voltage polarity

Hudsonrules
Hudsonrules Senior Contributor
edited November -1 in HUDSON
:mad::confused::confused:Need more help. The battery light is staying on, now one peice of information I have tells me to remove the field on the regulator and spark it against the bat on the regulator. I done that, no results, I read in the '49 shop manual that you jump from the batery side of the starter to the armature on the generator, still no charge, what is te right way? thanks Arnie

Comments

  • Unknown
    Unknown
    It is possable you have it polarized right and have another problem. I have a digital multimeter that will show which way it's polarized .-- it will show the voltage as a minus if it's polarized wrong
  • Geoff
    Geoff Senior Contributor
    You only need to this initially when installing a generator - it will not reverse polarity by itself, so if it has just stopped charging, you have a fault either in the generator or regulator.

    Geoff.
  • Hudson Grandpa
    Hudson Grandpa Expert Adviser
    Geoff is spot on as usual. For months I was having problems. Light on, fix Generator, lights off, not charging, (driving me nutso), buy a new regulator. Finally the garage that I took it to couldn't figure out what was going on. So they called a shop that does old cars, mainly 55-57 Chevys. They said take the Battery, Generator, and Regulator out of the car, and take it to Texas Alternator, or in your case one near you, have them put everything on the bench and test and line up everything to find out where the problem is. To me the biggest hassle was getting there and back. They had it done in 2 hours. 96.00 bucks. Generator had been overhauled by them, and they found out the problem was the new regulator that I bought from Napa was no good. Luckily I brought the old regulator along at that time. Brought everything back, reinstalled in the car, and 8 Volt Battery gets charged from the Generator through the old Regulator. Starts almost everytime, although I only drive it twice a week.
  • [Deleted User]
    [Deleted User]
    A tip that my granddad taught me years ago, and has proven right in many cases is " You can never have a ground connection on a 6 volt system too clean!!" (He was a Hudson dealer, and a top mechanic from 1933-1955). Ground connections are much more critical with 6 Volt systems than 12 Volts. This is especially true with overdrive relays, and voltage regulators which operate via tiny coil windings.



    You had previously mentioned that you had just painted the generator. You may want to be sure that you scrape the paint down to bare shiny metal on both the mating surface of one of the generator mounting legs, and the mount bracket on the engine. The generator case must be properly grounded to complete the circuit for the brush that isn't attached to the field coils. (see attached diagram from 1952 Mech. Manual).



    In your post when you first noticed the gen. light on, you had thought about replacing the regulator. If you have, or even if you haven't yet since the car has been sitting a while, you might also want to make sure the mounting surface on the body under the regulator mount pad that has the ground strap is scraped clean as well. Sometimes just relying on the threads of the metal screw to get it done just won't quite do it. This is true both on cars that are original with the normal road dirt/rust etc., and freshly restored cars that are detailed with new painted surfaces. It doesn't take much to create too much resistance to complete the circuit. After cleaning the area around the mounting surfaces, it is a good idea to dab a little dielectric grease, or vaseline on the bare metal to help keep the connection clean and prevent rust.



    While I was cleaning things up I would also do the battery ground strap connection at the engine mount, and at the frame, and see if that helped.



    I have seen guys throw a lot of money, parts, tools, and hair at a problem like this in the past, and it was just a bad ground that proved to be the cause.



    I hope this helps out.



    Dave Bean
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