You have every right to feel vindicated! Thank you for posting about it as well
I'm glad you stuck to your guns and got it sorted in the end.
I had a similar experience a few years ago with one of my project vehicles - a 1975 Datsun 620 ute (truck?). That little beast struggles to do 100km/h but it's virtually indestructible. I was having issues with keeping my battery charged and keeping power to my stereo (vital in my world..
) etc, so naturally I knew there was something that needed to be seen to. Under the bonnet they're a pretty straight forward 4 cylinder with nothing but necessities for the time. The biggest issue I had was that when I was driving, it would start running
really rough and the regulator would start "clicking" (almost like the sounds tappets that desperately need adjusting make) so I switched that out with one from another (unlicensed but running) 620 I have.
It did the trick momentarily, but the same thing started happening again. My Dad is also a mechanic and has a 620 himself as the workshop run-about (we're both pretty obsessed with these little utes lol) and his only suggestion was to replace the alternator - something I really couldn't afford to do when I wasn't even sure that was the issue. So checking it all over again, I noticed the plastic plug into the alternator wasn't as snug as it should be due to the brittle, old plastic deteriorating. The next time my baby started playing up, I pulled over and carefully wiggled the plug while he was idling, and what do you know - fixed! Only temporarily of course but at least I'd found the issue. Do you think my Dad would have a bar of it? No way. Best course of action was still a new alternator
Well, it's my vehicle and MY (lack of) funds.. so I told him I was going to switch out the plug with or without his help just to satisfy myself. If it turned out that I did need a new alternator - so be it - but I had to at least try, you know? So he gave in and actually
gave me the clips and connectors I needed from his stash. Though I think he was just humouring me
The next free weekend I had, I replaced the clip etc with the study new bits! I'm so proud to report that I've had NO issues since, and my little ute is still rocking his original alternator
Sadly, he's been parked up for a while because now he needs his drum brakes switched out and some structural rust seen to - but that was an issue I knowingly bought him with.
A bit of a disclaimer - I have
some recognised mechanical training and plenty of experience servicing (I was a Trades Assistant for a few years) and restoring cars so I do know how to
safely work with auto electrics.
Moral of the story:
Sometimes we actually do know our cars better than the men "qualified" in automotive diagnostics. Fight to test your own diagnostics (however you can - even if that just means being firm with your chosen mechanics) because even if you're wrong, you'll learn something. That's just my two cents