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Generator and Polarity - Making sure Generator is Polarized Correctly

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Jim_Gruber

Jim_Gruber

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So the Generator Light on Bugsy IV is glowing brightly. I do not believe this 948 is the original engine in this BE. I had folks help me and they confirmed the coil is wired correctly for Positive Ground. For now I want to keep the Generator as Positive Ground. A Swap to an Alternator and conversion will come at a later date. However What I can't confirm is if the Generator is set up as Positive or Negative Ground. Remember the Generator Lamp is glowing at all times leading me to suspect I need to repolarize the Generator. Checking the with Google gave the following answer.

Polarizing Generator.
Look at the Generator. You should see a large brown wire and a smaller
wire connecting to a terminal marked F (for Field). Pull off the wire to
the Field terminal. Connect a short jumper wire to the large brown connection
(make sure you have metal-to-metal contact). Touch the jumper "lightly /
slightly" to the Field terminal on the generator. You should see sparks,
touch again (more sparks), and again (again more sparks). Now disconnect the
jumper wire from the large brown connection, and re-connect the Field terminal
wire. Your generator is now polarized.

There are just two wires, not a Large Brown Wire with a smaller wire connected to it. Just two wires on the back of the generator. One leads back to the F terminal on the Regulator Box and the other leads back to the D terminal. Again there is only one wire on the F Terminal not 2.

So if I read this correctly, I should Pull the F Wire and touch it for the F terminal. Should I pull the D Terminal Wire before I do that? I'm confused. Radius Arm work is done I need to get out and drive but I don't want to run out of electrons if Generator is not charging. The day is beautiful for LBC Top Down Driving HELP

 
This seems like the correct procedure to follow to make sure it is positive ground

If any of these events occurred, do not start the engine until polarization is done. The
polarity of the generator must be set to match that of the voltage regulator.
Make a jumper wire (14 or 16 gauge) long enough to reach from the battery to the
generator. Put alligator clips on both ends.
To polarize a generator on a tractor having a Delco 6V positive ground system or a Lucas
6V or 12V positive ground system, attach one clip to the A terminal on the generator. With
the other clip, briefly for only a split-second (or a spark occurs) tap the negative ( - )
terminal on the battery.

Not this one below
To polarize a generator on a tractor having a Delco 12V negative ground system, attach
one clip to the A terminal on the generator. With the other clip, briefly for only a split-second
(or a spark occurs) tap the positive ( + ) terminal on the battery.
Turn
 
Never Mind - Found a MOSS and John Twist Video. Touch the A and F together momentarily and that should fix.
 
Never Mind - Found a MOSS and John Twist Video. Touch the A and F together momentarily and that should fix.
 
OK so Touching between A & F did not do it. Fairly weak spark and lots for Green on those Terminals. Next step will be to Clean all of the Green off and see if something will result from Cleaning. I could not initially get a spark by touching between until I pressed really hard with screwdriver. So if that doesn't work next ideas gentlemen.
 
If that much corrosion on the terminals then you may just not be getting good contact with the wires, same as the green stuff on the battery terminals prevents it from taking the charge.
 
I'm not sure that procedure is right. Unless the engine is running, the generator output wire should have no voltage on it.

To polarize, I'd disconnect the field wire and run a wire from the battery ungrounded terminal (negative if you are positive ground) to the field terminal. Keep it connected a few seconds. You should get sparks, but the sparks don't do anything; the current while the thing is connected is what polarizes it.

That said, the importance of polarizing the generator is way overstated. It will probably start working even if you don't go through the polarization procedure. Maybe just not right away.

I'd clean up all the connections, check the generator brushes, and try again. If no luck, check the field-coil resistance, with a multimeter. It should be a few ohms; I don't remember exactly (probably 4-6 ohms). In any case, if it's far from that value, something is wrong. Another good test is to disconnect the generator wiring and connect the output to the field terminal. Measure the voltage as you run the engine--you should easily get about 20V at models engine speed. Don't run the engine too fast, or you will get a voltage high enough to cause some damage.

If all that checks out, the regulator may be the culprit. There are standard regulator tests listed in the shop manual. Try those before buying a new unit.
 
I'm pretty sure polarizing the brushes is only necessary after having changed the brushes. Steve said it right; start at the generator and work back. with a 50 year old car anything is possible...brushes, connections, corrosion, voltage regulator....
 
Will have time to trouble shoot tomorrow night. If Generator or Voltage Regulator are T.U. an alternator will happen quickly. Hopefully something simple. Hate to lose the tach drive but will be switching to Negative Ground and an alternator for the new engine that is coming.
 
