How do you lean?????????????????????????

[67M20F]

Ok I have heard to do your runup at 1800, and full power, we are only talking about leaning, I fly out of fields that are above 5500 ft, do you lean out at 1800 or 2100 or full power(not sure that I will get more out of the motor but it's been a month since I have flown, much more than I like), I am climbing to 10.5-11.5-12.5K, I have heard to run at peak EGT, heard to run at 50 ROP, heard 50 LOP, Mooney's are slick don't want to ruin all of that.

I only have about 200hrs in airframe, and would like to know what the best way to run this motor and airframe!

NOT A LOP QUESTION! NOT WANTING TO RUN LOP. NEED LOT MORE HRS!!!!!!!!!!!

[N9240M]

Quote: 67M20F

Ok I have heard to do your runup at 1800, and full power, we are only talking about leaning, I fly out of fields that are above 5500 ft, do you lean out at 1800 or 2100 or full power(not sure that I will get more out of the motor but it's been a month since I have flown, much more than I like), I am climbing to 10.5-11.5-12.5K, I have heard to run at peak EGT, heard to run at 50 ROP, heard 50 LOP, Mooney's are slick don't want to ruin all of that.

I only have about 200hrs in airframe, and would like to know what the best way to run this motor and airframe!

NOT A LOP QUESTION! NOT WANTING TO RUN LOP. NEED LOT MORE HRS!!!!!!!!!!!

[Guest Anonymous]

I second looking at the Advanced Pilot Seminar website  on the "Target EGT for runup and climb".  Great stuff that is practical and easy to remember. 

Also, you have an F model (injected, carbureted engines are a lot trickier to run LOP) -- if you don't have an engine analyzer, get one ASAP.  JPI or EI, it really doesn't matter -- either one will save you lots of money and give you the confidence to operate the engine at its peak efficiency.  I know what the owners manual says, but then the owners manual does not assume or even know about the kind of engine information we have available with an engine analyzer.  Learn to use one, and it will pay for itself many times over.

RFB

 

[The-sky-captain]

I'm curious what you guys usually shoot for on the EGT on climbout and cruise? I have been climbing full rich (that how I was instructed) and leaning when I set up in cruise but have began experimenting with it a little bit lately. I usually cruise with the EGT around 1350 to 1400 and the CHT hovering around 360-370.

[mooniac58]

I don't have an analyzer or an EGT that tells me the real temps...I can just find peak and read degrees from that + or -

Regarding Sky Captain's question.  What i do is:

1) For takeoff, full power, full rpm, full rich (from sea lvl)

2) After initial takeoff and around 1000 AGL I back down to 26" and 2600 RPM.

3) Add power to maintain 26" as I climb until WOT

4) Once under 26" MP I lean as needed to remain about 100 ROP through the climb

5) Levling at cruise altitude (typically 7500-8500 MSL) I reduce RPM to 2300, MP is typically around 22" if memory serves me correctly.  I then usually have to lean another turn or so after RPM reduction.  At these altitudes I lean pretty aggressively for the reasons mentioned above - the engine is really not working very hard at 22" and it is unlikely you could harm it with your mixture knob.  I just keep a good eye on CHT's which are always very cool on my bird (320-340ish).

 

[Cruiser]

For takeoff I switch the JPI to EGT only and set it on #1. Full forward(if at a high density airport lean to 1275°F) on the takeoff roll.  Gear up and positive rate reduce RPM to 2600 and trim to 120kts. Maintain 1275 - 1280°F EGT in climb with the mixture control to altitude. Level off, close the cowl flaps, reduce RPM to desired and stabilize, Lean 10° to 20°F LOP depending on altitude. 

[Piloto]

I lean forward on landing for better visibility but lean back in cruise for comfort.

José

[KSMooniac]

You should be taking off and climbing at WOT and FULL RPM, and leaning to maintain sea-level EGT on a reference cylinder...likely 1250-1300 dF.  Anything less than that (or more rich than that) is less efficient and harder on the engine.  Reducing MP or RPM is an old wives tale with no basis in fact for any Mooney engine.

