starter or generator

cvicky

cvicky

Senior Member
my 55 Fairlane is converted to 12V and still generator
today it began cranking slowly when hot
when running it charging at about 13 and doesn't really change with lights on or when car is shut off
starters a couple years old reman
when the car is running and I take positive cable off car stalls
should a good generator keep car running without battery

??starter or generator
 
Measure the voltage across the battery terminals when the engine is off. Should be approx 12.5 to maybe 13 volts if the battery is fully charged.
Start the engine and with the rpm about 1500 measure the voltage on the battery terminals again. It should read around 14 to 14.5 if the charging system is working.
 
So....you converted it to 12Volts using a 1956 Ford generator and voltage regulator, right? Is the generator properly polarized?
 
cvicky said:
im 12.5 -13 all the time
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The charging system in the car isn't working correctly.

How recently was it converted to 12 volts? Was it working right before and now it's not?

Here's the procedure for polarizing the generator.
It can be done anytime the need arises and only takes a minute...

before you start the engine, remove the Field wire from the voltage regulator and quickly touch it to the Battery terminal of the voltage regulator (you'll get a small spark). This will polarize the generator, then reconnect the Field wire to it's position on the voltage regulator.

Note: in this diagram the (red / + / positive) "Battery" labeled cables are connected to the starter solenoid on the large stud terminal on the right hand side.
In your vehicle those cables may be fastened to the large stud terminal on the left side instead, it does not affect the function of the system.
 

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The best way to check a charging system is with it running and using a decent VAT tester. Sun used to make a nice one years ago. I like to check alternator/generator output not at the battery but between the UUT (unit under test) and the battery, this gives you the true output.

Hot weather is tough on electrics, be it the starter or charging device. How old is the starter, is it a 6V unit? When in doubt have it rebuilt if it is more than a few years old. I have a couple of auto-electric shops by me that are great.

Is the system 12V negative ground? That is always my preference on old cars. How old is the harness? Those were pretty simple but have no fuse panels, just fuse holders. I replaced the old crumbling harness on my '59, went alternator (63 amp) and high torque starter.
 
starts great battery fully charged
13V off or running with head lights on no change
take off positive battery CAR STALLS
how do I know if its voltage regulator
book says adj Field arm greator

i'll do polorizing but I think its ok because car started great for four years
new starter 2 yrs ago
original wire harness
12v negative grd
 
The voltage regulator is a self-functioning electro-mechanical switch that tells the generator when to turn on or off.
There is a way to test them individually to see which one isn't doing its job... but I don't know what it is.
.
 
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well it appears generators are not redly available no switches either,
now I know why every one switches to one wire altinater
where can I get a kit on a high school budget LOL
 
cvicky said:
well it appears generators are not redly available no switches either,
now I know why every one switches to one wire altinater
where can I get a kit on a high school budget LOL
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Quality Power in Yucaipa, CA

https://www.qualitypowerauto.com/catalog.php?category=148
GM 1 wire alternator is 100 bucks more or less depending on the output you want. But you should be able to get one almost anywhere. Mounting bracket is 45 bucks. Never have used one for a Y Block but I've used several of their brackets and alternators on flatheads with no issues.

Concours in Carson City, NV lists a Y Block bracket assembly that looks more specific than the universal one Quality Power lists. Its a little more money but it appears to have everything needed to mount the 1 wire alternator. https://concoursparts.com/
Concours is having a 4th of July 10% off sale right now. Code is FJ20
 
You can find the regulator adjustment in the shop manual, or probably any old Motors manual. But the next thing I'd be looking at is the brushes in the generator. Changing them was one of the first things I was taught for electrical systems.

It been so long, I really don't remember anymore.
 
how about wires switching from generator to altenator
I still have original 1955 harness with 56 12v generator
 
12 volt generator at rock auto is $46.00 + shipping. If you are getting 13v at the battery with the engine running I would adjust the regulator before going any further.
 
I had to file the ARM points in regulator
not sure what the adj should be
ARM points wr also discoloured
 

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If you decide you need the regulator a local auto parts store should have or be able to get one in a day or so.
Don't let them sell you the 6 volt part. '56 to middle 60's Fords can/may use the same 12v regulator.
 
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