Seafox, you make the case for "it if ain't broke, don't touch it."
Alternators and starters don't really require any routine maintenance
in normal use. What can a technician do? Bench test it? Replace the coils? Replace the bearings? Mainly, those are good or bad and they are normally allowed to wear until they show signs of failure, i.e. bearing noise
. I don't remember how long alternator brushes
last for, perhaps 2400 hours is time to change them but that's an easy job, no technician needed. If you think of it as 150,000 miles in car use--it might just be time to replace it with a remanufactured unit, forget the technician because there's not much he can do that a remanufacturing facility can't do better faster and cheaper. Heck, maybe just pull the unit, replace it, and keep it as a working spare instead of inve$ting in rebuilding it.
One friend of mine replaced the alternator in his car recently, after two shops both said "by the way, your alternator bearings sound shot". Another friend had no problems--till his alternator bearing seized, froze, tore the serpentine belt and ran him up a $200 tow plus the new alternator. (If that had been SeaTow, just add one more digit at either end., right?)
With a $5 mechanic's stethoscope you can peek around these things and get used to what the normal sounds are, then worry when and if they change.
Injectors and injector systems can be more problematic, but again, I think most folks ignore them till something is wrong--because it can be so easy to make them worse instead of better. Yes, dirty injectors can waste a lot of fuel/power. But for some of us, the cost of injector servicing would exceed the year's fuel use, and 2400 hours would be an awful lot of engine
time. I think I'd rather invest in fuel filtering, fuel additives, and a mutual "Don't Ask, Don't Tell" policy with the injectors.
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