[67M20F]

Ok bad jack bad....

That wasn't as clear as it sounded before I said it in my head.

To clear it up a little, how do you lean at cruse say above 9K, 11K. I have been told to run max egt.

Never fly at sea level so no clue what it peaks at there, and to long of a flight to find out, my max at high alt is around 1475, sounds kinda high to run all day, but I'm probably wrong.

Thanks for the link, now I just need to locate my "target egt" I'm thinking around 1380-1440.

Whatcha think

[airkraft]

67M20F:  We operate at similar density altitudes.  You ask good questions.  I hope I can help. 

Mooniac58 and Cruiser have great operational advice, in my opinion. 

To M58:  I would recommend increasing cruise altitude by several thousand feet if you are going long distances, especially if you are over water.  From my experience, you may pick up a few KTS TAS over 9,500' DA especially if you use 2,500RPM instead of 2,300.

Again, 67M20F:  KSMooniac seems very tech. savy.  Shoot for mid 1,250's hottest EGT on t/o.  Lean 100ish rich during climb.  Find your peak at DA's above 10,000 feet and lean to 50-80 ROP.  [Perhaps, LOP if you have GAMI'S and know what you are doing]. Lean to 80-100 degrees ROP at  DA's where you may achieve more than 75% power.

1,475 seems high, you are right.  I'm normally 1,300 degrees F EGT at our high altitudes.

I'd love to hear from others.  This is a very important issue as to performance, safety and our budgets...

[67M20F]

Thanks airkraft, the reason for asking is I lean to 50-100 ROP, and when I went into annual I found that all my plugs were all most plugged up. My guy told me to run at max egt, thats where I got 1475 or so thats what I will see at around 9.5-12.5K.(yea kinda big range but 9.5 is my low and 12.5 is my high until I go for ox)

If I understand most that at 9.5-12.5 I cant make more than 75%, so in theory I can't blow my motor with the red knob. (I bet I can though, but don't want to) But thinking that way why wouldn't you want max egt?

Side note, during run up I do my mixture at 1800, what you all using, had some instructors say that if you don't lean to max power you can't get max power, others say its hard on the motor and that running up at say 2700 is very bad.

I have read lots on this just looking for what others use, in high DA. In never fly below 2200 and thats probably a dozen flights out of 241hrs last year.

Am I too picky in thinking I can find a better more efficient way to run my motor?

[KSMooniac]

You should lean to a target EGT of 1250-1300 dF for takeoff at any density altitude, and lean in the climb to maintain this target.  As you climb (leave it WOT and max RPM), the EGT will decrease in your normally-aspirated Mooney as the air gets thinner and you make less power.  Every 500 or 1000' simply lean a little more to bring the EGT back to 1250-1300 dF until you reach your cruise altitude.  This method will minimize your time in the climb and not waste fuel while keeping you rich enough to not hurt your engine.  You should NOT try to lean to 100 ROP in the climb...if you do this while you're making a lot of power you could hurt things.  Lean from full rich down to 1250-1300 dF.  If your airplane is setup properly, at sea level on a standard day at full power and full rich you should be in the 1250-1300 dF range.

After climbing while maintaining the target EGT, level off, close cowl flaps, and wait a couple of minutes for the plane to accelerate to max speed, then set cruise RPM and lean to an appropriate value...if above 9k density altitude, then leaning to PEAK EGT is fine, and if your CHTs go warmer than 380 dF then lean a little more to 10-20 LOP.  It is that simple.

If your plugs are fouling, you are running too rich...likely on the ground so you should lean aggressively after startup...to the point that if you apply runup power without enrichening the engine will stumble.  I run LOP everywhere except for takeoff and climbout, and never have fouling problems.

