I have a relatively new (under a gallon through it) ST 75. It has a 12/6 APC prop. It was running hot on the fuel I used. Turns out the fuel had 10% oil. I have since added Klotz oil to bring it up to 18%. I reset the high & low speed needle valves. The engine now runs cooler, idles for minutes and transitions to high speed well. My question: If I add 2 ounces of Castor oil to protect against a lean run, would this change the high or low speed needle settings? (more oil per cycle)
Thanks in advance. Tony.