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#1 chieffan ONLINE  

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Posted January 13, 2015 - 04:53 PM

Working on a BR6 Briggs motor on a Gardener.  There is no spark plug wire attached to the coil.  Looks like the solder came off.  Is there a way to meter these coils out to make sure they are good before I get to deep into the ignition system?  Every thing is nice and clean behind the flywheel but I haven't checked the points yet.  Maybe tomorrow.  Would like to check the coil first to be sure it is good.  Thanks for the help.


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#2 classic ONLINE  

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Posted January 13, 2015 - 05:49 PM

Your best bet is to remove the points then remove the points plunger. These points plungers can swell with age and cause spark problems. Make sure the plunger moves freely then clean the points and set the point gap. Install a new coil wire, install the flywheel with the flywheel nut only hand tight. Ground your spark plug on the engine and turn the flywheel by hand. If that doesn't do it, try another spark plug then move on to replacing the condenser. These coils don't usually fail. I actually thought I had a bad coil and it turned out to be corrosion where the small coil wire is crimped into the loop connector. It's wise to make sure all of the above things above are in check while you have it apart anyway. One other thing you should check is crankshaft up and down play. If the crank bushings are worn, your flywheel may be shorting out on the flywheel..and never clean a flywheel with a wire brush or steel wool.

Edited by classic, January 13, 2015 - 06:14 PM.

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#3 DougT ONLINE  

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Posted January 13, 2015 - 06:28 PM

You should get somewhere around 5K ohms on the secondary to ground and about 1-2 ohms on the primary side. Briggs recommended not to solder the plug wire to the coil. Make sure the coil mounting is clean and making good ground to the block. I like to see a spark jump at least 5 times the plug gap outside the cylinder to make sure it will fire under compression.


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#4 chieffan ONLINE  

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Posted January 13, 2015 - 07:27 PM

I didn't know that Briggs didn't recommend soldering the plug wire to the terminal.  That is why it is so clean looking.  Will dig into it deeper tomorrow.  Need to clean the carb good, change the oil in the engine and the gear reduction case before it is ready to try anyway.  Thanks much for the information.  We live and learn, when we stop learning  we probably have stopped living.


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#5 superaben OFFLINE  

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Posted January 13, 2015 - 08:56 PM

Just an FYI, if it comes down to where you are looking at what might be a bad coil, I have an old coil tester here that can give you a verdict.  It is a special magneto coil tester. 

 

Ben W.


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#6 Bruce Dorsi ONLINE  

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Posted January 13, 2015 - 09:18 PM

I have an old coil tester here that can give you a verdict.  It is a special magneto coil tester. 

 

Ben W.

 

What is your tester like, Ben?  ....Brand?  .....Pics? 

 

Thanks!


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#7 superaben OFFLINE  

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Posted January 13, 2015 - 11:48 PM

What is your tester like, Ben?  ....Brand?  .....Pics? 

 

Thanks!

 

Its a long story.  I love my coil testers, and I they sweat out here since I work through quite a few tractor magnetos. 

 

My most recent tester is a Graham Lee model 51-RP.  I bought it actually about two months ago to replace an old ratty Merc-o-Matic that had just about given up the ghost.  The Merc had worked its life away for someone else before I got it.  I never trusted it, even with fresh tubes it still gave strange readings sometimes.  It was also never the same after something inside shorted out.  :mad2:  I sold it to another magneto guy who wanted to use it with another one to combine for a nice unit. 

 

The Graham Lee is the best you can get from my understanding.  It better be for what I paid for it!  It hadn't been used much, and was clean as a whistle.  Even the plastic gauge cover was clear and not yellowed and brittle.  I did the calibration test on it, and with fresh tubes it passed with flying colors. 

 

The 51-RP can test coils (stress test and simple test) measure condenser capacity in microfarads, check resistence, and also check your points.

 

Ben W.


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#8 superaben OFFLINE  

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Posted January 13, 2015 - 11:49 PM

I need to get a studio portrait of my tester.  I'll do that so you can see what it looks like. 

 

Ben W.


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#9 Bruce Dorsi ONLINE  

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Posted January 14, 2015 - 12:26 PM

Thanks, Ben!

 

I found some pics of that tester at e-bay.  ...One sold for $400+ with no guarantee of condition.

 

http://www.ebay.com/...57#ht_168wt_900

 

I've got a Merc-O-Tronic unit that needs repair.  ....Estimates are $250-$300 to get it repaired. 


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#10 superaben OFFLINE  

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Posted January 14, 2015 - 06:37 PM

Thanks, Ben!

 

I found some pics of that tester at e-bay.  ...One sold for $400+ with no guarantee of condition.

 

http://www.ebay.com/...57#ht_168wt_900

 

I've got a Merc-O-Tronic unit that needs repair.  ....Estimates are $250-$300 to get it repaired. 

 

That looks identical to my tester.  I suppose someone might have bought it and then resold it to me, except when it came to me it was known to be working.

 

What's wrong with your Merc?

 

Ben W.


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#11 Bruce Dorsi ONLINE  

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Posted January 15, 2015 - 05:53 PM

 

What's wrong with your Merc?

 

Ben W.

 

It doesn't work!  :smilewink:

 

According to the company, it can be repaired, tested, & re-calibrated for approx. $250-$300.  ... I was told the vibrator is a common failure point, but that is no longer available, if that is what failed. 

 

My neighbor is a retired electrical engineer, and he has offered to try to repair it for me.  ...I'm going to take him up on his offer. 


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#12 chieffan ONLINE  

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Posted January 16, 2015 - 09:35 AM

Thanks for the info.  My coil tested out OK.  Found out the plug that came with the machine, looked like new was the wrong plug and bad.  Put an old chain saw plug on and it had nice blue spark.  Problem solved. now on to the next one.


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