The original engine installalation for the RF3/4 had a decompressor which when pulled, cracked the exhaust valves on the right bank and broke the pneumatic lock allowing the engine to turn. I owned a RF4 which had lost this function after an engine replacement and no amount of diving/yawing would turn the engine.
I used to turn the engine off in good soaring conditions - but you had to have fairly large gonads or very good soaring conditions to do this. I got caught out once - landed in a large field, hand swung the engine and took off again!
Great days!
