The Ford Barn

Tom Wesenberg · 05-11-2012, 08:06 AM

Last weekend I found out that the replacement field coils come with wires long enough to install the coils on the wrong side of the case. I tested a friend's newly rebuilt generator last Saturday and when I polarized it, it spun backwards.

Good fields should draw about 3 1/2 to 4 1/2 amps. You can check the field windings while the generator is on the car by lifting the adjustable brush off the commutator, or placing a piece of paper or cardboard between the brush and commutator. Test with at least a 4 amp charger as pictured and set to 6 volts and the POSITIVE cable on the field ground.

With the output stud facing away from you, as in the picture, the compass needle (NORTH) should face left. It will face left whether you place the compass on the left side of the case, in the center, or on the right side of the case.

Notice that this is the later gnerator with the output stud near the rear, and the field ground is clamped to the case by the insulating washer on the output stud.

caserider · 05-11-2012, 02:00 PM

Thanks for another informative post with clear supporting images.
Jason

BudP · 05-11-2012, 07:38 PM

Tom,
Someday I hope to see your comments, instructions and observations along with your photographs gathered into a manual. I, and undoubtedly many others, have acquired an understanding of automotive electronics that we never had!
Bud

d.j. moordigian · 05-11-2012, 07:48 PM

............................." Tom's Tutorials ".........................................

Put all your electric stuff on the "sticky" at the top of the page, so we can find
in one spot...................Pluck?

ctlikon0712 · 05-11-2012, 08:01 PM

D.J. Moorrdigian that is a great idea, probably allot of work but I'd like to see it!

dr.j · 05-12-2012, 05:56 AM

Sponsored Links (Register now to hide all advertisements)

Tom, I wish I lived closer to your workshop; I am sure not a day would pass by that I wouldn't learn something new.

Tom Wesenberg · 05-12-2012, 06:23 AM

Quote:

Originally Posted by dr.j

Tom, I wish I lived closer to your workshop; I am sure not a day would pass by that I wouldn't learn something new.

Thanks Dave, and I wish I had a good workshop. I'm just working out of my basement and small garage.

1930artdeco · 05-12-2012, 10:26 AM

Tom,

Is there a left and right field coild? I just bought new coils and installed them in my gen. I installed them with the wires facing the rear. I am not at home now and trying to remember how I Installed them and panicking since I have had them tightened down already.

Mike

Tom Wesenberg · 05-12-2012, 11:18 PM

Quote:

Originally Posted by 1930artdeco

Tom,

Is there a left and right field coild? I just bought new coils and installed them in my gen. I installed them with the wires facing the rear. I am not at home now and trying to remember how I Installed them and panicking since I have had them tightened down already.

Mike

Yes, the coils are different, so just do a check as I posted above to be sure they are installed correctly.

Tom Wesenberg · 06-05-2012, 09:47 AM

The mystery has been solved. My friend gave me the generator that mtors backwards and I took it apart the other day. He replaced the field coils to the correct side as I suggested, but the wrong field wire was being grounded, thus reversing the field polarity. This picture shows the RED wire going to ground, but it should lead to the adjustable brush. Since this generator case is badly rust pitted this will be used for good parts to fix other generators.

05-11-2012, 08:06 AM	#1
Tom Wesenberg Senior Member Join Date: May 2010 Location: Mpls, MN Posts: 27,582	Installing and Testing Generator Fields Last weekend I found out that the replacement field coils come with wires long enough to install the coils on the wrong side of the case. I tested a friend's newly rebuilt generator last Saturday and when I polarized it, it spun backwards. Good fields should draw about 3 1/2 to 4 1/2 amps. You can check the field windings while the generator is on the car by lifting the adjustable brush off the commutator, or placing a piece of paper or cardboard between the brush and commutator. Test with at least a 4 amp charger as pictured and set to 6 volts and the POSITIVE cable on the field ground. With the output stud facing away from you, as in the picture, the compass needle (NORTH) should face left. It will face left whether you place the compass on the left side of the case, in the center, or on the right side of the case. Notice that this is the later gnerator with the output stud near the rear, and the field ground is clamped to the case by the insulating washer on the output stud. Last edited by Tom Wesenberg; 05-11-2012 at 08:21 AM.

05-11-2012, 02:00 PM	#2
caserider Junior Member Join Date: Jan 2012 Posts: 27	Re: Installing and Testing Generator Fields Thanks for another informative post with clear supporting images. Jason

05-11-2012, 07:38 PM	#3
BudP Senior Member Join Date: Jun 2011 Location: Oakton, VA Posts: 437	Re: Installing and Testing Generator Fields Tom, Someday I hope to see your comments, instructions and observations along with your photographs gathered into a manual. I, and undoubtedly many others, have acquired an understanding of automotive electronics that we never had! Bud

05-11-2012, 07:48 PM	#4
d.j. moordigian Senior Member Join Date: May 2010 Location: Fresno, Ca. Posts: 3,636	Re: Installing and Testing Generator Fields ............................." Tom's Tutorials "......................................... Put all your electric stuff on the "sticky" at the top of the page, so we can find in one spot...................Pluck?

05-11-2012, 08:01 PM	#5
ctlikon0712 Senior Member Join Date: Feb 2011 Location: Cocoa, Florida Posts: 1,609	Re: Installing and Testing Generator Fields D.J. Moorrdigian that is a great idea, probably allot of work but I'd like to see it! __________________ Wanted: Simmons Super Power Head Craig Likon 1931 150B

05-12-2012, 05:56 AM	#6
dr.j Senior Member Join Date: May 2010 Location: Portland, ON, Canada Posts: 315	Re: Installing and Testing Generator Fields Sponsored Links (Register now to hide all advertisements) Tom, I wish I lived closer to your workshop; I am sure not a day would pass by that I wouldn't learn something new. __________________ Dave A Jamieson Portland, ON Canada 1928 Tudor

05-12-2012, 10:26 AM	#8
1930artdeco Senior Member Join Date: May 2010 Location: Lynden, Wa Posts: 3,550	Re: Installing and Testing Generator Fields Tom, Is there a left and right field coild? I just bought new coils and installed them in my gen. I installed them with the wires facing the rear. I am not at home now and trying to remember how I Installed them and panicking since I have had them tightened down already. Mike __________________ 1930 TownSedan (Briggs) 1957 Country Sedan

06-05-2012, 09:47 AM	#10
Tom Wesenberg Senior Member Join Date: May 2010 Location: Mpls, MN Posts: 27,582	Re: Installing and Testing Generator Fields The mystery has been solved. My friend gave me the generator that mtors backwards and I took it apart the other day. He replaced the field coils to the correct side as I suggested, but the wrong field wire was being grounded, thus reversing the field polarity. This picture shows the RED wire going to ground, but it should lead to the adjustable brush. Since this generator case is badly rust pitted this will be used for good parts to fix other generators.