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I reported my first problem in the last post.  I had cut the push rods just a little too long.  I double checked my push rod measuring tool and found it to be at the limit of travel down.  I modified it and measured again and came up with a length just slightly shorter than what I had, which seems right.

I tried getting the ends I put on off with no success.  I ordered four more just in case and decided to move on with the other head.  With luck maybe they would fit!

The first picture is of the mineral spirit bath of the rocker assembly parts for the second head.  I put these all back together and the already cut push rods fit.  I cut new ones for the other side and installed them.

The second picture is supposed to be the next ‘Ta Da’ moment with all the push rods in place, the rockers arms all adjusted and the head covers on.  It is but there is a big problem.

I ruined the second head.

      I had both heads on and torqued down before I put the rocker arms on. That is when I did the cutting of the studs I talked about in the last post.  When I went to put the rocker arms on the second head I noticed I had – nicked is not nearly a strong enough word – sliced about a third of the way through a stud that holds the rocker arm assembly in place.  I had also nicked a spring for good measure.  Both of the pictures below show the affected parts.

      The spring could be replaced and Sonex sells them.  The stud could theoretically be replaced also, but I’d have to find a stud and probably get a machine shop to take this one out and put the new one in.  I may do both in the future, but for now I ordered a new head.

      One of the selling points of the Aerovee engine is it is a lot cheaper to rebuild than an airplane engine. $280 for a new head is very cheap for airplanes. Especially because this is a part that Sonex has to do some special machining to convert it to airplane use – they add two additional spark plugs holes.

      In a year of building, this is my first mistake that I had to fix by buying more stuff. (I think).  I have messed up plenty of pieces but have always had enough scrap on hand to make a new one.