Throttle, Leaning, and Power Settings

[Mooney810]

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

 

Edited Monday at 09:27 PM by Mooney810

[Hank]

Your F is a little different from my C, but here goes my take on this. Look for other F & J types to have input too.

1) There's no need to lean on runup unless you're at high elevation. I did lean for takeoff in Cody, WY once, but in 17 years that's the only time outside of training that I did so. What does your Owners Manual say? Nevermind the purchased, not made by Mooney checklist.

2) Constant speed props run at a constant speed unless you move the prop lever. Lean by EGT. Lean to touch, richen to smooth is fine.

3) Many people fly their Mooney with IO-360 at WOT, and use RPM and mixture to set power. I have a carb, so can't help you much there, other than to point generally at the Performance Tables in your Owners Manual. 

4) Again, look at your Performance Tables and see what works at various altitudes. I run my O-360 at 2300 below 4000 msl; at 2400 from 4000-7000; and 2500 above 7000.

5) Probably not, if you've only flown it that way a little bit. Talk to who did the overhaul and get their written engine break-in instructions and follow them! Proper break-in is critical!

6) Look at your Performance Tables, it is one of the figures given. Or a modern engine monitor will calculate it for you (is this part of your upcoming avionics install?

7) Can't help you with the turbo.

One last question:  every Mooney I've ever seen or discussed has a redline at 2700 RPM. I hope your mention of runup at 2800 was a typo for 1800? If you've been flying at 2800, there ain't much anyone can do for you.

Good luck, have fun, fly safe and let us know how it goes.

[Mooney810]

2 hours ago, Hank said:

Your F is a little different from my C, but here goes my take on this. Look for other F & J types to have input too.

1) There's no need to lean on runup unless you're at high elevation. I did lean for takeoff in Cody, WY once, but in 17 years that's the only time outside of training that I did so. What does your Owners Manual say? Nevermind the purchased, not made by Mooney checklist.

2) Constant speed props run at a constant speed unless you move the prop lever. Lean by EGT. Lean to touch, richen to smooth is fine.

3) Many people fly their Mooney with IO-360 at WOT, and use RPM and mixture to set power. I have a carb, so can't help you much there, other than to point generally at the Performance Tables in your Owners Manual. 

4) Again, look at your Performance Tables and see what works at various altitudes. I run my O-360 at 2300 below 4000 msl; at 2400 from 4000-7000; and 2500 above 7000.

5) Probably not, if you've only flown it that way a little bit. Talk to who did the overhaul and get their written engine break-in instructions and follow them! Proper break-in is critical!

6) Look at your Performance Tables, it is one of the figures given. Or a modern engine monitor will calculate it for you (is this part of your upcoming avionics install?

7) Can't help you with the turbo.

One last question:  every Mooney I've ever seen or discussed has a redline at 2700 RPM. I hope your mention of runup at 2800 was a typo for 1800? If you've been flying at 2800, there ain't much anyone can do for you.

Good luck, have fun, fly safe and let us know how it goes.

Thanks for the feedback! Yes that was a typo, good catch. Our home base is around 3000' MSL. On the performance tables, I have looked at them, but it brings back around the question of is WOT more efficient and the tables from the 60's may be outdated as stated in the post attached. Looking forward to our new avionics package and engine  monitors as well. Really appreciate the reply. 

 

Thanks 

[Echo]

Turbo guys will chime in.  Does your prop have any RPM limitations?  Mine does for over 2400mp so down lower (I rarely fly below 6500') I can not fly at full throttle.  An engine monitor or fuel flow is a really important instrument of your plane is lacking this I would invest in one.  Enjoy your new plane and ALWAYS point at gear handle and light on short final and verbally say gear down and locked.

[M20E for me]

Buy Mike Busch’s book “Engines” and read it.  Excellent resource and your engine will love you!

[Bolter]

@Mooney810 Was your 15 hours of required transition training for insurance with a Mooney experienced pilot or someone at least used to training beyond typical trainers (like 172)?  What you are describing does not sound like standard practice for our planes.  As @Hank says, leaning during runup is the anomaly event for high altitude airports.  And you would not use that lean setting for takeoff, except for a high altitude airport.  I would expect the CFI with appropriate experience to instruct you differently.  Not trying to be rude, but you may still need proper instruction to manage the plane despite meeting the insurance requirement.  

Where are you located?  Add that to your profile.  Maybe someone in the area can meet with you and discuss it with you in person?  I am in the Seattle area, if that helps.  There are also Mooney instructors on here who may be in your area.  Look at the MAPA pilot proficiency courses as well:

https://www.mooneysafety.com/  (see the bottom of page for dates and locations, next is Henderson, NV)

I had a J with nearly the same engine as your F, namely a 200HP Lycoming 360 with fuel injection.  Standard practice is as you will find on many posts on MS:

1. Full power takeoff, cowl flaps open for cooling
2. RESIST the 25x25 old wives tale.  Climb with full power, full prop, full rich.  Then Leaning as required as you get up in altitude, staying on the rich side.  In cooler weather, put cowl flaps into trail position.
3. Leveling off to cruise, leave WOT, turn back RPM to 2500 or 2600 as you like (I often used 2600, especially at altitudes 8k and over), lean to your preferred setpoint.  I used LOP happily and had an engine monitor to feel confident all cylinders were leaned and at safe temps.  If using single point EGT and CHT, then consider staying ROP unless you are over 10k and confident your are low enough on power to lean without concerns.  Cowl flaps as required for your weather conditions.  

If you are flying relatively low, such as 3k, you may need to throttle back and turn down RPM to keep heat and fuel consupmtion under control. 

And always check your gear is down and say it out loud several times on your approach to landing.  

-dan

[Pinecone]

Turbo is easier.  For take off and climb, all three knobs full forward, cowl flaps open to start.  This works at all density altitudes as the turbo and waste gate maintain the manifold pressure.  You can close the cowl flaps a bit in colder weather, based on CHT.  But most times I just leave them open.

This assumes a proper system with auto waste gate, like the 252 has.  The 231 and aftermarket turbos may require some fine tuning during the take off and climb.

Once you accelerate after level off, adjust MP to desired, then RPM, then lean. 

To learn about leaning, check out the John Deakin Pelican Perch articles on AVWEB.  Best is to take the APS course, available online.   Pretty much all the Mooney POHs are for high speeds (for marketing) and conventional wisdom at the time.  In the 90s, the LOP came forward and is now more the norm.

BTW, for break in, you want high throttle settings for high cylinder pressures to seat the rings.  If you do not run the engine hard enough, you will develop glazed cylinders.  And the only way to deal with that is to pull all the cylinder, re-hone them, and redo the break in.