being stupid, while teaching...

[ashman]

A couple of weeks ago my 16yo daughter bought a 2001 Lexus ES300 as her first car. Like all older cars, it had a problem pretty much immediately, the alternator was bad.

I decided it was a good time to get her more familiar with her vehicle, so I had her change the alternator with my help. Alternators are super easy, so why not? She is a good listener, so is doing exactly what I tell her so this should be no problem.

Fast forward to hooking the wires back up to the new alternator and I casually mention "BTW, usually you are supposed to disconnect the battery before doing this. I forgot, but we'll be fine."

Get everything hooked up, have her go start the car and it starts right up!
"Um, dad, none of my gauges are working and it won't shift."

No power getting to anything other than the engine, and every time we start the car it gets harder, so obviously the battery isn't charging.

I spent the next hour checking fuses, pulling the alternator back out, and going to have it tested (it was fine), and generally trying to troubleshoot before it finally hits me that there must be an alternator fuse or fusible link somewhere that got blown. Yup, 100amp fuse marked "ALT" that I overlooked. Looking back, I can remember a small spark when we disconnected the positive lead from the alternator.

And that is how taking a shortcut (not disconnecting the battery) can turn a 20 minute job into a 2 hour job.

At least my daughter got 2 lessons out of it.

 

[tRustyK5]

Any other time you'd have been fine...lol

 

[K5wrench]

I puffed 2.. TWO regulators in the 27si 100 amp alternator of my m1009.
Back to Back.
Because I was too lazy to disconnect the battery cable.

 

[1-ton]

With an older vehicle you could have totally gotten away with it.. flash of spark and everything.

 

[sweetk30]

new stuff you shouldnt even use jumper cables . some car's can have problems after . i towed a few nissans to the dealers for this problem . 1 guy later sa me and said it was over 800 bucks to fix it .

jumper pack only anymore is the safe bet . . . and then only if you know what your doing .

 

[HankScorpio]

All the lessons in life that I truly learned from were the ones I learned the hard way. Well done.

 

[diesel4me]

I hate it when that happens.....
It's only when your trying to "teach" or worse,impress someone that's not mechanically inclined when you go to repair something,that things blow up in your face..(especially if its a member of the opposite sex)..
Doesn't matter if you did it 100 times before,and could do it in your sleep..
Add an audience,and watch what happens..the onlooker who thought you knew "everything" sees you mess something up badly,and hears you say "hmm--never had THAT happen before!..

This is why I don't volunteer to help anyone with a vehicle newer than Y2K--one goof even jump starting someone could land you in court if you flash a computer,etc..don't like working on other people's vehicles or equipment either,especially if your being paid for it..they will blame you for every failure it has the next 6 months,even if you never even looked at the part,or worked on the end of the vehicle its located on..
I know a guy that offered to install a trailer hitch for a "friend"--he was only going to charge $50....but he used his arc welder to zap it on in a few spots in addition to the bolts,to make it fail-safe..then the truck wouldn't start when the owner came to pick it up..welder fried the ECM,and it was a $500 bill at the dealership to make it run again..he didn't get his $50,and was taken to small claims court and lost,he had to foot the repair bill..

 

[diesel4me]

Thinking about this post last night brought back a memory from my high school shop class days..

One day our shop teacher had us all gather around,to show us a "new invention that will make power tool use much safer"..
In his hand,he had a new Black & Decker "double insulated" drill..
Supposedly it was near impossible to get a shock from this new drill,even if the motor shorted out--it had a plastic case,only the front part near the chuck was die cast metal,with a rubber coating on it..

He plugs it in,and goes over to a wall,where he was going to drill holes to mount a electrical box for circuit breakers,and show us how to wire one up properly..

About the third hole,the drill broke thru the wooden wall,then seemed to labor,like it was drilling into something tougher..
Suddenly,there was a big flash and a BANG,and the drill just about exploded in his hands!..smoke and flames belched from the drill motor,and then that part of the shop went dark, when the fuse blew..
The shop had those big shotgun shell type fuses that went "POW" when they blew..it was awesome..

He had drilled right into a 3" electrical conduit hidden inside the wall,which carried the thick cables to the shop air compressor,which ran on 440 volts!..and two 220V wires for nearby outlets used to power the janitorial equipment like floor buffers and vacuum cleaners..

Needless to say he turned beet red,and the fact all of us were splitting our sides laughing didn't help...he ended up getting pissed at us and told us all to "shut the hell up" and the next guy who laughed would get detention...a few did,and said "it was worth it!"..
He had some explaining to do,when he went to return the new drill to the carpentry shop..it was roached!...."But I didn't get a shock"--he said he'd have been electrocuted had he been using an ordinary metal cased drill..pretty impressive "demonstration"..