Farm Equipment - WD 45 coil grounding?

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WD 45 coil grounding?

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Topic: WD 45 coil grounding?

Posted By: Ken McGregor
Subject: WD 45 coil grounding?
Date Posted: 10 Aug 2016 at 9:05am

I recently read something about a WD45 having power losses when opened-up but would idle not too bad. There were a couple of postings advising an inspection of the coil grounding. I need more information on this. Is it just the clamp-around holder that fastens into the distributor housing or what exactly are we talking about here. I only have the one wire (6V) to the coil and the high test wire coming out of course.
Just showing my ignorance but someone has to ask;>((

regards,
Ken McGregor

Replies:

Posted By: CAL(KS)
Date Posted: 10 Aug 2016 at 9:23am

the circuit is completed through the points whether positive or negative with the feed wire on the other side of the coil. maby they were referring to the coil grounding internally, and to check with a ohm meter

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Me -C,U,UC,WC,WD45,190XT,TL-12,145T,HD6G,HD16,HD20

Dad- WD, D17D, D19D, RT100A, 7020, 7080,7580, 2-8550's, 2-S77, HD15

Posted By: DougS
Date Posted: 10 Aug 2016 at 9:28am

No, the other end of the high voltage circuit is grounded through the coil case. That's different from the primary (points) circuit. Check the case of the coil and ensure that it has a low resistence to the engine block.

Posted By: Brian Jasper co. Ia
Date Posted: 10 Aug 2016 at 10:09am

DougS wrote:

No, the other end of the high voltage circuit is grounded through the coil case. That's different from the primary (points) circuit. Check the case of the coil and ensure that it has a low resistence to the engine block.

No, that's not how it works. There was discussion on the Facebook A-C page. I posted some pics from a text book I saved from when I went to trade school. The coil secondary and primary negative terminals are tied together. The coil case is insulated from the windings. There is one exception to this which is GM HEI with the coil in cap systems. In 74 when it was first offered, the coil secondary was tied to the negative. In 76 they were changed to a separate ground.

Otherwise the only time when you see a coil grounded is because there is a condenser or radio noise suppressor attached to the coil bracket.

You can take the coil loose while the engine is running (not GM HEI) and it will not bite you.

If you do facebook, find my page Brian Watson. I put a few pics of the old text book that was compiled by Sun Electric.

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"Any man who thinks he can be happy and prosperous by letting the government take care of him better take a closer look at the American Indian." Henry Ford

Posted By: DougS
Date Posted: 10 Aug 2016 at 10:30am

Then kindly point out the high voltage (spark) return path to me when the points are open, as they are when the plug fires.

Posted By: Brian Jasper co. Ia
Date Posted: 10 Aug 2016 at 10:32am

Through the condenser.

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"Any man who thinks he can be happy and prosperous by letting the government take care of him better take a closer look at the American Indian." Henry Ford

Posted By: Brian Jasper co. Ia
Date Posted: 10 Aug 2016 at 10:36am

Remember, the condenser does two jobs. It reduces arcing at the points. It also assists in charging the coil primary.

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"Any man who thinks he can be happy and prosperous by letting the government take care of him better take a closer look at the American Indian." Henry Ford

Posted By: Brian Jasper co. Ia
Date Posted: 10 Aug 2016 at 1:47pm

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"Any man who thinks he can be happy and prosperous by letting the government take care of him better take a closer look at the American Indian." Henry Ford

Posted By: Brian Jasper co. Ia
Date Posted: 10 Aug 2016 at 1:50pm

The preceding pics come from Sun Electric Electronic Ignition Diagnosis and Testing 1985 Edition.

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"Any man who thinks he can be happy and prosperous by letting the government take care of him better take a closer look at the American Indian." Henry Ford