One wire alternator help

69furyIII

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Hello I just purchased a powermaster 95 amp one wire alternator, I know I don't use my field wire, voltage regulator and original battery charge wire, all I do is run a charge wire from alternator to positive of battery, my question is I have a 16 gauge fusible link, do I have to get a bigger one and what else need to be done for this setup, thank you
 
I would use at least 8g wire from the alt to the battery, you shouldn't need to change any fusible links
 
At that amperage I would step up the fusible link.

I’m sure I don’t have to tell you - but running that kind of amperage through an old car on original wiring is a winning ticket to a electrical fire. Is there any reason the stock 45 or 60 amp. isn’t enough?
 
Ok I have a 6ga. Charge wire it's 7 ft long, so even though it's high amp alt. I don't need to upgrade the fusible link, and since I'm not using original charge wire should I still disconnect from the ammeter under the dash.
 
I went through a stock type alt in 2years , so I wanted to up grade, plus my dash lights and headlights dim at idle so I figure the extra amps would help out, and later it like to go with electric cooling fans. Ya the fire risk makes me nervous, that's why I'm asking questions.
 
I don't remember everything that runs through the amp meter, but it's good to bypass it
 
I went through a stock type alt in 2years , so I wanted to up grade, plus my dash lights and headlights dim at idle so I figure the extra amps would help out, and later it like to go with electric cooling fans. Ya the fire risk makes me nervous, that's why I'm asking questions.

They recommend a #6 wire for a 4' run for the 95 amp unit. The 95 amp unit is also probably serious overkill. You should always have a fusible link rated at the output of the alternator on the lead running direct to the battery. You do not need to change the existing fusible link on you vehicle as long as you running directly to the battery positive post or if you are wiring the lead to the cable post on the starter. You ammeter is probably not going to work using this type of setup.

Dave
 
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After initial start up, ALL voltage passes through the Ammeter before it heads to the master splice.

Bypassing it is never a bad idea. You’ll lose the function of your in-cabin ammeter but a voltmeter gauge is a handy tool to install.
 
The poor misguided.
You should have asked questions before you bought the wrong alternator. You will be lucky to get 2 years of normal pleasure car use out of the power master.
Of course dim lights are the fault of the stock altenator and not the 50 y/o wiring and it's connections. Hey, I understand, changing the altenator is easy and fixing and repairing a wiring harness is a lot of work.
Good luck, buy a good D.O.T approved fire extinguisher.
 
The poor misguided.
You should have asked questions before you bought the wrong alternator. You will be lucky to get 2 years of normal pleasure car use out of the power master.
Of course dim lights are the fault of the stock altenator and not the 50 y/o wiring and it's connections. Hey, I understand, changing the altenator is easy and fixing and repairing a wiring harness is a lot of work.
Good luck, buy a good D.O.T approved fire extinguisher.
Never had a problem with mine

1460137874015.jpg
 
Hello I just purchased a powermaster 95 amp one wire alternator, I know I don't use my field wire, voltage regulator and original battery charge wire, all I do is run a charge wire from alternator to positive of battery, my question is I have a 16 gauge fusible link, do I have to get a bigger one and what else need to be done for this setup, thank you

fusible links need to be 2 AWG sizes smaller than the wire they're protecting. To wit: #6 AWG requires a #10 AWG fusible link. Cut it 6 inches long and be damned sure to use fusible link wire for this and nothing else. I use a split brass bolt (oft called a "kerney") to join my battery fusible link to my alternator wire. W a 60 A alternator, I use #8 AWG w #12 AWG fusible link wire at the end where it goes to the top positive post on the battery. The kerney makes it easy to replace the link if it burns up, without all the pain of soldering a joint. I tape my split bolts over with 3M RUBBER TAPE, for electrical insulation, then CLOTH TAPE over that for mechanical protection of the insulation. This is the approved way of insulating split bolt junctions BTW.

I use another such for the lead FROM the battery + post to the dash via the starter relay. All my fusible links are joined to their conductor with split bolts.
 
The poor misguided.
You should have asked questions before you bought the wrong alternator. You will be lucky to get 2 years of normal pleasure car use out of the power master.
Of course dim lights are the fault of the stock altenator and not the 50 y/o wiring and it's connections. Hey, I understand, changing the altenator is easy and fixing and repairing a wiring harness is a lot of work.
Good luck, buy a good D.O.T approved fire extinguisher.

It never seems to occur to people that dim lights and poor charging weren't acceptable when these cars were new (nor was overheating in traffic, hard starting, etc.). Thus the "cure" might be diagnosing the real issue.

I'd go on, but I'm scheduled for surgery to replace my no-arch feet with some of these snazzy new walkers!

3362.jpg
 
Thus the "cure" might be diagnosing the real issue.
With exception of a handful of guys, proper troubleshooting skills are non-existent.
I've stopped trying to help because my questions that will lead to solving the problem efficiently get trampled by fifty Horseshacks and never gets answered.
 
At that amperage I would step up the fusible link.

Never play any games with a fusible link, it is not a fuse to protect your load, it's there to protect your wiring harness.

My Fury was serviced and the mechanic left the alt to battery wire close too but not touching the exhaust manifold. Couple days later, the heat melted the wire's insulation and it touched and welded itself to the manifold. The alternator was feeding a dead short, which if left alone would burn the cable between the alternator and the short and probably destroy the alternator. However the real problem, the battery feeds through the bulkhead connector, to the ammeter, to the master splice, back through the bulkhead connector and directly to the dead short. So all of that wire was instantly overloaded and within seconds would melt and most likely catch fire. By the time you figure out what has happened it's too late the car is burning. The fusible link melted virtually instantly, which disconnected the battery, which killed the ignition and stopped the motor and the alternator spinning. The fix was simple, repair and reroute the alternator output wire and plug in a new fusible link.

That happened while I was driving in the center lane of a three lane street and the car couldn't have gone from running well to totally dead any faster Never screw with the fusible link!

When you install your high current alternator, run the battery lead directly to the battery and install two suitably sized fusible links, one at each end. Why two you wonder, well visualize this. The cable runs from battery directly to the alternator and for some strange reason it gets pinched at the mid point and welds itself to the car body. If you have one fusible link at the battery end it will blow but the alternator will still merrily pump amps into the short and destroy itself. Ok, put your single fusible link at the alternator end, now the alternator will be protected, but the battery will pour all it's juice into the short. So the solution is a fusible link on both ends.

The second thing to do with your fancy alternator is rewire your headlights to use relays connected directly to the battery. There are handy kits that plug into the existing harness so that none of the stock wiring is touched. I forget the name, Big John probably knows. This use of relays to power high current items like headlights, cooling fans, etc. keeps all that extra load away from stock wiring harnesses and makes your car much happier electrically.
 
So can I run a charge wire directly to the battery when using a stock alternator, would that be better than going through the firewall.
 
So can I run a charge wire directly to the battery when using a stock alternator, would that be better than going through the firewall.
Exactly and do the headlight relay deal. All the existing wire harnesses remain as is.
 
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