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'Flashing' the Generator???

Discussion in 'The Hokey Ass Message Board' started by ScottyRod, Apr 7, 2008.

  1. ScottyRod
    Joined: May 2, 2007
    Posts: 28

    ScottyRod
    Member

    I tried to search this out but I may not have the lingo correct.
    I have a 47 Ford with the origional flathead and ignition system.
    I was told that if the battery is disconnected for any lenth of time that the generator looses it memory of how to charge. This is when I need to 'flash' the system.

    I don't have a clue what I need to do.:confused: Could someone please let me know the proper proceedure for this. Me and electricity are not friends...


    Thanks!
     
  2. Petejoe
    Joined: Nov 27, 2002
    Posts: 10,582

    Petejoe
    ALLIANCE MEMBER
    from Zoar, Ohio

    the term is Polarize.
    Find the "B" terminal on the regulator and attach one of the alligator clips, find the "D" terminal and touch the terminal with the other alligator clip. You can touch the terminals a few times and it will produce a soft light spark. Under no circumstances touch the "F" terminal or any other part of the regulator or you could damage the regulator.
     
  3. Bruce Lancaster
    Joined: Oct 9, 2001
    Posts: 21,682

    Bruce Lancaster
    Member Emeritus

    POLARIZING A 2 BRUSH GENERATOR: Disconnect the FIELD terminal
    wire at the voltage regulator. Momentarily touch this wire to the BAT
    terminal a couple of times. Note: Failure to disconnect the field
    wire at the regulator (using a jumper wire) could overload the
    regulator and ruin it.
     
  4. Petejoe
    Joined: Nov 27, 2002
    Posts: 10,582

    Petejoe
    ALLIANCE MEMBER
    from Zoar, Ohio

    mmm. interesting.
    And here's more confusion information..

    Depends on the circuit in your generator. According to the Delco-Remy service bulletin dated 7-3-61, there are two different circuit types of generators:

    Type "A" circuit - The field winding is connected to the insulated brush inside the generator and is connected to ground through the contact points in the regulator.

    Type "B" circuit - The field winding is grounded inside the generator and is conncted to the armature circut inside the regulator.

    To polarize the generator with:
    Type "A" circuit - Momentarily connect a jumper lead between the regulator BATTERY and ARMATURE terminals after all leads have been connected, but before the engine is started.

    Type "B" circuit - Disconnect the lead from the regulator FIELD terminal, and momentarily touch the lead to the regulator BATTERY terminal. This should be done after all other leads have been connected and before the engine is started.

    I have always followed Bruce's way with good results with 1960-61-62 ford 12 volt generators
     
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  5. Bruce Lancaster
    Joined: Oct 9, 2001
    Posts: 21,682

    Bruce Lancaster
    Member Emeritus

    The two circuit patterns refer to ground path in different generators and alternators...I believe B to be correct for Ford (can recheck at home), and that jumper wire method raises the possibility of burning points in the regulator. Will doublecheck to be certain, but I'm nearly certain that removing field to flash is correct. Wrong way always comes up, because people working on other makes have learned that one...
     
  6. tommy
    Joined: Mar 3, 2001
    Posts: 14,758

    tommy
    Member Emeritus

    I always have to look it up every time. The Stude is Delco Remy and is different from the Ford. I can never keep 'em straight and I don't want to. I look it up every time just to be safe.
     
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  7. HellRaiser
    Joined: Jun 14, 2006
    Posts: 1,240

    HellRaiser
    Member
    from Podunk, NE

    When you do flash it, Disconnect the field post wire, and flash it to the "B" battery post on the regulator. Don't jumper wire it across though.


    HellRaiser
     
  8. stuart in mn
    Joined: Nov 22, 2007
    Posts: 1,809

    stuart in mn
    Member

    In my experience you may or may not have to polarize the generator. Wait until you get everthing together and start the car; if the ammeter needle jumps to the charge side it's working, but if the needle jumps to the discharge side you need to polarize it.
     
  9. Bruce Lancaster
    Joined: Oct 9, 2001
    Posts: 21,682

    Bruce Lancaster
    Member Emeritus

    From the NAPA/Echlin "Manual for the Automotive Electrician", edition circa 1955:
    Ford-Merc-Lincoln remove Field wire and touch to Batt wire momentarily; most other cars, touch jumper from Arm to Batt at regulator. For cutout 3-brush Fords, jumper between two terminals on cutout.
    Useta was each regulator had the instructions in the box, sometimes with a bit of wire for jumper included, and a set of little cardboard tags to label your wires when disconnected...
     
