620 Electrical problem-NEED HELP

[Datsun Parts]

OK so I am stumped with another 620 electrical problem. It blows the fusable link just after start up, it will remain running and is charging (high 14.5 on the volt meter) but as soon as you turn the key off it will not fire back up because the link is blown? This is the same lead wire that charges the battery too right? Because even though my volt meter is showing 14.5 V, its NOT charging the battery because that fuse is blown. Also, my brand new battery was down to just 9 volts this morning so something is draining it? Ideas, alternator or voltage regulator maybe? Anyone had this happen before?

[moparvwfreak]

sounds like the regulator is shot and your using a link thats too small. check your grounds as well. that could cause a link to pop as well.

[DanielC]

I would suggest that the regulator is actually good, and when the truck starts, the link blows, and the battery obviously does not charge. Meanwhile the alternator and regulator are happily putting out 14.5 volts, and the battery is actually disconnected from the electrical system.

[drxfter]

Sounds like a short in the starter circuit to me. If it starts, then runs with the fuse blown, then won't restart, then it's likely to be the circuit that powers the starter solenoid - and the same fusible link may connect the alternator to the battery to charge. Did you mean that it won't crank, or that the engine won't actually start? Possibly a wire shorted to the chassis or block, that makes contact once the engine's rocking?