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Tiring to get my RV6A off the ground but have some problems to solve. I have an 0-320 H2AD freshly overhauled in the aircraft. The first time I ran it it seemed fine but I did not do a mag check or run it over 1600 rpm. Cht,s where all in the mid 300,s and I had one cylinder with a higher EGT (#3) than the others, since then I have be told this is normal.
I borrowed a timing box and thought I would check the timing, what I found was the left mag was about 1 Deg ahead of the other. (H2AD has 2 mag,s in one) A local A&P told me it might not make much difference so try it as set, and see how much mag drop you get. So I timed to 25 deg advice and ran the engine up. It seemed ok but when I ran it up to 1800 I would a 25 rpm drop on one and a 200 rpm drop on the other I also got much higher CHT,s , The cowling was on this time which would account for some temp rise but when I did a high speed taxi (55-60 mph) the temps climbed to 450 (Lycoming says 500 deg is max but I think that?s too high) so I backed off put the plane away and when home.
The following weekend I removed the cowl and rechecked the timing which seemed ok. I replaced a suspect plug and ran it up again, same thing 25 ? 50 rpm drop on left mag 200 rpm drop on right, CHT,s were back to 350 ( No cowl) but when I tried to go above 1800 rpm the engine began missing. I now have the mag on my work bench, I made adjustments to the internal timing so that both contacts open within ? deg of each other at the 8 deg ?E? gap position. There are two windows where you can view the gear teeth, both left and right. When I line up the mag to the ?E? gap mark one red tooth is dead center of the window and the other is off by ? tooth.
Questions:
? Any Idea why my CHT,s would be getting so high with the cowling on
? What would cause the missing above 1800 rpm,s
? Why dont both red teeth line up in the center of there respective windows.
I was hoping to get my first flight in in the next few days but it does not look good, so any help would be more than appreciated.
Thanks