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Best to use a degree wheel to set timing....spoke in hole is too crude. There is a degree wheel that can be downloaded on this forum. Wedge a piece of wood or rubber tubing into the AAU to fully advance the unit. AAU springs should be new or known to be of proper tension. AAU should return to retard position without any sticking or hesitation before wedging.

Remove both plugs.. Look in left cylinder plug hole as you rotate engine in a forward direction with a wrench on the cam sprocket nut. When the left cyl intake valve comes into view, then disappears, the left cyl is coming up on compression stroke. Now use a spoke in left cyl and rock engine to sense when left cyl is at TDC. Now align degree wheel at zero with a pointer fabricated from stiff wire and attached to one of the stator mount studs.

Now remove magneto contact breaker center screw. Attach one lead of a volt-ohm-meter to the lug that secures the contact breaker spring. Find another point on the contact breaker that registers continuity when the points are closed, and open circuit when the points break, and attach the other VOM lead to this point.

Now rotate the engine backwards about 50 degrees, then slowly forward until the VOM registers point opening. Repeat several times to get an average reading.

Now rotate engine forwards 360 degrees and repeat the above procedure to get a reading when the right cyl registers point opening. The readings on both cylinders should be within 2 degrees....if not the cam ring will need centering..

Assuming both cylinders are registering points opening within 2 degrees, now re-set the AAU on the magneto shaft so the points open at 32 degree BTDC (factory spec for Atlas advance...you may want to set this to 30 degree or even 28 if you have high compression pistons), Check both cylinders to ensure both cyls fire within 2 degree of each other.

Replace center screw on contact block, remove wedge on AAU. Timing should now be proper and engine should fire up.

If cam ring is off center, reply for procedure to bring cam ring into center.

Slick

<blockquote data-quote="texasSlick" data-source="post: 241398" data-attributes="member: 4732">Best to use a degree wheel to set timing....spoke in hole is too crude. There is a degree wheel that can be downloaded on this forum. Wedge a piece of wood or rubber tubing into the AAU to fully advance the unit. AAU springs should be new or known to be of proper tension. AAU should return to retard position without any sticking or hesitation before wedging.Remove both plugs.. Look in left cylinder plug hole as you rotate engine in a forward direction with a wrench on the cam sprocket nut. When the left cyl intake valve comes into view, then disappears, the left cyl is coming up on compression stroke. Now use a spoke in left cyl and rock engine to sense when left cyl is at TDC. Now align degree wheel at zero with a pointer fabricated from stiff wire and attached&nbsp; to one of the stator mount studs.Now remove magneto contact breaker center screw. Attach one lead of a volt-ohm-meter to the lug that secures the contact breaker spring. Find another point on the contact breaker that registers continuity when the points are closed, and open circuit when the points break, and attach the other VOM lead to this point.Now rotate the engine backwards about 50 degrees, then slowly forward until the VOM registers point opening. Repeat several times to get an average reading.Now rotate engine forwards 360 degrees and repeat the above procedure to get a reading when the right cyl registers point opening. The readings on both cylinders should be within 2 degrees....if not the cam ring will need centering..&nbsp;Assuming both cylinders are registering points opening within 2 degrees, now re-set the AAU on the magneto shaft so the points open at 32 degree BTDC (factory spec for Atlas advance...you may want to set this to 30 degree&nbsp; or even 28 if you have high compression pistons),&nbsp; Check both cylinders to ensure both cyls fire within 2 degree of each other.Replace center screw on contact block, remove wedge on AAU. Timing should now be proper and engine should fire up.If cam ring is off center, reply for procedure to bring cam ring into center.Slick</blockquote>

[QUOTE="texasSlick, post: 241398, member: 4732"] Best to use a degree wheel to set timing....spoke in hole is too crude. There is a degree wheel that can be downloaded on this forum. Wedge a piece of wood or rubber tubing into the AAU to fully advance the unit. AAU springs should be new or known to be of proper tension. AAU should return to retard position without any sticking or hesitation before wedging. Remove both plugs.. Look in left cylinder plug hole as you rotate engine in a forward direction with a wrench on the cam sprocket nut. When the left cyl intake valve comes into view, then disappears, the left cyl is coming up on compression stroke. Now use a spoke in left cyl and rock engine to sense when left cyl is at TDC. Now align degree wheel at zero with a pointer fabricated from stiff wire and attached to one of the stator mount studs. Now remove magneto contact breaker center screw. Attach one lead of a volt-ohm-meter to the lug that secures the contact breaker spring. Find another point on the contact breaker that registers continuity when the points are closed, and open circuit when the points break, and attach the other VOM lead to this point. Now rotate the engine backwards about 50 degrees, then slowly forward until the VOM registers point opening. Repeat several times to get an average reading. Now rotate engine forwards 360 degrees and repeat the above procedure to get a reading when the right cyl registers point opening. The readings on both cylinders should be within 2 degrees....if not the cam ring will need centering.. Assuming both cylinders are registering points opening within 2 degrees, now re-set the AAU on the magneto shaft so the points open at 32 degree BTDC (factory spec for Atlas advance...you may want to set this to 30 degree or even 28 if you have high compression pistons), Check both cylinders to ensure both cyls fire within 2 degree of each other. Replace center screw on contact block, remove wedge on AAU. Timing should now be proper and engine should fire up. If cam ring is off center, reply for procedure to bring cam ring into center. Slick [/QUOTE]

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