March 2013, 675 hours, Low compression, blow by @ rings & two leaking intake valves.  Major issue is with baked carbine on pistons, stuck rings and oil starvation @ top of heads.  New pistons and new hallow rod & valve system assem.  Need control of mixture so we are going with Rotec TBI, dropping Bing.  Will report.

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Comment by Randy Jensen on April 8, 2013 at 4:54pm

there is an article in kit plane mag , with in past 6 months . to do with cowling pressure . there should be 8 inches difference in pressure between intake and exit . they diagrammed the test method using clear plastic tube led from cavities to cockpit -2 separate tubes , in the cockpit make a vertical U in each tube . tape them to a ruler and pour water in each till levels are equal . go flying and adjust inlet and outlet untill you get 8" . it will probably get you think ing about in flight adjustable openings

Comment by Randy Jensen on April 8, 2013 at 2:18pm

l sure appreciate engine reports and pictures . hope the new system gives you the mixture control you are hoping for

Comment by Mark Maltais on April 7, 2013 at 8:58am

WOW, that's a lot of issues at 675 hours. Any thoughts on a main cause?

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