magnito hit miss

[Kevin]

i have a 49 cub with 6 volt negative ground with a magnito.
the problem is it won't start not sure what to check I cleaned all connections and points and coil in the side of magnito. It seems to get a very slight spark and then it has none. I wanted to know is there a way to check the output of the magnito. any ideas to check or change something.
thanks for any suggestions

[Donny M]

Kevin,

The first place I'd start is to remove the kill wire on the mag. This is on a stud on the lower outside of the magneto. Once you remove the kill wire check to see if you have good spark. If not re-check the points (.013" gap) making sure they are closing. Also make sure none of the internal wires are touching ground (side of mag). If all these things are good then you may have a coil going bad but check the simple things first.

Good luck, let us know

[Rudi]

Kevin:

First, let me say welcome to the Greatest Forum on the Net and to the Cub Family

Second, might I suggest that you read New Members and Visitors, Please READ. The Cub FAQ's are filled with a lot of really good general knowledge and the Cub Info has some good trouble shooting tips. The Best of H.L. Chauvin puts a humourous yet very helpful tone to fixing your Cub. The Won't Start articles will be really helpful. Also, the Cub Manual Server has lots of info to assist you as well.

As for beginning to look for the problem, you need to have three things in order for your Cub to start. Fire, Air and Fuel. If any one of those three is missing - No Start. Check your plugs to make sure each one fires. Then check your air - either too much or not enough. Then check your carb.

Again, Welcome to the Cub Family

[Kevin]

Is there a way to check the coil . also the previous owner said it would start to sputter for a few minutes.then next time sputter more then finally it wouldn't start anymore.does that still sound like the coil. I can't see any wires touching where they aren't suppose to .
thanks for the help
hope this doen't seem like a dumb question but this is all new to me

[Bigdog]

Kevin, if your points are set correctly you should get a bright blue spark about 3/8 to 3/4" in length from the mag coil secondary post. If you do not - the most likely culprit is the coil. You could have weak magnets in the mag but the description from the previous owner sounds very much like a failed mag coil. But I would re-check the points and condensor and make sure they are OK before I dug into the coil.

[John *.?-!.* cub owner]

Kevin, if you're jsut trying to get it going rather tan a restoral, it is easy to convert it to a battery ignition coil, and much cheaper.

[Kevin]

what do i do to convert it to a battery ignition coil? should it be 12 volts or 6 volts?how do i hook up the external coil?

[Bigdog]

First of all, you mentioned that your system was 6 volt negative ground. The 6 volt systems were originally positive ground. That will affect how you connect the external coil for the conversion so you need to decide if you are going to leave it negative ground or change it to positive ground.

To convert - first remove the internal mag coil to prevent back-feeding. You will need to change your on-off switch from a kill type switch to a standard two terminal normally open switch. Run a wire from the battery hot terminal to one side of the switch, then from the other side of the switch, run a wire to where you are going to mount the external coil. Mount the coil making sure you have a good ground. Now, connect the wire from the switch to the coil primary terminal that is the same polarity as the battery hot post. Remove the kill wire from the distributor side post and connect a wire from there to the other coil primary terminal.
Use a 6 volt coil since you have a 6 volt system.

[John *.?-!.* cub owner]

I would suggest also installing a fuse between the battery lead and the switch.

[Kevin]

first I would like to say thanks to everyone who replied
I changed the internal coil in the mag and it fired right up in about
2 seconds of turning over. I next question is it seems to be 12 volt.the
tractor came with out a battery and previous owner new very little about
the tractor.I had it running and checked the battery cables with a voltmeter and it was reading between 12.8 and 13.8 volts.Will this effect
the mag at all or doesn't it matter.Also the headlight bulbs are all changed
is there anything I should do?
thanks again everyone
this really seems to be the greatest forum

[Donny M]

Kevin,

The magneto doesn't care about the battery voltage. If you measured around 13 volts put a 12 volt battery in it (I assume negative ground) but since you have a volt meter you will know for sure.