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Old 06-05-2012, 10:13 PM   #1
Des
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Default points burning out on the Model A distributer

How do I stop contact points burning out on the Model A distributer?
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Old 06-05-2012, 11:58 PM   #2
Peter J
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Default Re: points burning out on the Model A distributer

Des,
Swap out your condenser, that could be it.
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Old 06-06-2012, 02:38 AM   #3
dave in australia
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Default Re: points burning out on the Model A distributer

Do you have the right coil. Some coils require a ballast resistor to prevent the points from frying, that is if you have gone away from an original six volt coil.
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Old 06-06-2012, 02:40 AM   #4
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Default Re: points burning out on the Model A distributer

My points were burning blue within minutes.

Turned out to be the powerhouse overcharging.
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Old 06-06-2012, 02:24 PM   #5
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Default Re: points burning out on the Model A distributer

Without a condenser operating properly, points will not last but a few minutes.
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Old 06-06-2012, 03:31 PM   #6
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Default Re: points burning out on the Model A distributer

ditto condensor
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Old 06-06-2012, 06:44 PM   #7
Purdy Swoft
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Default Re: points burning out on the Model A distributer

A bad or loose connection at the battery cable will cause a voltage spike and burn out the points , I've had it happen .
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Old 09-16-2019, 06:06 AM   #8
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Default Re: points burning out on the Model A distributer

My points are lasting a coupe hundred miles, before they burn out. B distributor with a 6V system charging at 7 amps, I run parking lights while driving. I have 1.5 ohm resistor on incoming side.

Since I added the resistor it takes longer for the points to burn out. I also burn out brake lights unexpectedly.

I have checked all the connections from the starter through the ignition switch and amp meter to the distributor. I haven't checked the positive ground from the frame to the battery yet. But if that was loose, why would it turn over?

I run the diode for my cutout.
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Old 09-16-2019, 09:00 AM   #9
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Default Re: points burning out on the Model A distributer

The whole purpose of the condenser is to act as a buffer for the counter emf of the coil, and protect the points from arcing and burning. As the points open, the surge of current needs a place to go, and the condenser absorbs this charge. Therefore, the value of the condenser needs to match the coils output pretty close. If the condenser is weak, or if the coil is not correct, the life of the points is negatively affected.

Condensers do go bad a lot more often than coils, so start there .
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Old 09-16-2019, 09:11 AM   #10
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Default Re: points burning out on the Model A distributer

Quote:
Originally Posted by Corley View Post
The whole purpose of the condenser is to act as a buffer for the counter emf of the coil, and protect the points from arcing and burning. As the points open, the surge of current needs a place to go, and the condenser absorbs this charge. Therefore, the value of the condenser needs to match the coils output pretty close. If the condenser is weak, or if the coil is not correct, the life of the points is negatively affected.

Condensers do go bad a lot more often than coils, so start there .
Ok, I'll give that a shot.
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Old 09-16-2019, 09:32 AM   #11
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Default Re: points burning out on the Model A distributer

Burning out brake lights would make me think a poor battery connection causing the generator voltage to spike like Purdy said back in 2012.



Have you burned out any more bulbs since going through your wiring? I would definitely check out your battery ground.
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Old 09-16-2019, 09:39 AM   #12
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Default Re: points burning out on the Model A distributer

Quote:
Originally Posted by Des View Post
How do I stop contact points burning out on the Model A distributer?
how long do they last before they're pitted/burnt out? Some of the "modern" type points in particular are poor quality and seem to last only 2000 miles or so whatever.
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Old 09-16-2019, 11:00 AM   #13
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Default Re: points burning out on the Model A distributer

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Originally Posted by johnbuckley View Post
how long do they last before they're pitted/burnt out? Some of the "modern" type points in particular are poor quality and seem to last only 2000 miles or so whatever.
John, my points are lasting about 200 miles. I'm using NOS model B point sets.

I will try a condenser, and look at my ground connection as Ryan suggests.

The only reason I didn't consider the ground was because it starts easily. Wouldn't it turn over slow if I had a poor ground?
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Old 09-16-2019, 11:51 AM   #14
Purdy Swoft
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Default Re: points burning out on the Model A distributer

Sometimes a slightly loose ground connection will make good enough connection to work , other times it may not .
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Old 09-16-2019, 12:09 PM   #15
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Default Re: points burning out on the Model A distributer

Not much info to work with.
6v or 12v ? If 12v then look at the coil, make sure its a 3ohm or has a ballast resistor.
There shouldn't be more than 8v to the points.

A loose connection can cause the generator 'runaway' and put out about 30v.

As the others said, good info.
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Old 09-16-2019, 12:16 PM   #16
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Default Re: points burning out on the Model A distributer

These threads get so confusing we people hijack 7 year old threads. Need to start a new thread.
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Old 09-16-2019, 03:00 PM   #17
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Default Re: points burning out on the Model A distributer

Quote:
Originally Posted by Bob C View Post
These threads get so confusing we people hijack 7 year old threads. Need to start a new thread.
Yes I see, I was trying to do the opposite and not create a new thread with the same subject.
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Old 09-16-2019, 05:20 PM   #18
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Default Re: points burning out on the Model A distributer

I like what you did, shows you have already taken the initiative and done some research.


Let us know what you find using all of the info in this thread, new and old info.
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Old 09-17-2019, 06:41 AM   #19
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Default Re: points burning out on the Model A distributer

Oopps, I missed the date.
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Old 09-17-2019, 02:12 PM   #20
Bob Bidonde
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Default Re: points burning out on the Model A distributer

My best guess is that the points and or condenser case do not have a low resistance ground path back to the battery. Resistance should be 5 Ohms or less. I use jumpers to get the ground path resistance to 2 Ohms or less.
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File Type: jpg Ground Resistance Check.jpg (17.1 KB, 25 views)
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