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Alright Mooney group bear with me, this may get a little long winded. New Pilot and even Newer Mooney pilot. So, i just finished my 15 hours to be checked off by insurance. I now have about 20 hours in my new (to us) 1967 F model. We bought it with about 25 hours on a new engine, and just completed our first oil change as well. Lots of firsts going on here. So, I am new to complex aircraft as well. When performing our run up we normally lean the mixture to best power similar to what we did in the 172. Run up to 1800 rpm, full forward on the prop, and slowly lean until power loss catch it and give a few extra turns once the power is back. Then we pretty much haven't touched the mixture on any flight. I played with it a little the other day in cruise, lowering it until it got rough and then adding it back in until it was smooth. Our checkmate checklist says cruise around 2600 rpm on the prop, but once setting the prop you cannot use RPM as a good lean indicator correct? Plus to add to complication our fuel pressure gauge is out (so I cant just put it at the bottom of the green) which would be running it efficiently correct? (Also new avionics coming in a couple months) So the only time I have tried to lean it in flight was in a cruise the other day I leaned it until it ran rough, then twisted it back in to run smoothly. Which the POH says don't lean the power above 75% power... but at full throttle I am sure I am above that. Did I hurt the motor? How on earth do you calculate percentage of power? Then there is the throttle. I figured on a brand new engine you wouldn't want to run it at WOT all the time due to wear on a new engine. But my CFI said run it full and manage RPM and Fuel flow with the mixture and prop, but my Dad (Airforce Pilot/commercial pilot of 30 years) said he would also be worried about wear on the engine, but thoroughly admitted I probably have more experience in a civilian airplane than him at this point. Ours is also turbo normalized as well, and all I have been told about it is to keep it below 28 MP. All of this has added a ton of confusion in my mind, so I went to the internet. Specifically another post on here: Which added even more confusion. I also realize I probably sound like an idiot, but I am okay with that if it helps me figure all this out by asking the experts. So to summarize my questions: 1) Is our best mixture practice during run up correct? 2) When leaning for efficiency, can you use RPM drop with a constant speed prop, fuel pressure indication, or leaning it until its rough then adding it back in? Which is correct or are all correct and some are just better than the other. 3) Is WOT the correct way to fly? Is the POH out of date as stated in the message board above. 4) Is 2600 RPM that the checkmate suggests the best cruise setting on prop? 5) Have I hurt the engine buy leaning with full throttle in and potentially getting over 75% power setting? 6) How on earth do you correctly measure % of power? (This one is probably easy but I am missing it) 7) Does any of this change when adding in the turbo? Thanks everyone!!! I know that is a lot to follow but any response, guidance, or videos would be much appreciated. Fly safe, The FNG

228AL_checklist.xls View File Requested post of my LOP file for 200hp Lyc IO-360. Submitter Gry101 Submitted 05/09/2020 Category Performance Data

Just had two epiphanies about power settings for LOP. Haven't tried either yet but I will on my next flight. #1 1. Power output is determined by fuel flow when LOP. 2. Approximate fuel flows for a 200 HP engine are: 10 GPH = 75% 9.3 GPH = 70% 8.7 GPH = 65% 8.1 GPH = 60% 3. To set my desired power setting I can level at cruise altitude (I'm assuming something reasonable like 6000+) I can set an initial RPM with WOT then lean to LOP. I personally like all cylinders to be in the 10 to 30 LOP range. I can then check the fuel flow. If it is higher or lower than my desired power fuel flow, I can adjust the RPM to get what I want, then fiddle with the mixture to ensure I'm still LOP. Adjusting RPM should have minimal impact on mixture. For example, let's say I want 65% power or about 8.7 GPH. I level off, leave the throttle wide open, set 2400 RPM, and lean to LOP. I then note that my fuel flow is only 8.3 GPH. I could increase my RPM to about 2500 and I should see the desired 8.7 GPH. I would then fiddle with the mixture to see if all the EGT's increase if I richen or decrease if I lean. If they do, I'm still LOP and all set for 65% power. Using the Normalize EGT mode on a JPI should make it easier to check. #2 If I have my power set to the desired level but my CHT's are a bit higher than I like; further leaning with an increased RPM that results in the same fuel flow should give me the same power output (but I'll lose a little to friction) but with lower CHT's. That's because higher RPM puts the peak pressure further past TDC. Further leaning has the same affect. Therefore I'm doing two things that put my peak pressure further after TDC. That should decrease peak pressure and lower my CHT's. That is, if 20 LOP and 2400 RPM is too warm, I might be able to get the same fuel flow and lower CHT's at 30 or 40 LOP with 2500 RPM. Agree? Disagree? Bob