Create your own blog: viewtopic.php?f=7&t=17487

Regulator failure

Electrical issues
Forum rules
Please do not start new topics here, but here: New Panhead and Flathead topics
Post Reply
1950Panhead
Posts: 1586
Joined: Wed Jul 07, 2010 4:28 am
Bikes: 1950Panhead
Location: USA

Regulator failure

#1

Post by 1950Panhead » Sun Sep 18, 2011 2:07 am

My regulator died today. The moving arm was floating between the top and bottom points, sometimes touching the bottom points. Has anyone experienced this before?

The story:
Went to start my panhead this morning and the battery was dead. Charged battery for 15 minutes, bike started, went to Harley dealer for free lunch today. Went to leave dealer and battery was dead again. Charged battery at dealer for 15 minutes, went dead before I could get the bike started. Went to parts department and asked if they had a 6 volt battery. They did, amazing! Bought battery. Installed battery and got sparks when connecting terminals. High tailed it for home and made it. Ran tests, regulator had failed.



john HD
Moderator
Posts: 3674
Joined: Sat Aug 20, 2005 7:24 pm
Bikes: '42 WLA X 2, '55FL, '93 Ultra Classic, '91 Fatboy, '97 883, '71 Suzuki Duster 125, '83 GPz 750.

Re: Regulator failure

#2

Post by john HD » Sun Sep 18, 2011 2:33 am

what type of regulator?

if it is one of the delco units look on the back and see if the ground wire is still attached. it is a little jumper between the case and the mount.

john

FlatHeadSix
Moderator
Posts: 2681
Joined: Sun Jun 06, 2004 5:14 pm
Bikes: '31 VL, '34 VD, '45 WLA, '47 WL, '49 FL, '51 WL, '58 ST (Hummer), '71 GE (Servi)
Location: Lonoke, Arkansas

Re: Regulator failure

#3

Post by FlatHeadSix » Sun Sep 18, 2011 4:19 am

the first question should be: what kind of generator is on the bike? Is it a 3-brush or a 2-brush, 6 volt or 12 volt?

The most common installation on an OEM 1950 Pan is a 3-brush with a Relay, a Police bike would have a 2-brush with a regulator. The old mechanical regulators had a relay circuit as well as a field circuit, the relay in the regulator served exactly the same purpose as the relay used on the 3-brush systems; it should disconnect the battery from the generator when the bike is shut off. If the relay does not open and disconnect the generator from the battery when you shut the bike off it will discharge the battery, in a hurry.

We need a little more info, what type of charging system have you got on the bike?

mike

1950Panhead
Posts: 1586
Joined: Wed Jul 07, 2010 4:28 am
Bikes: 1950Panhead
Location: USA

Re: Regulator failure

#4

Post by 1950Panhead » Sun Sep 18, 2011 1:02 pm

If the relay does not open and disconnect the generator from the battery when you shut the bike off it will discharge the battery, in a hurry.
No kidding.

Original 3 brush generator, Delco relay, there is a jumper wire soldered on the bottom frame that goes to the lower contact on the upper contact pair.
You do not have the required permissions to view the files attached to this post.

FlatHeadSix
Moderator
Posts: 2681
Joined: Sun Jun 06, 2004 5:14 pm
Bikes: '31 VL, '34 VD, '45 WLA, '47 WL, '49 FL, '51 WL, '58 ST (Hummer), '71 GE (Servi)
Location: Lonoke, Arkansas

Re: Regulator failure

#5

Post by FlatHeadSix » Sun Sep 18, 2011 2:08 pm

50Pan,
What you have is the original equipment for a 3-brush system. The 32E 3-brush generators did not have an external regulator, the 3rd brush inside the generator is what regulates it. It is a common error to call the external unit a regulator, it is, in fact, only a cut-out relay.

There are 2 sets of points in the relay, the upper set is normally closed when the bike is not running, this is the set that makes the "GEN" light come on when you switch on the ignition. The lower set is what connects the generator output to the battery, this set should be open when the bike is shut off. The lower set of points should not close until the generator begins to produce electricity, output from the generator energizes the magnetic coil and pulls the arm down, it opens the upper set of points so the "GEN" light goes off and closes the lower set so the electricity will flow to the battery and charge it.

so, if your relay will not "open" when you switch off the iginition it could be one of 3 things:
1. Bad Relay
2. A short in the wiring which is feeding voltage to the wrong side of the Relay and causing it to energize and close
3. An internal short in the generator which is feeding voltage to the relay when the bike is shut off.

You should be able to determine where the problem is using a good volt meter, remember to disconnect the components so they are isolated from each other when testing.

mike

1950Panhead
Posts: 1586
Joined: Wed Jul 07, 2010 4:28 am
Bikes: 1950Panhead
Location: USA

Re: Regulator failure

#6

Post by 1950Panhead » Sun Sep 18, 2011 4:32 pm

Mike,
Thanks for responding to my post. The relay has failed, the upper points should contact when off and they don't. I could bend the arm to cause the upper points to contact again, however I am interested in what caused the relay to fail. I installed a spare relay and everything is ok.

If I understand your post the regulator disconnects the battery and generator when the battery is fully charged in the two brush system.

How does the third brush do this in the three brush generator?
Jerry

FlatHeadSix
Moderator
Posts: 2681
Joined: Sun Jun 06, 2004 5:14 pm
Bikes: '31 VL, '34 VD, '45 WLA, '47 WL, '49 FL, '51 WL, '58 ST (Hummer), '71 GE (Servi)
Location: Lonoke, Arkansas

Re: Regulator failure

#7

Post by FlatHeadSix » Sun Sep 18, 2011 5:59 pm

Jerry,
The 3-brush generators are constant output, sort of, they always produce electricity when they are turning. They have 2 field coils, one is connected through the third brush, the other receives current when the lights are switched on. The 3rd brush does not actually regulate in the true sense, it merely presets the generator for whatever constant output you reguire, the idea is to match the output to the load. The other unique part of the design of the 3-brush units is that the output decreases as rpm increases, this is what keeps it from boiling the battery dry on long trips at highway speeds. Not perfect but they worked just fine, after all they only used them for over 20 years without any changes or modifications.

The regulator on a 2-brush system does not open the cut-out relay when the battery is fully charged, it stays closed as long as the engine is running. Regulation of generator output is accomplished by increasing or decreasing the current to the field coils.

glad you found, and fixed, your problem!

mike

Post Reply

Return to “Electrical”