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INSTALLATION INSTRUCTIONS FOR THE SINGLE MAG HOUSING



1. When using 8 dowel crankshafts, the flywheel end piece should be machined for the additional dowel pins.

2. Install end piece to crankshaft, torque bolt to 100 ft. lbs. and measure end play.

3. With case halves together, lay mag housing against case with the four #21 holes in line with the "X" web on the back of the case.

4. Using a #21 drill, drill and tap 4 holes one at a time into the engine case. The tap is for an 10/32 screw.

5. With flywheel end piece installed and housing bolted on, bring the right front cylinder up to 28 degrees BTDC (Before Top Dead Center) on the power stroke. Time magneto and reference the mag drive orientation. Install mag drive to flywheel end piece using 3 screws provided. They should be installed with locktite.

6. Install mag drive puck and mag. NOTE: because of slight differences in cases, you may have to machine off the surface of the mag housing to let the mag engage the puck and drive more, or you may have to add a small aluminum spacer to set the mag back slightly from the housings surface or sand the micarta mag drive puck.


NOTE: The mag drive hubs tangs should be in the 1:00 and 7:00 position when engine is at 28 BTDC (before top dead center).



Mag drive hub tangs




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