Another 6 volt charging circuit question(s)

[soth122003]

I went with an alternator following Sam's advice after my 2nd genny died for the same reason as the first. The armature failed. It is the only thing you really can't test at home. If all the other components and checks are good, it's probably the armature. At about $120.00 a pop, the alternator was the fix for me. Easy install and charges the battery at any RPM, it's been doing great for over a year so far. Not to mention that starter and generator shops are becoming more scare as the years go on. It is also gets more expensive as time goes on due to the lack of need for these services. In a big city there might be services available, but in smaller areas they are kinda drying up or the prices are increasing substantialy. Then it will be drive a long distance or ship your genny to get it fixed. If you got the money and care about originality, fix it. Fixed income or not to worried about using updated parts go with the updates. For me money and update as long as they don't detract from the cars appearance, I'll update. Just my 2 cents, wait inflation, 25 cents worth.

 

Joe Lee

[1949plymouthdeluxe]

I did what you did. I ordered a alternator. Spent a little extra and got the 100 amp unit. I assume you have to bypass the voltage regulator since the new alt has one built in. You are right- rebuilt generators are spendy. 

[Sam Buchanan]

7 minutes ago, 1949plymouthdeluxe said:

I did what you did. I ordered a alternator. Spent a little extra and got the 100 amp unit. I assume you have to bypass the voltage regulator since the new alt has one built in. You are right- rebuilt generators are spendy. 

 

Wiring instructions come with the alternator but it is a simple hookup. Discard (or tape off) the generator field and armature wires, they aren't used. The single wire from the alternator connects to the wire on the old regulator BAT terminal. You can either use the regulator as a terminal or discard the regulator and connect the alternator and BAT wires together. I tossed the regulator, added a fuse in that line to protect against the remote possibility of a short to ground in the alternator and connected directly to the car's harness. The red wire is coming from the alternator and the other fuse wire connects to the harness wire that was previously on the old regulator BAT terminal.

 

[1949plymouthdeluxe]

Oh that is pretty easy. What size of fuse did you wind up using BTW? Would 20-30amps cover it? Thanks guys. 

[Sam Buchanan]

Fuse should be sized for the wire, I have 30a or 40a, can't recall which, I'll try to check. Have 10g from alternator to the car's harness.

Edited September 16 by Sam Buchanan

[Sniper]

If you have an alternator and starter rebuilding shop anywhere nearby they ought to be able to handle that for you. You might have to go to the big city though probably should call First

[9 foot box]

   Roofus has his own way of testing a generator. This is the Service Manual procedure for a motoring test. The generator that is as clean as what you say yours is could be fine. The field coil in the regulator could be at fault, there’s a test for that too, it’s in the Manual. I could ground my field wire to show a charge, but it had to be grounded again every time I restarted. I replaced the regulator. 

[1949plymouthdeluxe]

After having taken the generator off an apart several times Its pretty clear something is up with it. I'm going to keep it anyway just in case. I really want to get the new alt installed and operating because after that I am going to overhaul the radio. I restore a lot of vintage radios and these are pretty neat. Looks like it uses basic 6 volt tubes which means there's a vibrator to supply the B+ voltage which would be in excess of 90+ volts. They also use as much as 2 amps so you really need both a good battery and generator/alt to work. 

 

Quote

If you have an alternator and starter rebuilding shop anywhere nearby they ought to be able to handle that for you.

Not as many people or places seem to want to or know how to work on these old generators. I looked around and it was going to cost over $250 for a rebuilt one. Most of the shops seem to not really rebuild the armetures which is a core part and a problem that often pops up. So alternator it is.

[1949plymouthdeluxe]

I installed the 6 volt alternator last night. It was straightforward but I had to take the bracket off several times to get it to fit right. I was confident in myself and decided to take the car to the grocery store. Started it up and I got a loud "TAT-TAT-TAT-TAT!" noise. Shut it off. One of the blades of the cooling fan was just barely nicking the end of the alternator pulley bolt. Took it off again, backed it up a little and problem solved. Maybe I am imagining things but seems like the car runs a little better. Not sure why. 

[Sniper]

The only thing I can guess is that the alternator puts out a more consistent system voltage. Your coil output is directly related to the voltage coming in so with the old setup as your voltage got lower the coil output got lower and maybe that made an effect on combustion happening or not happening.

Edited September 28 by Sniper

[1949plymouthdeluxe]

Yeah could be. I remember reading someone else I'm here he did the same thing that I just did and swore the car ran cleaner. But it could just be persuasive psychology or something. 

 

Anyway I drove the car all day today. Went to a bunch of stores went to the club that I volunteer at and it's starting real good and strong now so I think the alternator solved my charging and power problem. I just removed the radio and I'm going to start working on that next. But I'll put that somewhere else

[Sam Buchanan]

On 9/28/2024 at 9:17 AM, 1949plymouthdeluxe said:

I installed the 6 volt alternator last night. It was straightforward but I had to take the bracket off several times to get it to fit right. I was confident in myself and decided to take the car to the grocery store. Started it up and I got a loud "TAT-TAT-TAT-TAT!" noise. Shut it off. One of the blades of the cooling fan was just barely nicking the end of the alternator pulley bolt. Took it off again, backed it up a little and problem solved. Maybe I am imagining things but seems like the car runs a little better. Not sure why. 

 

 

Excellent, glad the alternator is working well for you. Most likely you will never have to address charging problems again.

 

I encountered the fan and alternator pulley nut interference, too. The nut is machined to where it protrudes quite a bit beyond the pulley, may have something to do with its original application. I changed to a slightly longer belt to move the nut outside the arc of the fan blades and all is good.