Install wico

Hi, I need help to install a wico C mag into the gear on a 39 model "L" I have it on TDC but now I"m stuck.. Need help. Thank you Edd

I dont know much about that L but do know a lil something about that MAG. It fires on BOTH TDC's the Compression plus Exhaust so if its installed 180 out (it fits in either way) a simple top n bottom plug wire reversal would make it still run. Original is top cap tower to left cylinder bottom to right...(if its not that way you can remove mag n rotate its drive OR flywheel 180 n reinstall) The mag has to first fit into the open female slot (turn mag or flywheel so it gets in) and then once its in the way to check the start/impulse timing is to hear if it SNAPS (impulse spring winds then releases snaps) right when the left piston passes over TDC which, (on a tractor) is when a Left hand Impulse (LHI) mark on the flywheel is lined up with a flat mark at the 3 o clock position i.e. left piston is at TDC THATS WHEN SHE NEEDS TO TRIP/SNAP/FIRE. If you loosen the mag in the flange and rotate it that changes when she snaps/impulses and that also affects the run time advance position, but she still needs to be adjusted (rear lag angle or mag rotation or both as required) so she snaps/impulses right at TDC for best starting........ To change that (when she snaps), loosen n rotate the mag in the flange and/or adjust the rear lag angle (see below) by loosening the 4 rear screws and rotating
the stop plate, each lil index mark = 5 degrees and top center is 12 1/2 so 2 1/2 marks off top center would be 12 1/2 + 12 1/2 = 25 lag angle, while 4 1/2 index marks off top is 35 lag angle


I FIRST adjust the rear lag angle to match whichever drive cup I have i.e. if its a 25 degree advance drive cup I set the lag angle to 25 but if its say a 35 degreee advance drive cup I set it to 35 THAT (rear lag angle adjustment) AFFECTS START/IMPULSE TIMING ONLY it dont affect the run time advance.

It takes a timing light to see where the run time advance is but you need to set the rear lag angle to match whatever drive cup you have then fine tune adjust the start/impulse timing EITHER by mag rotation and/or the rear lag angle so she starts at TDC (so impulse snaps when left piston is at TDC and flywheels LHI is at 3 o clock)

I spend like 30 minutes on this when I give my Wico Seminars at John Deere shows but I cant cover it well or explin it here in a couple paragraphs, sorry. Hopefully this will give you the basics.

John T

John
Thank you, I"ll try it today and let you know. Edd