I am looking at a friend's truck for him. It has the biggest gas engine available in it but I'm not sure what it is exactly. I couldn't get the truck to spark from the plugs, and eventually determined it was the ignition coil at fault. I replaced the coil, and the truck started. I drove it around and it never died once and started up everytime yesterday. Today I went out however and it wouldnt start at all until I jumped it off. The battery and alternator are both brand new, it just seems like it's not getting the juice to turn it over. The fuel pressure is fine, I think this is an electrical issue. Could it be a problem with the voltage regulator and where is it located? And, also its rigged to start with a push-button start. I don't know what to do next and this guy is really hoping I'll come through for him. Any help is appreciated.

 

I believe the motor you have is the 460, but I'm not certain.

What do you mean by "jumped it off"? Did you have to jump start the truck, or jump the starter solenoid?

What do you mean by "it just seems like it's not getting the juice to turn it over"? As in, battery power? As in weak spark?

If you mean you had to jump start the truck, and "the juice" means battery power, I'm gonna say check and clean all of your battery connections. Meaning not just the positive and negative terminals on the battery, but the connections at the solenoid, starter, and body ground.

I'd also advise testing the charge rate of your new alternator. Anything less than 14 volts (I think- that might be 13.5) and it's no good.

 

First of all: Check the starter solenoid (it's the black cylindrical part connected closely to the battery and mounted to the fender, with a bunch of wires connected), to do so put the switch in the ON position, then get to the solenoid and bridge the threaded posts with any metallic object. If the engine turns then it's the most probable cause, you can either replace it or run it like this for a while, it seems like it isn't completely stuck, which could just mean it needs some use to release and it old self.

Other things to try: Clean the battery posts and terminals (leave them disconnected), get under the truck and clean all the connections at the starter, there is a small wire that gets dirty and causes the no-start condition, it's quite problematic at times.

 

Thanks for the reply. Yes, I jumped off the battery and it started. I have gone over the terminals and connections and they are fine. It is rigged to start with a push button connected to the starter solenoid. The truck will die sometimes once it gets running and doesn't want to start back up again. I think its getting a weak spark but don't know where to go from there. The alternator and battery are new as well as the coil. If the solenoid was the problem, why would it die after it was already running?? There is a fuseable link coming from the alternator, but I'm not sure what it is, just a fuse in the wire? I think the electrical system may be grounding out. The wiring has definitely been tampered with at some point. Not sure where to go from here. Any help is greatly appreciated.

 

A fusible link is just a fuse device in-line with a wire, just like you said. I would replace that fuse, whether it looks good or not. Check all connections to everything you can. Alternator and Battery circuits are often the same on cars and trucks. Check the wiring and make sure everything is wired up correctly so the alternator gets proper charging. If it dies on you randomly then a NEW battery acts weak then it's obviously not receiving charge from the alternator. If it dies and then cranks but doesn't start it lies in your ignition or fuel system. I have seen several NEW BAD alternators... check the voltage to it, like someone said it should be over 14V.