RE: 4 Star 60 Pushrod Conversion...
OK with the new hole in my fire wall I was ready to install a new pushrod.
To my dismay I had to rob one of the nice pushrods from my RV-4… Not pleased but as I mentioned I want this Airplane finished.
A few bends need to be made in the push rod between it exiting the firewall and connecting to the carb. I can’t really explain exactly how to do this but it requires a bit of trial and error.
I used a piece of paper and pen first to measure the fundamental bends and then used a scrap piece of pushrod to practice on and ensure my bends and calculations worked.
I then worked out how long the push rod needed to be taking into account the bends and distance to the servo. Then I cut the pushrod. The length only had to be exact to the nearest inch because the servo end is threaded and so I have some adjustment in the clevis. I got it pretty much right though.
I tested everything and it all worked out. You may find you have to make very minor bends in the pushrod here and there to stop it binding but it is a pretty straight run to the servo after the difficult bends up to the card.
I also soldered a cross member where the major 90 degree bend is to stop any flex.
See pictures…