What's your stupidest mechanical blunder?

[BuzzStPoint]

Re: What's your stupidest mechanical blunder?

Changing valve seals on an engine..

I a real hurry I wasn't following the proper procedures.
I didn't put the cylinder at TDC, I applied air to the cylinder, but lost my magnet to hold the valve so I thought the air should be enough.

Pulled the spring clips off and pulled the spring, poped the valve seal off and I bumped the valve and "tink".

Valve fell into the cylinder. I went to the store bought a mini magnet and tried fishing the valve to get it back....

Anyone know what happens when you do this? Had to tear the cylinder head off the car.. Cost triples when you do something stupid like this.

 

[BuzzStPoint]

Re: What's your stupidest mechanical blunder?

In my younger years ( I was 20 ) I was using a pedestal grinder to break the sharp edges off a piece of 1/4" flat stock steel I had just cut. Well, there was a plate that was 90* to the open face of the wheel and it had a gap in it. Right then and there is where I learned you DONT EVER WEAR GLOVES around a grinder. The wheel "sucked" the steel through the gap and pulled my hand with it. I ended up cutting off my thumb. lesson learned

Not me, but my aunt. (farmers)
Disconnecting a PTO shaft on a tractor.
The equipment must have had some tension in it. When she pulled the PTO out it spun taking off 1/2 of her middle finger. Ouch...

 

[DECK SWABBER 58]

Re: What's your stupidest mechanical blunder?

I was in my mid 20's working in a auto repair shop. We had a
rear whl. dr. car that had a noise in the rear axle. An older
co-worker/mentor had me put a floor jack under the rear end
and start it up and idle it in gear. After he listened to it he said
ok lets take it for a test drive. I said ok and twisted the jack
handle and the car took off across the lot. Fortunately he was
on the drivers side and was able to run along side reaching
through the window to slam it into park just before it reached a
busy street.

 

[mommicked]

Re: What's your stupidest mechanical blunder?

I too had a job at a 3 bay garage my neighbor ran. i was 16.I had been there a month or so that summer and went to let a car down off the lift.the lift controller was on the wall and I was not watching the descent.I finally turned to chek the progress and saw the front end stood up on a trans. stand I didnt move far enough the cradle had caught the front bumper!!the car was about 45 degrees!I gasped and raised it back up and it was fine, slight damage to the inside edge of the bumper any further and it surely would have slid and fallen off! at least the garage door was was open!I told the boss what i had done and he scolded me and laughed.he didnt ask me to jack or lower any cars for a while.and said the damage was ok. it was an older car of a friend of his.

 

[mommicked]

Re: What's your stupidest mechanical blunder?

One more and Im done.18 dad helped me buy a 72 toyo landcriuser 3 inch lift 33s and a spun rod bearing.pretty good deal $1200. we rebuilt the big 6 inthe the back den in the house,didnt have a garage.we noticed the rotating assembly seemed tight when we rotated it but we thuoght it was ok.4 of us carried the engine w the head on it, out the front door hanging from a steel pipe!cranked and ran at fast idle 20 mins.motor still seemed tight.dad took the wheel and we were off.about 20 mins later and 5 mi. away dad started given it the throttle good.I told him I think it needed to break in somemore first.moments later we stopped and the motor did too.locked up!after towing it home we removed the eng.and found the rear main bearing welded to the crank!seems the machine shop supplied the wrong bearings for the crank they machined.dad was pissed,i was heartbroken.we took it back and the shop fixed and replaced parts for free but we had to tear down and reassemble etc. again.this time in the driveway.i think we all got an inch shorter lugging that heavy motor on a pipe on our shoulders.it ran fine 2nd time around and I thanked dad for his patience in this endevor.one tough machine.got squirrely one day in the mud showing off w my girlfriend and lost control went staight 4 a 12/14" pine tree!to my suprise the the cruiser knocked the tree down w the front bumper and we rode over it!only damage was a slightly bent bummper!father/son projects are the best projects in my opinion.better still w/o stupididty!!

 

[Brewman61]

Re: What's your stupidest mechanical blunder?

How many have learned the hard way (busted knuckles) that you pull a wrench, not push it?