Everyone should take the Advanced Pilot seminar...it is the best money and time you will spend in anything related to aviation.  After taking the course you would have a full understanding of the science behind these techniques and will be able to truly know what is going on when you fiddle with the red knob. 

[fantom]

Excellent advise, Scott.

I keep my cowl flaps in tail much of the time, in cruise. Keeps the CHT a bit cooler, and has zero impact on TAS.

[Parker_Woodruff]

Quote: JimR

I keep my cowl flaps in trail sometimes too, Gary, for the same reasons, also with no observed reduction in cruise speed. The only thing that I don't like about doing this is the rather significant change in cowling air noise that it generates.

[mooniac58]

Quote: Parker_Woodruff

Totally different than my experience.  I see ~10 KTAS by closing my cowl flaps at 6-8000'.

Same here.  There have been a few times I have puzzled over why I am not getting normal cruise speed only to sheepishly realize I failed at my cruise checklist and left the cowl flaps open.  Also, closing these puppies at 140 KTS takes a lot of force, so much I really don't like the feel of it...

Also, if you are not getting good cooling you might consider looking over your baffling.  My mechanic re-cut some new baffling for my bird and it dropped the CHT at least 60 degrees.

At least in my J model it really seems like Mooney got the airflow right in their cowl design, most aircraft run a lot more near the top of the acceptable temp range.

[fantom]

Realize that when we say we're keeping our cowl flaps in trail, that's only slightly open, not completely open.

Good baffling, and not folding your baffling over when putting the cowl on, makes a big difference. I run under 340 on all CHTs at 6-8000 ft, WOT and 2,500 RPM. Usually about 164 KTAS.

[Guest Anonymous]

Quote: 67M20F

Thanks airkraft, the reason for asking is I lean to 50-100 ROP, and when I went into annual I found that all my plugs were all most plugged up. My guy told me to run at max egt, thats where I got 1475 or so thats what I will see at around 9.5-12.5K. 

[eaglebkh]

So how do I know the "target" EGT when my EGT gauge only shows divisions, not actual temps. I'm not really interested in getting an engine analyzer yet (already dumped enough into the panel for the next several years).

[Guest Anonymous]

Quote: eaglebkh

So how do I know the "target" EGT when my EGT gauge only shows divisions, not actual temps. I'm not really interested in getting an engine analyzer yet (already dumped enough into the panel for the next several years).

[KSMooniac]

JPI is/was offering a killer deal on their EDM-700 with Fuel Flow option very recently.  You might consider checking into that...it is a great instrument and I'll never own a plane without one or better.

[eaglebkh]

Quote: SagemGuy

We are starting to go in circles here!

http://www.advancedpilot.com/assist.html -- click on "Target EGT" !

 

[Guest Anonymous]

If the pocketbook won't support a full analyzer right now, there are probably more than a few guys on here that have an old EI EC-1 or equivalent Alcor instrument laying around.  I know I do.

I will take a look next time to the hangar and see if I can find it.

RFB

 

[eaglebkh]

Quote: JimR

So it would seem, at least in your case. If you don't want to spend a couple of AMUs to install a full on engine monitor right now, consider the following. I picked one of these up new on eBay a few years ago for a little over $300 including the probes, and am very pleased with it for basic four probe digital EGT monitoring.

http://aerospacelogic.com/site/dbload.asp?PageId=PROD&Level=2&Inst=EGT-100

 

[mooniac58]

Quote: fantom

Realize that when we say we're keeping our cowl flaps in trail, that's only slightly open, not completely open.

Good baffling, and not folding your baffling over when putting the cowl on, makes a big difference. I run under 340 on all CHTs at 6-8000 ft, WOT and 2,500 RPM. Usually about 164 KTAS.

 Are yours electric cowl flaps?  My manual push rod style ones will not partially open.  After pushing in a bit they slam shut the rest of the way.  I figure it is a tug-of-war between the air rushing down from the cowl trying to keep them open and the air rushing under the aircraft trying to close them.

[alun]

i fly the 78 j and they will stick at half open no problem.