"Brian D. Cain" wrote:

Hey folks, I've been dealing with an issue regarding the Atkins Rotary
ribbed-belt
pulley kit for quite some time.  The problem I'm facing has to do with a
lack of timing
markers on the crank pulley.  I believe I posted on this before several
weeks ago, but
I'm still fighting this issue.  I thought I had it nailed, but I'm not so
sure anymore.  The
thing I've run into deals with apparently two different style Mazda front
hubs:  On their
respective backsides, there's a marked indentation that seems to indicate a
certain
bolt-pattern offset (as we know, the crank pulley's bolt pattern is
assymetric and can
only be bolted on one way), and I've got one front hub that has two of these
indentations
and two other front hubs that have only one!  When I compare the two
different hubs,
the bolt pattern for the crank pulley is offset by atleast 15 degrees.  This
makes trying
to get accurate timing marks on this aircraft pulley set a real confusing
pain in the
rear-end.  While I'm impressed with this pulley set, I can't seem to get
this thing timed
right.  The "ear" tuner instrument is telling me it's still off although the
engine isn't showing
any signs of advanced timing pre-ignition or retarded timing sluggishness
and low throttle
response.  Anybody else using these pulleys and/or familiar with this drama?

Thanks,

B

I would go back to basics Brian and check for top dead center.
I think the best way to do that is start with a junk spark plug
and hollow it out. Attach a clear plastic hose about 12 inches
long. Screw it into the lower spark plug  hole in the front rotor housing
Screw another plug into the top hole to seal it.

Get the rotor near top dead center and fill the chamber with
motor oil. Rock the e-shaft back and fourth and watch the column
of oil in the tube. When the oil is at the peak... mark the pulley
adjacent to the pointer on the front cover with a bit of white
paint. That is top dead center. Remove the pulley and use a protractor 
to layout any timing marks you need such as 22 degrees BTDC.

This works no matter what screw ups were made when the pulley
was machined.

Paul Lamar
 
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