Did My Alternator Just Blow?

[Dsanduril]

If the alternator is old, and if it is driven by itself (no water pump) then sometimes is can be good to remove the belt as well when disabling the alternator. If there's electrical damage inside with lots of heat then there could also be bearing damage and stopping it from spinning just reduces chances of a problem. Of course, if you need the alternator pulley to keep the belt tight for something else (like a water pump) then that's a no-go, depends on the engine.

[belizesailor]

Originally Posted by fallingeggs

Turns out I was mistaken. Removed three wires. Third, I guess, being the tap for the tac.

Find a wiring diagram for the alternator in question. Labelling of connectors can be a bit cryptic and vary by make model.

Then have the alternator tested when you get to a location w a good alternator shop.

Sounds like a short to me too. I would want to isolate where. If you just hook up and go again then it may happen again. Could be a wiring harness short too.

[fallingeggs]

Tested the alt for a short (positive to frame) and didn't find one. Said what-the-heck and connected the alt wires back up. Sure enough, it works. Have RPM and charging. Guess it was only the starter. Why the starter would break 5 minutes after starting the engine, I don't know. Either way, I am happy to be running again with my spare. Was kinda looking forward to installing an alternator that actually charges, but oh well.

Just need two new bank fuses... currently directly connected. Other than the starter/alt, I think the only thing I am not otherwise protected against is a dead short of the batteries and they are only a year old.

PS - Will be in Sainte Anne or Le Marin in two days; breaking the trip up with a stop at am anchorage just north of Diamond Rock.

[travellerw]

Originally Posted by fallingeggs

Tested the alt for a short (positive to frame) and didn't find one. Said what-the-heck and connected the alt wires back up. Sure enough, it works. Have RPM and charging. Guess it was only the starter. Why the starter would break 5 minutes after starting the engine, I don't know. Either way, I am happy to be running again with my spare. Was kinda looking forward to installing an alternator that actually charges, but oh well.

Just need two new bank fuses... currently directly connected. Other than the starter/alt, I think the only thing I am not otherwise protected against is a dead short of the batteries and they are only a year old.

PS - Will be in Sainte Anne or Le Marin in two days; breaking the trip up with a stop at am anchorage just north of Diamond Rock.

Oh, if you are stopping in Grande Anse d' Arlet, don't hurry through (weather permiting). Those 3 Anses are FANTASTIC places to visit. Quaint, fantastic snorkling and beautiful. Unfortunately they can be crowded though.

Glad to hear you have your issue sorted. I have seen on multiple occasions where a starter engages shortly after the motor starts (internal short in the solenoid). The starter gear then couples with the motor and since the motor is spinning faster it burns the windings in the starter motor. Maybe this happened, but who knows.

Anyway.. Look forward to seeing you in St. Anne. It has actually gotten busy here the last few days with the good weather window. Still LOADS and LOADS of space to anchor though. We will be the loud boat with tons of kids running around (probably a good idea to not anchor near us).