Belts don't generally fail because you 'overwork' the alternator. It's usually the alternator that fails, and usually that's just the electronics in it. For a belt to fail something has to either be grossly out of alignment or seized. Alignment issues often manifest themselves by excessive squealing noises. The belt is being forced out of a straight path and that causes the sides of it to rub, producing the noise.
A seized pulley basically fries the inside of the belt. This usually makes a hell of a lot of noise and a lot of burned rubber smell and usually some smoke. It's usually easy to tell what's seized up if you check it immediately after the belt failure. Basically you manually turn all the pulley wheels and see which one isn't turning. Water and steering pumps, alternator, idler pulley (the thing that keeps the belt tensioned) and the crankshaft itself. Obviously you can't hand-turn the crankshaft, just crank the starter motor to see that turn. But everything else should very easily turn by hand. Just be sure to use something to protect your hand from any heat present.
It is NOT a normal situation to have belts constantly failing. It's a sign of a BAD mechanic to let that happen more than once without ACCURATELY nailing down the cause. They're just fleecing you by doing the job over and over. Find another mechanic or start learning how to do it yourself.
As to the electrical situation, it's not enough to have just a wire connecting things. That wire has to be in good enough shape (and properly sized) to handle the load put through it. It's possible for corrosion to allow voltage to travel, but greatly reduce the amount of current that can get through. As in, you can measure 12v everywhere but as soon as you try to draw any serious amount of power the corroded wire or connections kills it. The first step is to pull off the battery terminal connections and clean them THOROUGHLY. Then do the same to the terminals on the starter AND on the main battery switch. Closely examine the ends of the wires. If you see any corrosion in them then you're going to have to replace them. It's possible for corrosion to exist inside the bundle of wires inside a cable. You usually see this at the ends or somewhere along the wire where the insulation has gotten cracked or otherwise opened.
I've had situations where an internally corroded wire would work fine when things were cool. But when the wire heated up (due to nearby engine heat and load pulled through it) the circuit would crap out. Once it cooled things worked OK again. I could check voltage at either end and it was fine when there wasn't anything pulling a load. The only way I discovered which one was bad was by using a long enough, and heavy enough gauge, wire as a temporary replacement. I had to use it on three different segments until I found the culprit. It turned out to be a GROUND wire going from the engine back to the battery. Not a positive wire. Power to the engine went from the battery to the breaker panel and then to the engine. But the ground when back to the battery went through a buss bar in the engine compartment. It was one of those lines that was corroded internally and would not properly return the load when things heated up.
Remember, power has to return back to the battery via a ground. It needs to be just a large as the positive side for the circuit.
The discussion on how to properly size wiring for additional accessories is a long one. There's a lot to it. The size of the wire to AND from the equipment is crucial. Use too small a gauge wire and you'll overheat it and potentially damage the equipment. Then the batteries have to contain enough power to drive the equipment. You can't realistically expect to crank up a powerful amp using just the factory included battery and wiring setup. Then the alternator has to be able to effectively recharge the batteries. That and if you expect to run the engine in order to power the amp that also requires the larger alternator.
Plenty of people end up setting fire to their cars/boats due to improperly designed/installed add-on equipment. It's relatively simple to do the job right, but often requires more planning and expense than people think is 'necessary'.
I vote for bad/corroded wiring. I'm guessing some portion of the wires themselves are bad. It's sometimes easier to replace whole sections of wiring rather than spending a lot of time trying to fix what's in there.
_________________ -Bill Kearney, 2005 348 Vista
|