Subject: Front hub drama
From: ACRE
Date: 5/24/2003, 8:33 AM


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.<<<<
Paul Lamar


Al Gietzen wrote:

How about this approach.  Center apex seal in trailing plug hole, temp
mark on pulley, same for apex seal in leading plug hole.  Apex seal is
then at TDC point midway between the two marks.  Measure with either
protractor or distance along the circumference.  180 degree rotation on
the e-shaft (60 degrees on rotor) should then take you to TDC. Make a
mark at the pointer and go from there. Unless it's not valid for some
reason, you may find it a bit easier especially once your engine is
mounted up-right.  It assumes, of course, that the leading and trailing
plug holes are equi-distant from the TDC point.

That's what we did to resolve the mismatch of pointer and timing marks
on my engine when doing the dyno runs.  Based on pressure transducer
traces it seemed good.

Al

The plugs are not equal distances from TDC Al. Your timing is off a bit.
I think the leading plug (lower plug) is 23 mm and the trailing plug (upper
plug) is 30 mm from the axis. I am not sure about the exact numbers
as these are from the 1981 book Rotary Engine by Kenichi Yamamoto. 
However, a quick glance at the inside of a rotor housing will verify 
that the distances are unequal. 

Paul Lamar
 
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