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Magnetron for 10 Hp Cast Iron L head


Stickid

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I have the Briggs 10Hp out of my Landlord and while picking up gaskets the parts guy and I were talkng about ignition. He said I could just change out the points style and put in the magnetron.I bought the parts and am curious about something I read regarding the polarization of the magnets. Does something have to be done there or can I simply go ahead and install the magnetron ignition. I also bought the piece to replace the plunger so I can just take the points etc. right out. I have two of these engines so I can re use them there if I want. I don't want to mess anything up so I haven't proceeded beyond the reading stage yet.
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So I've been getting educated about this whole magnetron issue and have discovered that when I put a compass up to the flywheel magnet it points to N so this flywheel has not been re polarized(if I am understanding correctly). I'm okay with going with the points system but I bought a new armature last year and I read in one of the previous posts that if it says "this side out" that means it's a magnetron armature and I don't think this one is exactly the same as the one I took off. Will it matter which one it is if I am going to use the points and not convert or am I stuck with either repolarizing and converting, or getting a different armature. The engine did run pretty well after I put the new armature in last year but then after being parked for a while there was no spark.
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Bob, I believe that is correct; a non-Magnetron flywheel magnet polarity is "South" and thus the compass will point North. Check/search the archives for "Magnetron" and you should see the various topics & threads which discuss this. I think some folks have recently sent their flywheels back to Briggs for re-polarization (so the service should still be available). Tom(PK)
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I am pretty sure all of the more modern cast iron Briggs that originally had points will need the flywheel repolarized for use with Magnetron. Briggs will do it, and some good antique tractor magneto repair shops can do it. You would want to leave the original points push rod and points in the engine - otherwise you wil have an open hole and oil will leak out. Or, come up with a plug. With as much as points and condensor cost anymore, doing the Magnetron conversion on an engine that needs point now is well worth it. Less long term expense, and less maintenance. The only potential problem is an engine with a weak starter or starter/generator. Magnetron requires about 350rpm of cranking speed to create spark. Tim
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Actually the more "modern" B&S cast iron singles did not have points (units built after 8/1/1981). The blocks were also not machined for the points setup (plunger hole bored, screw holes tapped, etc). I also tried to get a reputable old-school magneto guy to repolarize my flywheel but his machine could not do it. Seems like the Alinco type of magnets require a lot more power to switch the polarity. As far as removing the points plunger bronze guide, I used a 3/8" cup type welch plug to seal the block. Tom (PK)
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Mine is a 1964 so I am pretty sure it will need to be repolarized. I have another engine which runs well so this may be the time to see if I can get this flywheel done.\ and use the pther engine until I am finished this one. Is there Briggs place in Canada that can do this or do I have to sned it to the U.S.? I guess shipping might cost a bit due to weight.
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By modern, most people recognize the engines with the 6 number model - like a 326437 or 170702 etc.. as being modern. The old lettered or letter/number engines are definetely not modern. Take a points type 16hp cast iron engine and a later factory Magnetron one, and the differences are really only in the ignition - granted they lost the provisions for points. Tim
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