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donmoore1904

Converting points to electronic ignition - change of magnet polarity optional?

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donmoore1904

Hello all,

This forum was immensely helpful to me "back in the day".  I have a 10 hp Briggs 243431 cast cylinder, 7010 3-speed, and the people here guided me through overhauling the BGB and rear end, and tuning the motor.  I ran into an "old timer" fellow customer at the Simplicity dealer who gave me an important tip on installing my new coil properly (which I have now forgotten).  I put in new points and plunger, going the "old school" route.  The tractor has served me extremely well for 17 years and may outlive me.

A week ago, after the cleaning procedure (disassembly to clean out blockages of air flow), I had a very weak spark.  While investigating I came across the latest catch of owners switching from points to electronic ignition.  I found a YT video where the fellow pointed out that if you install the coil with electronic ignition *backwards" you can avoid sending your flywheel to Briggs to reverse the polarity of the magnets.  I believe my points were dirty (hadn't touched them in years :( ) and though the tractor runs the best it has in a few years, I went ahead and bought armature kit 398811.  This is a nice kit, and includes the shut off wire, extra connector if you need to shorten the HV wire, a quality potted armature, and a flywheel key

The last I saw reference to Briggs reversing polarity of flywheels was a year ago - I assume they still do.  My question is, is there a compelling reason to not do what some people are advocating today - simply install the opposite as designed?  The difference is the HV wire is a little closer to the motor, and the shut down wire connector is on the outboard side instead of between the HV wire and motor.  Also the HV wire takes off 180 degrees away.  Thank you for any advice - I don't understand why Briggs would want to be reversing polarity of 40+ year old flywheel magnets if it isn't needed. 

Edited by donmoore1904
altered title

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brokenwrench

i have a my dad's big ten AC with the same briggs engine you have.i had just replaced the oem points coil a few years ago i just installed a nova 2 module it was half the price of a set of points and condenser which were bad.i got a longer screw and bolted the nova to the top point cover bolt. i have the bluest spark i have ever seen. it starts up  faster and runs smoother than ever.

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landlord2110

I have same engine in my landlord 2110, put the nova ll points in, didnt touch flywheel, and runs beautifully. I was constantly cleaning points & haven't done nothing in years since putting electronic ignition in.

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donmoore1904

That module retains the current coil, which is why the polarity isn't an issue - it won't change.  The module is also discussed in the video I used, by Taryl.  (He covers multiple solutions - my new module is at about time 14:45)

I appreciate the replies, and it gives me a glimpse of what others are doing today (maybe a few days too late).  What I haven't seen yet is someone indicate the Briggs module can be used by simply installing it "backwards".  It has "Cylinder side" and "This side Out" printed on it, and the advice of at least Taryl is just reverse it to make it work.  This reminded me of the polarity reversal I had heard about several years ago.  The Briggs unit appears to be top quality, and I own it now so... my druthers are to go ahead and use it as suggested by word of mouth, and not send my flywheel anywhere - which I can't envision doing.  It would be nice to hear someone else went this route to know I'm not headed in the wrong direction, so to speak.

By the by, I saw a comment somewhere that these electronic ignition modules do not work to as low a voltage as points/condensor.  I don't know if that is true.  I do sometimes have a low battery - I've had the same one since the used one I got in it in 2001.

Edited by donmoore1904

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MikeES

The Briggs Magneto and Nova II do not use any voltage from the battery.  The battery is only for turning the starter.

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donmoore1904
32 minutes ago, MikeES said:

The Briggs Magneto and Nova II do not use any voltage from the battery.  The battery is only for turning the starter.

That's a good point.  Hadn't given it any thought and should have.

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Bill725

It is my understanding the NOVA electronic ignition module utilizes the existing magneto armature and just replaces the existing points and condenser. The B&S Magnetron magneto armature, P/N 398811, replaces both the existing armature, points and condenser. I have converted (2) B&S cast iron engines from points ignition to the Magnatron, a 10HP and a 16HP. I had the polarity of both flywheels changed. Like you stated, apparently you can get away with installing the armature backwards and do not have to repolarize the magnets on the flywheel. If you happen to do this, please let us know if it works and how it went.

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donmoore1904

OK folks - I'll check back at some point but as of the moment plan to give it a shot.  I'm getting a bit old for yanking my motor to experiment.  My guess is someone may chime in in the meantime saying they did it and it came out fine.  I can't see a reason it won't work.  A  concern is timing - my memory is that with points, there was a certain alignment of an arrow and/or ??? that was expected right when the points opened - this was a tip an old timer told me off the top of his head standing at the parts counter at the Simplicity stealer.  With electronic, how do you do the equivalent?  The one video I saw and descriptions I have read sound like the armature was moved "until it works" - which sounds pretty unscientific.  Not critical?

Edited by donmoore1904

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dhoadley

If you mean by "giving IT a shot" trying a Nova II module, its plug and go. I'm an electric idiot, but I made it work. Very simple installation instructions, and the hard part was attaching the 2 wires. They're identical, and they say "try it one way and if it doesn't work, switch them." sm00

Edited by dhoadley

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Bill725

B&S P/N 398811 Magnetron armature installation instructions state: mount armature, set gap between armature and flywheel to 0.010" and tighten mounting screws. Nothing about ignition timing. Just push the "EASY" button.

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donmoore1904

dHoadley - I don't have a choice of going to anther solution at this point - if you read back you will see that I have a new B&S magentron and this thread was to ask questions about installing "it".  The previous poster said "try it and see what happens" - which referred to my magnetron, not a module.

Maybe I am being hyper - as Bill just wrote and I saw on a Zippo video last night - "you don't time a B&S motor".  I recall from my coil replacement that the mounting bracket has an adjustment (flywheel has to come off to get to it), and it can either rotate or translate.  I don't know why that would be if timing is not needed.  The advice I was given 15 years ago about adjusting it so the points open at a certain spot my memory tells me worked.  Maybe it doesn't matter, but the guy with the big teeth (Tyrel) in his video says he adjusted that bracket when his motor didn't run right.  He shows it being scribed so that its original position is known.  Whether you would call that "timing" or not - I assumed it would be.  It will alter when the spark occurs.

To add to my confusion about one direction or another, in a different Zippo video I thought he spoke of a change at some point B&S made so that flipping the new magenetron is not necessary.  Yet in Tyrel's video, he uses the same part # I bought, and flips it opposite as intended.  

I guess at this point "just try it" is the best advice.  It will probably work first time.  You can see I was trying to figure out how it should be before diving in.

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Tom45

The Briggs service manual gives instructions for points type ignition for adjusting the coil mounting bracket to set the timing.  My local Briggs dealer says to install a Magnatron on this bracket with the bracket in the same location as was used for properly timed points.    He also says that because the timing trigger is not in the center of the Magnatron coil that flipping it will affect the timing.  On the Briggs website there is a help line you can call or email, however my recent use of it was not much help.  

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