So the mechanic from Catepillar gets up here Monday evening. Of course he does not speak English, so I'm working through a translator. People are still clinging to the belief that it is that "little black fuse" that is causing the problem. Oh yeah, and it's on back-order.
Next morning, the word comes back to me: It's the computer. Fried like an egg. Somehow, moisture got inside this supposedly-sealed unit. The corrosion is unbelievable. So is the *big* burn mark on the printed-circuit board where something shorted-out big time. (My guess would be the circuit that controlled the fuel pump, but what do I know?)
Yes, I feel vindicated. But this is not rocket science. I have so far downplayed my mechanical abilities, mainly because I am not a trained or licensed mechanic but just someone who's spent a lifetime working on mechanical stuff - not to mention that I do not have test equipment of any sort. But I am going to have to start being more assertive.
Our airplane is coming down on Friday (day after tomorrow) with a new computer. It'll be nice to have the front-end loader back in business. That is one useful machine, and it hurts the project for it to be unavailable for so long.