Rotorway Forums

Several years ago Joe Huff asked me if I would be a flight tester for the 172 engine that he was developing. I agreed knowing that this was going to require at least a couple of engine removals and installations. Joe shipped his first version to me for installation in my own 162f. If you have done an engine swap you know that it takes some considerable time and effort to accomplish. I flew that first engine for about 25 hours then hauled my helicopter down to Texas to remove and disassemble the engine to check all of the internal components.

Joe took it apart, made some modifications, put it back together, ran it on the dyno and then we installed it into my 162f for flight testing. We repeated this process several times until Joe was satisfied that the engine design was ready for the Rotorway community. Following are photos of Joe in his immaculate workshop assembling the final version of my 172 engine and installing it into my Rotorway.

When was the final version installed and how is it doing?

(07-09-2026, 12:31 PM)Sam Oliver Wrote: [ -> ]When was the final version installed and how is it doing?

The final version was installed about 3 years ago and is doing great. I change the oil every 25 hours and check the valve lash adjustment. It just purrs.

what are the aluminum elbow fittings at the top of each cylinder head for? oil lubrication or for case ventilation?

Those are crankcase breathers that vent into the top of the oil tank. The tank comes stock with two vent inputs at the top front passenger side. Those two vent inlets are capped/plugged by the factory and not used in the factory configuration. The stock engine vents into the oil tank through the bottom of the head along with the oil from the rockers. The factory epoxies a plug into the top of each head where Joe installs the breather fittings. Joe likes his engines to breath unrestricted and by venting at the top of the head only oil mist and crankcase gasses vent out the top then the oil tank recovers any oil before the gasses exit through the oil filler vent tube which takes the vapors overboard.