  10. Some n00b put a brand new 6v generator on my 48 and hooked it up with negative ground rather than positive...I've heard this is no big deal?
     
  11. Bruce Lancaster
    Joined: Oct 9, 2001
    Posts: 21,682

    Bruce Lancaster
    Member Emeritus

    Tracking down the Ford info was a real hoot...no mention of polarizing in any Ford text I could find 1938--56, no mention in the common aftermarket fix your Ford books or "Ford Electrical systems" from ICS!
    Found it in a couple of ancient parts stores manuals. Never had a problem in the past as the instructions were always in the trunk in the box with an old regulator...searching online led to about an even mix of right (F--B) and wrong, destructive (A--B) Delco style...
    So this process is wholly folkloric. Echlin says do it anytime wires are disconnected.
    I've never skipped it and so have no idea if polarity is actually likely to be wrong without it. I never met a mechanic who did not do it in the days when mechanics could still recognize a generator.
     
  12. Flat Ernie
    Joined: Jun 5, 2002
    Posts: 8,410

    Flat Ernie
    Tech Editor

    Not for early Ford. You'll be trying to motor the generator with the belt on if you do that. And while it would take a while, you could burn up your armature.

    Won't hurt a thing. If you want to change it back, swap the cables on the battery & re-polarize the generator as described above.
     
  13. 50flathead
    Joined: Mar 8, 2005
    Posts: 1,101

    50flathead
    Member
    from Iowa, USA

    "I was told that if the battery is disconnected for any lenth of time that the generator looses it memory of how to charge. This is when I need to 'flash' the system. "


    I purposefully disconnect all of my batteries in the winter. I know I won’t be using the car or truck for a few months and I cannot put a maintenance charger on it. I've never had a problem with the generator or the voltage regulator loosing its polarization and a disconnected battery will keep its charge better.
     
  14. Flat Ernie
    Joined: Jun 5, 2002
    Posts: 8,410

    Flat Ernie
    Tech Editor

    As mentioned above, there are two types of generator circuits. The procedure you provide is correct for the GM/Chrysler type-A circuit, but can damage an early Ford type-D circuit...

    EDIT: Here's what my Motors Manual says:

     
  15. Dan10
    Joined: Aug 14, 2007
    Posts: 386

    Dan10
    Member
    from Joplin

    I had a regulator go bad on my 60 ford. I talked to my pops, and he told me to re polarize it, and showed me how. I did it and it worked good on my 15 mile trek to school. When I came home from school, I pushed in the clutch and it died. Smoke was pouring out from the engine bay. I popped the hood and my battery cables were ON FIRE. I had inadvertantly soldered the connections together and was on full charge. Long story short, make sure that your amps drop after a while. I installed an ammeter after that lesson.
     
  16. Bruce Lancaster
    Joined: Oct 9, 2001
    Posts: 21,682

    Bruce Lancaster
    Member Emeritus

    Hmmmm...how did you polarize it??? Could your father have shown you a way he learned on GM cars?? I'm interested, because burned points in the regulator is the theoretical difficulty caused by polarizing a Ford the other way, according to the books.
    I've always wondered whether that was a real danger, possible in just flashing, or whether you had to seriously over-do the job to get damage. If it directly grounds something through points it might just french-fry them quickly...
     
  17. Flat Ernie
    Joined: Jun 5, 2002
    Posts: 8,410

    Flat Ernie
    Tech Editor

    Early Ford are internally grounded. Correct polarizing procedure is disconnect field terminal & flash it to battery terminal on VR.
     
  18. ScottyRod
    Joined: May 2, 2007
    Posts: 28

    ScottyRod
    Member

    Thanks fr the help. I was not sure wheather to do it with the car running or not, so I did it both ways. It made a little spark, so I was happy.
    I just hope that the generator is charging now, the old lady hates to push....

    Is there a 'test' that I can do with a test light to determin if the generator is charging?

    Once again, thanks for the input. I will try and post some pics soon.

    -Scott
     
  19. Flat Ernie
    Joined: Jun 5, 2002
    Posts: 8,410

    Flat Ernie
    Tech Editor

    Put a voltmeter on the battery & rev the car up - you're looking for 13-15 volts.
     
  20. Bruce Lancaster
    Joined: Oct 9, 2001
    Posts: 21,682

    Bruce Lancaster
    Member Emeritus

    The following is stolen from a post by one Mike V on the Fordbarn, who understands the theory and reasoning of this process:


    " ... Posted by Mike V. Florida from adsl-074-237-091-108.sip.mia.bellsouth.net (74.237.91.108) on Thursday, May 28, 2009 at 4:30PM :

    In Reply to: Re: Generator Polarity posted by FL&WVMIKE from 165.213.188.72.cfl.res.rr.com (72.188.213.165) on Thursday, May 28, 2009 at 4:02PM :

    A generator produces current by passing conductors (the armature windings) through a magnetic field. The magnetic field is produced by electromagnets that surround the armature. Basically, the field portion of your generator consists of copper windings around iron core, often referred to as the pole shoes.

