4 speed for $2700. It was a nice car, but it smoked at idle bad. I found another 396 for sale in the paper, bought it, and spent a weekend pulling the original motor out and dropping in the new one, which ran great. I then sold the original motor to a Corvette guy, who needed it for his '65 Vette. He called me a few weeks later and told me whoever worked on the heads forgot to install the valve seals, and he just replaced those and the engine runs like new. I drove the Chevelle a few years and sold it to some moron who offered me a ridiculous $3950 for the car. Can’t believe my Dad let me sell it.


At age 17 my Dad and I did a full tune up on a 1972 Charger. Forgetting to install the condenser in the distributor spent next 3 days in 110 degrees trying to figure out why it wouldn’t start !!