Don’t make these 6 mistakes when working on your car


Working on cars is hard. Certainly not as easy as some of us wish. We posed a question on the Hagerty Forums last week and let our readers respond with their stories of the dumbest mistake they made while working on their car. There was plenty to learn from, and maybe a few to laugh at, in the numerous responses that our members had the confidence to type out. Here are a few of the trends we pulled from the responses.

1. Dropping items in places they aren’t supposed to go

The Worm to the rescue!
The Worm to the rescue! Rob Siegel

It’s almost as if Rob Siegel was reading the collective car enthusiast mind when he wrote  about how to retrieve dropped nuts and bolts that disappear into your engine last month. Ranging from washers down intake manifolds to a wrench finding its way into a frame rail, it seems no mechanic should be embarrassed about dropping things, because we have all been there.

2. The leftover parts

Tools and parts on a workbench
Mike Drilling

Getting the engine back in just to find yourself looking at the oil pickup tube on the workbench is rough. The remains of a pilot bushing found on the floor after tightening the last bolt on a clutch job is even less fun. Leftover washers are one thing, but fully formed parts and bolts should be a cause for concern when examining the quality of your repair.

3. The double gasketed oil filter

Oil filter

Oil changes are often where people start in doing their own maintenance, and for good reason. It’s an easy process on many cars. Simple as it may be, removing the oil filter sometimes leaves the filter gasket stuck to the engine block, making a double gasket seal when the new filter is installed. That extra seal is bound to fail on first startup, leaving you with a little or a lot of oil to clean up—depending on how long it sprays before you see the error of your ways.

4. Drained the transmission instead of the engine

Draining motor oil

Modern front-wheel-drive powertrains (and even classic ones, looking at you Toronado) can look mighty confusing from underneath, so pulling a drain plug can be a little bit of a gamble if the mechanic is going about the job absentmindedly. You might end up buying some transmission fluid to go with that fresh engine oil.

5. Make sure it’s in park….

Wheel Chock
Ulrich Heither

Whether while the car is on a lift or when you are walking back into the garage for that quart of something to top it off, put the car in park or make sure it is chocked in place appropriately. Tales of cars running away from or over the owner ought to engrain this one in your brain for a good long time. Self-driving cars might be a part of the future, but make sure it isn’t your classic.

6. Secure your tools

Removing Louie’s clutch master cylinder with a crowfoot wrench ratchet attachment. The just-replaced slave cylinder is seen at upper left.
Rob Siegel

Test firing an engine can reinvigorate a tired mind (or spirit) to finish a project. It can also lead to that project growing in scope. A socket in the intake valley of a V-8 will rattle for a bit, but a wrench falling from the core support will bounce off the cooling fan and puncture your radiator. Not ideal.

So keep these six themes in mind next time you are wrenching on your project. It could save you some time, money, and your health.


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