Concise description of your best mechanical trouble

[davepl]

I'll give two examples, and of course, ones that might help people in the future are better. Only my second one meets that criteria.

In my '69 2+2 (call it an Impala SS427) I was driving cross-country and the battery kept overheating to where the sides were squishy. I stopped at a couple of shops along the way who confirmed the charging voltage was good, battery and alternator, and so on. Everything was perfect but it persisted.

It turns out I had one of those old Carter fuel pumps (the ones the 'click' instead of whir, and come on only when pressure drops). I think what happened is that the fuel pump would 'click' on for 1/4 second or however long, draw some decent amps, which would click on the regulator. If the regulator relay took longer to turn back off than the pump ran for, it'd charge longer than the draw persisted, thereby overcharging.

Ultimately I solved it by driving with my headlights on (this was early 80s before that was common). Later, I ditched the pump which solved it permanently.

[davepl]

And here's one that might help someone some day:

On the same car, when it got hot, I'd get a no-crank. Even the solenoid would not engage. Everything tested perfect, so far as I could tell. I'd actually turn the motor over with the fan for a while (no clutch fan) and sometimes that'd circulate enough coolant to get it happy again.

Later I discovered that I could turn the key to ON and then jump start the starter posts with a screwdriver. I had friends that knew that routine so well it was just part of driving. No shop could solve it, though many threw parts at it at my expense (ignition switches, starters, solenoids).

The problem turned out to be that I was a kid, so I added gauges. I included an ammeter, and I had installed that by inserting it into the big purple starter wire circuit. This also happens to be the wire that engages the solenoid.

When temps went up there just wasn't enough voltage making it (which a real shop would have caught, or I would have today) to the solenoid, but it all started with the ammeter. Since this has happened to other people (particularly when doing console conversions where you have to move the neutral safety switch) I figured it might help someone some day.

Short version: if your car won't even try to crank, check the voltage at the purple wire while trying. And if your purple wire has ever been cut and reconnected, it needs to be done perfectly or the wire replaced.