Magneto rotor position

[edwinbarnes]

I was unaware that the rotor was geared prior to removal (1947 Cub ). I didn't notice the position prior to removal. Where does it need to be positioned when #1 Is at TDC?

[staninlowerAL]

Welcome to the forum. One more post and you can access the pdf manuals at the Quick links tab, top left corner of this page. Look for GSS 1012 Electrical Equipment for detailed info on the J4 magneto maintenance, repair, timing, installation. The rotor and pinion gear assembly have timing marks that must match for it to be in time and the rotor must point to #1 plug wire TDC on compression stroke. It's all in the manual. Good Luck and keep posting.

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

It is also in the How to section.
viewtopic.php?f=140&t=83108

[Glen]

Hi,
The rotor points straight up, for number 1 cylinder. Number 1 spark plug wire connects to the top post on the distributor cap.
Also, the Cub owner's manual says clean the area around the gears, and apply new grease to the gears.

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

Glen, are you making fun of my dirty grease looking rotor? That one had been cleaned and new grease a few months before, and I just pulled the cover off and marked the indicator line on the rotor for the How To posting.

[Glen]

Hi John,

Sorry if you misunderstood, no not making fun of it. That is how they look after using with new grease in the gears.
I put the pic there so edwinbarnes, or others, could see the gears are supposed to be greased. The cleaning meant the old, hard grease cleaned out before putting new grease in.

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

I was just making a joke Glen, I understood the reasoning for the statement, it is one I should have posted with my earlier link to the How To. That is why I put the laughing face in it. Thinking it over, I am not sure if that is one I greased a few months before, or if it is just one I had laying on the shelf. Those 2 pictures were taken in March of 2014, I am lucky to remember what I did yesterday, much less 4 1/2 years ago.

[Heatwrench]

I realize this is an old post, but thank you Glen for posting it. I was beating my head against a wall tryin to figure out HOW to time this thing. I’ve got three cubs and only ONE with a j4. Pulled it apart the other day because tractor just didn’t want to start. Before that, it would only start when it WANTED to. Found a LOT of CLEAN oil in the points compartment which, leads me to believe the previous owner OVER oiled the bearing assembly?? Anyway, I’m cleaning the entire thing and re assembling it today. So your post and pic is VERY helpful. Thanks. Next, to get a service manual on the mag.

[Don McCombs]

Once you have made two posts, the Cub electrical service manual is available by clicking on Quick Links in the upper left corner of this page, then PDF Manuals.