Way more times than I care to share. I've done stuff like that too many times.

Once I had a bolt snap off when I had my full body weight hanging on a wrench, and I was laying under my car. Elbow slammed into the concrete at mach II, hurt like hell. Being the hot headed teen I was, I launched the wrench across the garage floor, and it pierced thru one of those thin metal two gallon gas cans, so then I had an extremely sore elbow, and a fuel spill to tend to. Of course dad walks out into the garage just as the wrench hits the gas can. I got the look, a fuel spill mess, and an exremely painful elbow.

 

[SigSaurP229]

Re: What's your stupidest mechanical blunder?

I have had my fair share that's for sure. Nothing major though.

Lets see

I hooked battery cables up backwards on the boat that really sucked I lucked out no damage done, as I didn't realize it but the battery was allready shorted out, turned out to be my lucky day.

I had a 1997 Nissan 200sx that I bought wrecked, I didn't have a welder and the Hood latch was broken off of the radiator core support. My thought process align everything up drill through core support and hood latch and bolt it all together in the process of drilling through the core support I went right through the radiator as well.

 

[LadyFish]

Re: What's your stupidest mechanical blunder?

This is a great thread!

It's nice to see guys own up to their mistakes or blunders and look back and laugh about it.

Keep them coming, some of these are a hoot, others well...my sympathies go out to those of you that were hurt or suffered permanent damage.

 

[contractorguy]

Re: What's your stupidest mechanical blunder?

15 gauge airnailer... (little T head nails), nailing into some very hard old lumber...

I had to press down on the gun to get it to sink..

Reaching way over a counter, basically all my weight pushing down on the gun, left hand gripping the front of the gun.

Fire the gun, The nail only went in about 1/4", the gun flew up off the nail, lost my grip and balance...left hand was still pushing down... trying to catch my fall...

I stuck about 1" of that nail right into the side of my palm....HEAD FIRST!!

Took me a couple minutes to get the strength to pull it off the nail...nice lil puncture wound





Here's another classic--
My cousin was giving one of those 'demonstration' speeches for his HS speech class. He was going to show how to change the oil on a truck.

He crawls under it, drains the transmission(it was a manual w/drain plug), changed the oil filter, then poured 5 more quarts into the engine

I guess he didn't even realize it till it started smoking on the way home lol..

 

[tswiczko]

Re: What's your stupidest mechanical blunder?

Lets see here.
Using WD-40 to find a vacuum leak on an engine with bad plug wires ? no.

Using a lighter to find that leak on a propane line ? no.

Heliarcing in a short sleeve shirt ? no

Using a cutting torch over head while wearing farmer john bibs ? no.

Holding the trigger on, on the nail gun while framing, and didn't let go of the trigger and put a nail in my thigh ? no

I think the worst mistake I made was when I was twelve. I was playing outside and wandered over to where my Dad was welding, I watched for a while and asked if I could help. He said sure so I climbed up on the frame he put a welding helmet on me and handed me the stinger, He hadn't noticed I was running around barefoot, the transformer in the welder hummed I peed myself and he immediatley realized what was happening and swatted me off the frame with his burly forearm and sent me flying, broke a rib or two in the process.

Lets not forget when you can't see the position of the jackstand don't reach in there and feel around to make sure it's in a good position or your brother might let the car down and trap your finger between the frame and the stand, like mine did.

I have others but their too embarassing to mention here.

 

[bigdee]

Re: What's your stupidest mechanical blunder?

tailpipe extensions made from PVC pipe...looked pretty cool for 10 miles then it was two black noodles dragging the pavement. Sometimes a shoe string budget can get you in trouble!

 

[steve riddell]

Re: What's your stupidest mechanical blunder?

when i young , dumb & full of ... I had an older reinell with an omc stinger. we were cruisin along, then all of a sudden NUETRAL I backed of the throttle & tried again, the boat moved abit, then NEUTRAL again.
havin heard these legs were crap i removed it, replaced just about every thing in the leg(costing me thousands) put it back together, went to try it out, idled out of the no prob, went to give it gas NEUTRAL again.
Ended up being a spun prop hub that cost me $50 to fix!!

Ya cant fix stupid!!