    The voltage and current delivered by your generator is determined by the strength of the magnetic field and the speed at which the generator is running. But, the polarity of the current is determined by the polarity of the pole shoes, or the direction of the magnetic flux or field, which is determined by the direction of current through the field windings.

    OK, so you install a generator and take great care to connect the wires properly so you won't burn out your ammeter or cutout relay. What could go wrong if the wires are hooked up right?

    Plenty! When you start your engine, the generator will start delivering current. Since the generator is still isolated from the electrical system by the voltage regulator or cutout relay at this point, it will start producing current based on the polarity of the pole shoes. As soon as it begins producing current, some of that current will be directed to the field windings to strengthen the magnetic flux...."
     
  21. Bruce Lancaster
    Joined: Oct 9, 2001
    Posts: 21,682

    Bruce Lancaster
    Member Emeritus

    And a bit more, same guy, same source:

    "...According to John Deere's Fundamentals of Service manual manual, if the generator polarity is reversed, the generator will build up voltage and close the cutout relay points. This put the generator in series with the battery, and their voltages are added together. This high voltage across the points (about twice the battery voltage) can cause high current and enough heat to weld the points together.

    This damage does not happen immediately. The instant the points close, the voltage is about the same on both sides of the relay coil, so very little current flows, and spring tension reopens the points. But, generator voltage will again close the points, and the cycle will repeat at a rapid rate. Heat and arcing will finally weld the points together.

    When the points weld, the battery and generator are connected at all times. The low resistance of the generator allows the battery to continue to discharge through the generator. The high current can create enough heat to burn the armature.

    How do you control the polarity of the pole shoes? The polarity is determined by the direction of the last current through the field windings. Since even a very small current can polarize the shoes, never assume the generator is properly polarized. You must polarize the generator every time it is disconnected or serviced..."
     
  22. Bruce Lancaster
    Joined: Oct 9, 2001
    Posts: 21,682

    Bruce Lancaster
    Member Emeritus

    I never knew just why polarity was always suspect once gen or reg were disconnected...
    I just learned to polarize whenever messing with the things from ancient books...and of course in the old days, regulators and generators came with the proper instructions in the box, a set fo cardboard tags to ID the wires while loose, and, for GM regulators requiring it, a 3" bit of wire to use in the polarizing! The good old days...
     
  23. Bruce Lancaster
    Joined: Oct 9, 2001
    Posts: 21,682

    Bruce Lancaster
    Member Emeritus

    Yes, the first method is GM and most others, second is Ford 2 brush up til '63 or whatever.
    If you own a '42 Diamond T or something, you just have to follow the field lead out and puzzle through the diagrams in something like my olde Echlin manuals to figure out which religion your generator follows.
     
  24. Bruce Lancaster
    Joined: Oct 9, 2001
    Posts: 21,682

    Bruce Lancaster
    Member Emeritus

    You are basically interested in the wire coming off field coils; if a field wire attaches to the case at an uninsulated terminal (which is generally then wired to grounded baseplate of regulator to ensure proper grounding of both units together), it is Ford type also known as internally grounded/type B circuit/heavy duty circuit.
    If all field connections wind up at insulated terminals led to terminals on regulator, it is the other type, externally grounded within regulator.
    I am sure there are many old and odd variants as well as variants involving the various heavy duty generators available... I don't want to know about them. Distinguishing these two hurts my head enough.
     
  25. Okay, I polarized my generator on my '61 Mercury to the directions above. It charges until I shut the car off, everytime I restart it, the generator light comes on and it's not charging anymore. So basically I have to re-polarize it everytime I start it to get it to charge. What's going on with this, does it need a new generator?
     
  26. Bruce Lancaster
    Joined: Oct 9, 2001
    Posts: 21,682

    Bruce Lancaster
    Member Emeritus

    I have no idea whatever...but I do know that whenever automotive electricity does something strange, it is probably a ground problem! Rig up two jumper wires with alligator clips...use one to connec generator case to base plate of regulator, other to connect that direct to battery ground terminal. Reflash, start and stop, see if that does anything. If not a ground problem, next likeliest problem area is aliens up to no good.
     
  27. Ha ha, I'll try that. If it's not a ground problem, I'll just swap an alternator on it. Thanks.
     

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