WICO MODEL X SPEC XHD 265 Farmall A

Thanks for the help so far...Exploded diagram of a Wico X shows a rotor with what appears to be gear teeth on the outside (Rotor was missin'when I got into this Mag.) Lookin'at the magneto seems to be a gear drivein' the rotor, rotor spins on a shaft on a bar that runs across the magneto body...Bear in mind I've been timein'engines since the first Model A Ford I bought in the mid 50s, I don't claim to be a mechanic, I know to get # 1 cly TDC compression stroke, timein' marks lined up and start from there. Question is, since this rotor doesen't have a flat spot to match up with a flat on the shaft, (I haven't got a look at a rotor yet, may have ask too soon) what clue do You have as to how to get the rotor in the right place the first time, seems like it would be easy to be off several gear teeth.....The mag has what the book calls a window altho I can't see thru it....might need cleanin...Thanks for the help

Wild Bill

Wild Bill, Im not sure what exact Mag youre dealing with, but on many mags where the rotor tip is just prior to when the impulse spring winds up n then trips IS NOT DEAD LINED UP WITH THE TERMINAL TO WHICH ITS GOING TO DELIVER A SPARK JUST SHORTLY AFTERWARDS (its physically located JUST BEFORE the place where it will be after/when the spring trips) ...... Theres no spark until the impulse trips, and when it does the rotor tip ONLY THEN passes by that correct terminal so the saprk jumps from the rotor tip to the caps terminal. I AM FAMILAIR with the Wico C and X (NOT XHD) Mags used on Two Cylinder Deeres and to time them as I say the rotor tip IS NOT where its going to be AFTER the spring has wound up n then tripped.

I time them (Wico C and X used on Deeres) to the point the mag trips/impulses/snaps right as the No 1 piston is at TDC and prior to snapping/tripping the rotor tip is JUST BEFORE the upcoming No 1 cyliners inner cap terminal. One can first RETARD THE TIMING, then get the piston to TDC, then slowlyyyyyyyyyy advance the timing just to where she snaps/trips

Hope this helps even though Im not familiar with your particular mag, let us know

John T

If you turn it backwards and watch when the points are just closing, that is the point of firing. Put the rotor gear on to line up with a terminal in the cap and it should be right.

The instructions don't cover that, eh?

There may be timing marks on the rotor and on the drive gear.

Otherwise, turn the mag 'til the impulse snaps, then closely watching the points, turn it BACKWARDS 'til the points are just at the open/close point. The rotor must point EXACTLY to one of the terminals in the cap.