Jump to content

Unofficial Home of Old Simplicity & Allis-Chalmers Garden Tractors

Sign in to follow this  
patrician12

points magneto vs.points coil

Recommended Posts

patrician12
I saw the post about remagnetizing the Briggs flywheel.Did anybody ever try to use the magneto points with a condenser to fire a standard coil like a Kohler set up???

Share this post


Link to post
Share on other sites
Brent_Baumer
Yes. It has been discussed on here many times. There are even instructions on how to wire it on the Do-It-Yourself section on SimpletrACtors. Works well and is easy to do. Brent

Share this post


Link to post
Share on other sites
stumpy
Only way to go...spark is hot regardless of weather conditions too. Any 12 volt coil will work, as long as it is the INTERNAL-BALLAST TYPE, like the ones from Kohler. If you use a non-ballasted coil you will have problems, perhaps not immediately, but sooner or later. I usually end up mounting the condensor on the coil when I re-do things...one less item to clutter-up the tight spot under the points cover...seems to work just fine.

Share this post


Link to post
Share on other sites
HubbardRA
I have a 10 Hp B/S that has had a points-condenser-coil ignition for over 15 years. I started out with a motorcycle coil, which ran great till the coil died 10 years later. I now use a Kohler coil. If you use an automotive type coil, you will need to add an external ballast resistor like was used on the older Chrysler vehicles. Without the ballast, points will not last long.

Share this post


Link to post
Share on other sites
thedaddycat
The blown engine from the 3416 has that kind of coil, "Use External Resistor" printed right on it. The wiring was also rigged to work, coil power was "crimp" tapped into the ignition switch for power, lights and lift wired off another power tap. I have not found the resistor yet....

Share this post


Link to post
Share on other sites
HubbardRA
Kirk, Many times people will use a non-ballasted coil because they don't know the difference. This will work, but it will burn the points much quicker because they draw more current across the points. On an car, the non-ballasted coils were used with external resistors, or resistance wires, so that the resistance could be bypassed during starting for more ignition energy, but returned to ballasted operation when the ignition key was released to the run position. You can install a ballast resistor and install a solenoid from a 60s-early 70s Ford which had an extra terminal to hook to the bypass wire when the starter is engaged. This way you can have un-ballasted starting, with ballasted running. If it starts good you don't need the bypass feature.

Share this post


Link to post
Share on other sites
Agricola
Doesn't there have to be a change in ignition switches also? Does anyone know the resistance and wattage of the external resistor used in the non-internal resistor type coils? I have a bunch of old wire wound resistors and would gladly give them up if they would work.

Share this post


Link to post
Share on other sites
HubbardRA
John, The resistor is used to drop the voltage from 12V to approximately 6V. You would need to measure the resistance of the coil to figure it out. If I have one of the resistors at home I'll measure it.

Share this post


Link to post
Share on other sites
Agricola
Thanks Rodney, If they work, I'll put them up in the classifieds for shipping cost only. John

Share this post


Link to post
Share on other sites
HubbardRA
I also have a box of large wire-wounds that was given to me at a yard sale. Hadn't thought of using them as ballast resistors. Hope I have the one at home that I can check to determine the value.

Share this post


Link to post
Share on other sites
HubbardRA
John, The value of the Chrysler ballast resistor is 1.0 ohm.

Share this post


Link to post
Share on other sites
Spencyg
I did this when I rebuilt my 16hp CI briggs on my 7016H this spring. I can only say that it has made the starting and running of my tractor very very nice. It starts as easily as my car now instead of having to crank over and over to get the magneto firing. I ended up using a coil from a ford truck. It has an external ballast resistor, and works great. I did have to modify the key start wiring because when you turn to "start", it will cut power temporarily to the coil. I ended up installing an ignition switch to power the coil, and the start/run function is used to run the starter and 12V accessories. Good luck...you will love it. Spence

Share this post


Link to post
Share on other sites
Agricola
Spencyg, If it was losing power to the coil when you went to start, you might have had the coil wire running the accessory position. That terminal is dead when you are in the start position. I remember my folks turning off all the accessories when they started the car. I finally clued them in on the "modern" technology of the day.

Share this post


Link to post
Share on other sites
Guest
This topic is now closed to further replies.
Sign in to follow this  

×