318 alternator wiring

So I bought this used, running 318 to replace my cracked block 318. Hooked everthing up and got it running in my boat(see hydraulic valve lifter post). Just 2 wiring harnesses that plugged right in and it is running like new so I figure this is golden. But I don't think I'm getting any charging. I look at the "bat" wire from the alternator and it is cut and taped. The "fld" wire from the alternator goes to a metal box about 1/2 inch thick by 3 inch square (voltage regulator?). It attaches to a post on the box. The red wire from the "box" goes to the positive post of the coil. The box is free floating right now. I hooked up the batt wire to the positve solenoid post(where it belongs according to a wire diagram) and am getting 13-16 volts at the dash voltmeter it increases with increased engine speed. My question is:
1. Is the metal box a voltage regulator?
2. Does it need to be grounded(it is not right now)
3. If I hook the orange batt alternator wire to the positive post and ground the box will it work properly?

1. Is the metal box a voltage regulator?

Yes

2. Does it need to be grounded(it is not right now)

Probably.

3. If I hook the orange batt alternator wire to the positive post and ground the box will it work properly?

All wires on that setup need to be hooked up for it to work. A better fix is to buy a one wire alternator and toss the regulator out. All you need then is to hook up the large wire that goes to the battery.

Jeff

PS: An alternator rebuild shop can make yours a one wire will rebuilding it. Not as expensive as you think, it'll be virtually brand new, and the end of your problems.

I hooked everything up the way it says in the book. "bat" wire to battery, fld to regulator, regulator to to +coil, regulator grounded but it still charges at 16+volts. If the regulator is bad will it charge as described or not charge at all? One other thing, the manual says a resistor should be in line from the coil to the regulator. I don't have one there but the original owner switched to electronic ignition. Is that resistor needed for electronic ignition? I don't want to spend any more money if I don't have to on a new alternator. This is a second boat and the wife complains that we spent enough.

A voltage regulator box's only function is to LOWER the voltage coming from the alternator as the battery reaches full charge. It sounds like yours is shot.

On the electronic ignition system, that is another issue entirely. The stock setup uses a lower voltage (about 9 volts) coil with a resistor to achieve that voltage while running. During cranking, however, a full 12 volts hits the coil to improve the spark. Many people have tossed out the low voltage coil and ballast resistor to go with a "normal" 12 volt coil. Maybe the previous owner of yours as well?

Jeff

Thanks Jeff. I have a voltage regulator from my old engine so I think I will swap it out and keep my fingers crossed. I just can't figure out why the previous owner would cut the batt wire and tape it. Unless he had the high charge issue too. But how could he have charged the battery? Since the alternator does put out 16 volts can I assume there is nothing wrong with it? I swapped out my old alternator as well and it had the same symptoms so I don't think it is an alternator issue.

Anything over battery voltage after the motor starts says SOMETHING is charging the battery.

Jeff

So I swithched out the voltage regulator and got the same problem. Is the coil + terminal supposed to supply voltage to the voltage regulator or does current flow from the regulator to the coil? When I check voltage with a voltmeter at the +coil to ground I'm only getting 10-11 volts. Is that normal? My point is can I use any 12 volt source to supply the regulator or does it have to be the coil? I know it has to be on only when the ignition is on. I'm wondering if I'm not getting enough voltage to the regulator. The battery voltage reads 12.5 -13. Also, while dinking around with the key on the coil got warm without the engine running. Normal?

Electrical problems are frustrating. I think the 1 wire alternator is in my future. One wiring diagram says run the red wire from the voltage regulator to the coil but I'm only getting 10 volts there with the key on, engine not running. This is where it is now. A different diagram says run the red wire to the "on" position of the ignition switch. I'm getting 11.5 volts there so that may help. I will test it this weekend with the engine running and hopefully solve the problem.

hook the red wire from the VR up to the 12v ign terminal on the ballast resistor. So that the red wire has 12v when ign is on and try it.
The way you have it now the regulator is seeing the reduced voltage after the ballast resistor and trying to compensate.
The original installation 12v went through an oil pressure switch prior to powering the VR.
Joe

Well, I'm making progress I think. First of all I started the engine and checked voltage with a digital handheld voltmeter it read 14.8 volts at the battery while my gauge on the dash read 16+. I thought, "can all my trouble just be a bad gauge"? I bought a new gauge and it reads just over 14 volts from 1000 rpm- on up. 14.8 still seems a bit high though. Any thoughts on 14.8. Is that still too high?

No. THat's just fine on start up. Watch it for a while and it should drop about a 1/2 volt or more. If it doesn't, though...

jeff