OceanSailer, that's the first I've ever heard of that. The loads are different, because the mounts have to absorb torque as well as thrust, but every engine mount I've seen will do both push and pull. Are they getting squishy? Engine shifting with load on the prop?
, I'm concerned that there may be a major inbalance in your system. If the mounts are worn out, I'd expect a big clunk when load goes on the propeller
and another clunk when the propeller
loads the engine, but between those two events
the engine should be leaning on one side and pulling on the other.
OK. Two metal parts
, one the mount to the frame and the other the bolt to the engine. Contained in a rubber molding capable of keeping everything in place while absorbing torque in both directions and vibrations. Your alignment does not go to hell just because you added RPMs. Your engine does not shift noticeably or go clunk because you went from forward to reverse. No run-out in the prop shaft.