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| | | | Joined: Nov 2011 Posts: 103 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2011 Posts: 103 | This topic is not new and I've polarized one before but this time it didn't work. I've forgotten, engine running or not?--- A flash BATT to ARM?
Ben | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | NOT running, you want to do it as soon as you connect the battery, flash GEN to BATT - should be called out in all the shop manuals
Bill | | | | | Joined: Nov 2011 Posts: 103 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2011 Posts: 103 | Tim-
My amp needle didn't move from center. What I did was drop the generator to replace the pulley. When I replaced the generator it didn't show any charging at all.
Bill- I have a 1950 "Motor" manual and a Chevrolet truck shop manual neither of which mentions polarizing a generator. My voltage regulater has "Batt"--"Arm"--"fld"
Thanks for the replies
Ben | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | the ARM terminal is GEN .... under the electrical section>generating system> polarizing, bottom right Bill | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 |
" . . . I have a 1950 "Motor" manual and a Chevrolet truck shop manual neither of which mentions polarizing a generator. . . "
Ben,
Did you look at the link in my earlier post: it also shows the instructions in the 1948-1951 Truck Shop Manual. Bill's link is to clearer instructions in the same manual.
| | | | | Joined: Nov 2011 Posts: 103 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2011 Posts: 103 | Tim,
That link went to starters. I'm working on a generator.
Still not generating after polarizing.?? | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 |
Look at the note at the top of that page.
| | | | | Joined: Feb 2004 Posts: 29,746 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,746 |
are the wires connected to the generator correctly? Reversing the Arm and Fld wires will keep it from charging, or polarizing properly.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: Nov 2011 Posts: 103 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2011 Posts: 103 | Jerry,
I'm certain it's wired the same as before. I may have fried something--I flashed every terminal on the voltage regulator with no noticeable change at the Battery gauge. | | | | | Joined: Feb 2004 Posts: 29,746 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,746 | What is the residual voltage output at the armature terminal of the generator? With all wires disconnected, a polarized generator should produce at least 1/2 volt DC. If you ground the Field terminal the voltage at the armature terminal should rise, and go very high if the RPM is increased. A generator that passes those two tests will charge the battery. Move on to checking wire continuity and regulator functions. It is difficult to damage a DC generator short of burning up wires with a dead short.
A good analog (not digital) voltmeter and ammeter are pretty essential to getting a good diagnosis of a generator-type charging system. Digital meters are just too sensitive and quick-responding to get good information from a vibrating-contact regulator.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: Nov 2011 Posts: 103 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2011 Posts: 103 | Jerry,
Thanks so much. I'll start with testing the generator and then get back to you.
Thanks again
Ben | | | | | Joined: Nov 2011 Posts: 103 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2011 Posts: 103 | Jerry,
I have a CE analog tester. When I connect to the "A" terminal on the generator and then to ground I get no reading. I grounded the field termimal on the generator housing and reved the engine and still not even a tick on the test gauge.
If I can find a generator at a local salvage yard how can I tell if it is 12 or 6 volt?--- They won't know.
Thanks
Ben | | | | | Joined: Feb 2004 Posts: 29,746 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,746 | If the metal ID tag is present on the generator, a 6 volt unit will be painted black. 12V generators have red labels. Was it charging OK before you worked on the pulley? If you want to take this discussion to PM or telephone, I might be able to walk you through a quick teardown and continuity check before you give up on the one you have.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: Nov 2011 Posts: 103 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2011 Posts: 103 | Jerry,
Thanks for responding. There are no metal tags.
The generator was charging sort of ok--by that I mean it kicked in after the engine was reved maybe around 800 - 900 rpms and as long as the engine stayed reved it charged ok. It would be great if we could talk by telephone.
Ben | | | | | Joined: Jun 2010 Posts: 1,001 Shop Shark | | Shop Shark Joined: Jun 2010 Posts: 1,001 | Definitely, the generator could be faulty and still sort of test ok. I once had a corvair with 12v generator that passed all my home tests...it even ran as a motor on the bench. Never could get it to charge the battery. Took it to the starter rebuild shop and they said the armature was bad. They rebuilt it (reverse thread on the armature was an issue that prolonged the process and caused me to have to wait for a replacement armature to be custom made) and all was well in the world. Without a growler, it might be difficult to fully home test the generator. | | |
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