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Is this new alternator right?

6290988

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I just picked up this alternator from Napa. It’s what comes up for 1969 plymouth 383. I’m not sure my motor is 69 though. It doesn’t look the same as the alternator I pulled off. I pulled two wires off my old alternator, I’m assuming this one would wire up the same.

5A1BA505-8C4F-4401-A278-FFC19B241832.jpeg
 
If you look on the ID pad by the dosteibutor it should say for example - D383 that’s tell you the year
 
So it is a 1969 Motor. Does it matter that I use this style alternator. This is the alternator that comes up for a 1969 Plymouth with 383 but it doesn’t math the alt I took off. Here is a picture of the output numbers.

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That should work fine as far as I know, maybe someone with more knowledge about alts will chime in
 
I'm getting old but it looks like it'll work as is. I don't see a 2nd field connection, it'll work just like ur original(dim hdlights @ idle) not much charging at an idle.
 
I'm getting old but it looks like it'll work as is. I don't see a 2nd field connection, it'll work just like ur original(dim hdlights @ idle) not much charging at an idle.

I circled both fields in red.

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On 69 and older cars you ground one and hook the green field wire to the other.Good to go unless you are looking to be period correct. The Square Back alternator is a newer style (and higher amps) that was not used in 69.70 up uses the 2 field wires and the one goes to ground in the Voltage Regulator. Not sure when the Square Backs came in to play.
 
Ok it is your lucky day! You got aN allmost DOUBLE efficient alt than the one original from your car. It is couple of milimeters wider than the original one.

That's a laters 70s and 80s alt not the first squareback series alt which looks on a side view the same than your original one. Your car will be HAPPIER with that alt.

It seems the brush for the field is already modified, getting cut the prong and mostly sure the isolation washer being replaced by a metallic one to be grounded. Prong was cut intentionally to not conect the field there causing a short. The earlier setups ( mech regs ) are regulated by positive, opposite to the post 70 alts ( 70/71 roundbacks included ) which get both brushes isolated being regulated by negative.

If you have the stock charging system without any kind if wiring jumper or bypass, I suggest run AT LEAST a wire straight between alt post and ammeter stud at black side straight through the firewall. Time to charging wiring and related parts mantenience
 
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Ok it is your lucky day! You got aN allmost DOUBLE efficient alt than the one original from your car. It is couple of milimeters wider than the original one.

That's a laters 70s and 80s alt not the first squareback series alt which looks on a side view the same than your original one. Your car will be HAPPIER with that alt.

It seems the brush for the field is already modified, getting cut the prong and mostly sure the isolation washer being replaced by a metallic one to be grounded. Prong was cut intentionally to not conect the field there causing a short. The earlier setups ( mech regs ) are regulated by positive, opposite to the post 70 alts ( 70/71 roundbacks included ) which get both brushes isolated being regulated by negative.

If you have the stock charging system without any kind if wiring jumper or bypass, I suggest run AT LEAST a wire straight between alt post and ammeter stud at black side straight through the firewall. Time to charging wiring and related parts mantenience

Okay. I thought the numbers would’ve been higher on this. Here is the link to the voltage regulator I bought. It’s the same one I had in the car before.

Couple questions-
-So a wire from alternator positive post to the black side of ampmeter?
-Should I do a heavier gauge wire from the alt to the voltage reg? Like a 10 gauge wire?
-Maybe an inline fuse to protect my system?


https://m.summitracing.com/parts/dcc-3690732

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1- yes AT LEAST that. Can be made more thought, from red post of amm up to starter relay stud but check the amm reading with just that initially.
2-yes. Keeping the existant stock 12 gauge in working order 10 on the added line is fairly enough.
3- no need for that. The existant stock fuse link on red wire is quite enough.

That reg is constant voltage regulator designed to race use ( per MP Specs ). However I don't have any opinion for it. I think for long time or highway use could not be healthy but regular use should be fine.

CHECK ALL THE CONECTIONS ON CHARGING SYSTEM INCLUDING AMMETER CONDITIONS ITSELF, meaning the gauge and isolation sheets ( ammeter uses one on each side of cluster housing ). This will require a cluster dissasembling. Time for deep check and mantenience. Bulkhead terminals conditions is critical on this.
 
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with time and heat caused by the lack of power coming from factory alt, the shunt inside the ammeter gets stretched, making to get loose the studs ( which are fit by pressure to the ammeter ). This increases the posible failure on isolations sheets and this is risky, able to get a BIG short there with cluster housing which is grounded

of course there is BETTER alts able to give more than 45-48 amps at 2000 rpms ( that is about 42-45 engine iddling ) which is way better, but you got that one without think on an upgrade, on same price rate than a "correct" 69 roundback alt. Correct 69 roundback alt is able to put around 45-50 amps as max output, being half at iddle. Your car will be gratefull with those 10-15 amps more idddling
 
aside that, you can get some small alt clearence with block. I had on my 74. Just fitted a longer belt and trimmed a bit the rear alt spacer. Of course my car is AC where the front alt brackes is smaller and allows lees play with the room there. Non AC alt bracket can allow more massaging fitting the alt
 
Just a heads up.
Keep an eye on that thing. I replaced mine last year with a Napa alternator and it lasted a month. When I took it back for a replacement, the replacement had a ding in the pulley as if it was dropped and landed on the pulley. I didn't like those odds 2 out of 2), so I got a refund and went to Advance.
 
Again ^^^^^ crappy replacement parts. Whatever happened to quality ?
How about pride in workmanship ?
 
I looked at a Nappy rebuilt alternator. Out of Mexico...thanks, but no thanks.
Took my old alternator down to a local shop, and had them rebuild it.
 
Lucky for you that someone in your area still rebuilds.Few and far between anymore.
 
We have a shop that rebuilds here in the Raleigh/Durham area in NC.

I decided to return that to Napa and picked up a round back style. I'm not running any thing aftermarket except the stereo and Vintage Air heater/defroster unit.

Appreciate the feed back guys.
 
Service manual also has all the gory details on how to work them, too. If your up to it.
 
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