Ignition coil problem...

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Moxie26
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Ignition coil problem...

Post by Moxie26 » Thu Dec 05, 2024 8:01 pm

.... What would cause the vibrator point to magnetically stick to the center post of the primary coil ?...... As was asked by a friend .


Poppie
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Re: Ignition coil problem...

Post by Poppie » Fri Dec 06, 2024 3:53 am

The coils were most probably running on battery full time and not on Magneto which causes the centre core to become a permanent magnet that hold down the vibrating point. ....n


Ron Patterson

Re: Ignition coil problem...

Post by Ron Patterson » Fri Dec 06, 2024 9:47 am

Did the circumstances you described in your original post involve a 1913-1917 metal top coil?
Ron Patterson


Topic author
Moxie26
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Re: Ignition coil problem...

Post by Moxie26 » Fri Dec 06, 2024 10:25 am

No, Ron... Regular wood top


Ron Patterson

Re: Ignition coil problem...

Post by Ron Patterson » Fri Dec 06, 2024 1:18 pm

I only know of a situation with metal top coils that do not have the correct insulating washers installed on the adjuster bolt that causes this problem.
Ron


michaelb2296
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Re: Ignition coil problem...

Post by michaelb2296 » Fri Dec 06, 2024 1:34 pm

What tests have you done on the coil outside the box?


Topic author
Moxie26
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Re: Ignition coil problem...

Post by Moxie26 » Fri Dec 06, 2024 2:16 pm

I was asked to recalibrate this coil, opened up the side panel and noticeably the capacitor /condenser was replaced and checks out fine, the secondary coils check out find it around 3,200 ohms and also the primary core checks out. ..... Physical contacts checked out with at least a 0.030" point gap, 0.010" cushion spring gap, and the top bridge was parallel with the top Wood surface of the coil box..... Placed in tester and proceeded. There was a little noise from the coil and then stopped because the vibrator spring was magnetically adhering to the primary post..... Went a step further and replaced the coil points with a brand new set, and unfortunately got the same results... I was told that this set of coils was rebuilt, didn't know by who, since he bought the vehicle and parts including these rebuilt coils from an estate. .......... Just to add to this, this coil was tested on a HCCT, ... and then tested on a ECCT. ..... Both gave the same results with the vibrator spring magnetically adhered to the center core......... The owner kept the four good recalibrated coils and the fifth coil with the problem was discarded by him.


michaelb2296
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Re: Ignition coil problem...

Post by michaelb2296 » Fri Dec 06, 2024 2:24 pm

only when current is applied? There is a short somewhere.
Check out pgs. 22-26 of Tinkerin Tips


Ron Patterson

Re: Ignition coil problem...

Post by Ron Patterson » Fri Dec 06, 2024 3:44 pm

If the offfending coil is available I would to get it sent to me so I could take a closer look?
Ron Patterson


TXGOAT2
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Re: Ignition coil problem...

Post by TXGOAT2 » Fri Dec 06, 2024 3:56 pm

If the vibrator pulls down and stays down when current is applied, there must be an electrical issue. (Shorted capacitor?) If the vibrator sticks to the core with no current applied, maybe the core is magnetized. If so, hooking the coil up to a 12 volt battery with the polarity reversed might demagnetize the core. Hold the vibrator down and hit the coil with a dozen or so short zaps of reverse polarity 12 volt battery juice. Don't leave the coil connected for more than a couple of seconds. It would be a good idea to ground the high tension button when doing this. FWIW, I've never heard of a coil core becoming magnetized to any significant degree when no current is available. Since the capacitor is connected across the points, a shorted capacitor would energize the coil continuously whenever primary current was applied.


michaelb2296
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Re: Ignition coil problem...

Post by michaelb2296 » Fri Dec 06, 2024 5:54 pm

Did you run the ECCT cap test with paper between the points? Did you try continuity test across the cap?

What is the uF value of the cap????


Topic author
Moxie26
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Re: Ignition coil problem...

Post by Moxie26 » Fri Dec 06, 2024 7:00 pm

Ron and Michael... The owner disposed that coil, and when coils were checked on the ECCT, those proper tests were followed exactly as in the instructions. I've been using the hand cranked coil tester for over 25 years, and the ECCT for the last 12 yrs.


Poppie
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Re: Ignition coil problem...

Post by Poppie » Mon Dec 16, 2024 7:14 pm

Robert,
At the expense for the cost of a modern ECCT DC coil tester, why did you change from using the Hcct coil tester that you used for years? Do you find the ecct more accurate and why?....n


Topic author
Moxie26
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Re: Ignition coil problem...

Post by Moxie26 » Mon Dec 16, 2024 8:20 pm

Poppie .... Oh okay, keeping money out of this, with the hand crank coil tester. You have to keep two things in mind using the coil tester. After you have physically set your coil points. .With the HCCT , the two things you have to follow is constant turning RPM and making a mental note of when the coil points start to spark. Is very difficult to have four coils set the same even though you may have matching 1.3 ohms settings on all four...... the ECCT with the written direction procedure, will give equal firing adjustment to all four coils even though there will be slight amperage draw plus or minus. !......... The result will be a smoother running engine with ECCT calibration...... And yes, in my humble opinion, the ECCT gives more accurate calibration results.

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RajoRacer
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Re: Ignition coil problem...

Post by RajoRacer » Mon Dec 16, 2024 9:40 pm

Thus the reason KR Wilson motorized theirs !


Dan Hatch
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Re: Ignition coil problem...

Post by Dan Hatch » Tue Dec 17, 2024 7:18 am

So, does that mean KRW made the first ECCT????
Curious minds want to know.


TXGOAT2
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Re: Ignition coil problem...

Post by TXGOAT2 » Tue Dec 17, 2024 11:00 am

MCCT, maybe?

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