View attachment 45414View attachment 45412Culprit was a broken brush spring. New Springs and Brushes cleaning, and they even touched up the paint on the generator. In and out of the shop in 2 days and $95 later I installed tonight. Started right up and makes no unknown noises a good thing. Generator Lamp still glowing brightly. I turned off the engine and touched the A and F Terminal on the Voltage Regulator together and got a few good sparks. Started Engine up and Generator Lamp now glowing faintly, let the engine warm up for a few minutes and Generator lamp was still glowing. Let the engine return to idle and lamp went out. Checked voltage at the battery while engine at idle 14+ Volt just like it is supposed to be. Engine compartment looking pretty nice right now but a change is a coming.

Bumper delete option on Bugsy has now been accomplished. After breaking each and every bumper bolt off on Bugsy II trying to remove in preparation for a front tilt I was pleasantly surprised when a 9/16" wrench loosened all four bolts and the bumper has moved into the basement. I'm tired of trying to get the bonnet up and down with the bumper in the way. Front tilt may happen very soon.

Also there is a new visitor that took up permanent residence in the garage with Bugsy this week. Wonder what it could be. Hmmm an expensive early Christmas Present. I don't think I can get it upstairs to put under the tree but perhaps a bright red bow. Santa, I promise I haven't yet peeked. So much better looking without a front bumper. Tomorrow will be my first real opportunity to drive and evaluate Bugsy without worrying about Rear Suspension Clunks and running out of Electrons in the Battery. A good romp will be in order this weekend. 55 tomorrow but 68 and sunny on Sunday. Time to put the hubcaps back on as well.

View attachment 45415
 
Grille sprayed with Chrome Paint looks presentable but a brand New AH Spare Triple Chromed Grill awaits after painting. Side Mirrors need to be installed as well. This 948 with Cooper S Head and HS-2's and a LCB Header is lively and revs unbelievably well. But a change is a coming...3.9 Pumpkin is coming from NC and Gerard's 5-Speed Kit is going to get put to good use as well. New Shocks and Springs and Front Discs and Wishbones and Bushings are the start as soon as it get's too cold to go romping. Front end seems low and springs definitely have more bounce than they should. Rear may have been lowered as well as I can't get the floor jack to slide under the gas tank. Rotator Cuff Surgery on Wednesday that will slow down progress for a little while. Bugsy gets driven tomorrow and I get to do a full fledged extended evaluation.
 
Jim,
Great progress and get everything done that you can before Wednesday since you'll be immobilized for a while!
Rut
 
I am Totally Chuffed!!! Bugsy had his first real time out and about today enjoying a beautiful fall day. First a trip to Tim Bosse's house early this am where he pronounced my drum brakes about as good as they get. Enjoy look at his new garage under construction that can hold 4 LBC'S. Back home,hubcaps go on and get ready to take grandsons and my son for a ride. Austin, age 10 pronounced windingbout to 6k in second gear, screaming "This is totally AWESOME!". We blasted down country roads, leaves falling, sunny and 68 degrees. Back home 8 year old Aric had the same reaction, "This is so cool!!!!" Over and over. Bugsy really winds up and is loud above 4K. But sounds awesome. My son timidly took the wheel and tirtured the tranny trying to shift into 3rd but we survived. Then a run to my friend Jeri's house where she presented me with 19" Chrome bucket shaped Harley Sportster muffler the she found this morning at a motorcycle swap meet. $15 yeah. It's perfect for Bugsy and will quiet his obnoxious tone.

Jeri then told me I'm going to show you my favorite roads to bkast down on my Norton. I was then directed down some absolutely fantastic roads not far from me, tree covered lanes and twisty turny roads perfect to check out Bugsy. It was fabulous almost a hour of blasting down these lanes. Bugsy took it all in stride. Engine revs and Rex's, temps rock solid about 175 as I flogged him pretty hard. No not perfect, squeal from left wheel that I think is brake shoe rubbing against drum. Stops when I change directions one way and then cones back when I go the other way.

Brakes I hate them. A few weeks and there will be discs on the front and upgraded backing plates in the rear. Shocks really soft tube shocks bottom out in the rear on hard bumps and seat foams definitely need upgrading. Tube shocks will go over the Winter along with a 3.9 diff. All stuff that will be fixed over tine.

But for the first trip out and about, probably 50 miles on the odometer today, it was a fabulous day. I remain totally Chuffed! Thanks Bugsy for a great day��
 
Jim,
All I can say is 'Woohoo!!!'!
Rut
 
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