The most expensive car battery

One very cold winter’s morning, many years ago, my first car, a Mark I Cortina, refused to start. I rang into work to advise my boss about the situation and apologised that I was going to be an hour or two late.
No problem, as I had a battery charger. Because the garage had no power and was twenty yards away across a busy road, I had to disconnect the battery to carry it into the house to get some charge into it.
Suitable spanners in hand, I began the task of loosening the retaining nuts/bolts. Unfortunately, they were immovable. Not to worry ‘cos I had a can of WD40. Sprayed the nuts and left to soak for a few minutes. I returned to complete the job. The nut was still a bit stiff so I employed a bit of oomph! Not a good idea as the battery terminal sheared off. The other terminal disconnected easily.
I purchased new battery at,HAlfords. I was assured the new battery had a bit of charge in it, sufficient to get a vehicle to start up. Got it home, reconnected the connectors, turned on the ignition and after the first whirrrrrrr ... nothing. Disconnected again and carried battery over the road to home to put on charge for an hour or so. Telephoned boss and explained further delay.
Two hours later with the battery now charged and reconnected, turned on the ignition and the engine fired and swung into life. Success!
Got out to retrieve tools and drop the bonnet. Just as I closed the car door there was an enormous clashing sound over the sound of the still-running engine. What the hell???
At first, I couldn’t work it out. Where were my spanners? Found them on the ground under the front of the engine. As I reached under the bumper felt water dripping onto the back of my hand. I retrieved the spanner and searched for the leak. I wondered about switching the engine off, but would it start again? Then I spotted where the water was coming from. There was a hole in the back of the radiator. So, I switched the engine off. Only then did I spot the damage to the fan blade. There was a chunk of metal missing from its leading edge.
The vibrating engine block had dislodged the spanners from the top of the radiator. They had dropped onto the rotating fan. One of the spanners had hit the fan and was projected at force into the radiator.
I telephoned my boss again. His response was, “Come and see me in a day or two’s time when you get things sorted.”
So, after buying a new battery, having the car recovered to a garage, it was fitted with a new radiator and fan. I collected it two days later and was operational again.
“Another time,” my boss said, “please call out the AA.”

Which is why I’ll attempt to repair anything except a car.