Power settings

[Patrick Horan]

I know there are countless of pages regarding power setting and how to run this engine. But when I try any of these power settings. I can't get anywhere near the fuel burn for that particular power. I must be doing something wrong and not leaning properly. I'm afraid to lean this airplane (ROP or LOP) because when I start to. My engine gets ridiculously hot like 413°. It seems like I can only fly this engine at full rich when I'm above 14,000. I just did a long cross-country from Utah to New York. I'm tried different settings and the results are not what I was expecting.

 

I should note that I am still learning this plane

Edited July 13 by Patrick Horan

[N201MKTurbo]

What plane do you have? Your tag says you have an M20C, but you are showing a monitor for a six cylinder 28 volt airplane.

[N201MKTurbo]

Running 82% power in cruise will run hot.

[Rick Junkin]

At that power setting on a M20M you should be able to set around 18GPH ROP and keep the temps in check. Have you tried opening your cowl flaps in cruise? Some folk have reported needing them half way open in cruise for adequate CHT control. Your CHTs are relatively even so probably not a baffling issue.

Your TIT doesn’t look correct to me, as compared to the individual EGTs. Generally the TIT runs about 50 degrees higher than the average of the individual EGTs on my engine. Yours looks about 100 degrees lower than where I’d expect it to be, which may indicate a tired and failing TIT probe. They last 200-300 hours in my experience.

If you want to try something different and are willing to run at a lower power setting, try 30/2200 and ~16.5GPH. That’s a ROP setting at about 75%. Adjust the cowl flaps to see if you can keep the CHTs in the 360-380 range. TIT will be in the mid 1500s. If you want to try LOP, pull the fuel flow back to 13.2GPH and see if your engine will run ok there. That’s 70%. You should be able to keep CHTs in the 330-350 range and the TIT under 1600.

You’re having temp control issues so I recommend moving to a lower power setting for your experimenting to see if you can get things under control, and then work up to a higher setting as you learn how your engine performs and what it needs to keep the temps where you want them.

Cheers,
Junkman

[Patrick Horan]

58 minutes ago, N201MKTurbo said:

Running 82% power in cruise will run hot.

That percent power on the JPI is inaccurate

[Patrick Horan]

1 hour ago, N201MKTurbo said:

What plane do you have? Your tag says you have an M20C, but you are showing a monitor for a six cylinder 28 volt airplane.

Mooney M20M Bravo

[Patrick Horan]

2 minutes ago, Rick Junkin said:

At that power setting on a M20M you should be able to set around 18GPH ROP and keep the temps in check. Have you tried opening your cowl flaps in cruise? Some folk have reported needing them half way open in cruise for adequate CHT control. Your CHTs are relatively even so probably not a baffling issue.

Your TIT doesn’t look correct to me, as compared to the individual EGTs. Generally the TIT runs about 50 degrees higher than the average of the individual EGTs on my engine. Yours looks about 100 degrees lower than where I’d expect it to be, which may indicate a tired and failing TIT probe. They last 200-300 hours in my experience.

If you want to try something different and are willing to run at a lower power setting, try 30/2200 and ~16.5GPH. That’s a ROP setting at about 75%. Adjust the cowl flaps to see if you can keep the CHTs in the 360-380 range. TIT will be in the mid 1500s. If you want to try LOP, pull the fuel flow back to 13.2GPH and see if your engine will run ok there. That’s 70%. You should be able to keep CHTs in the 330-350 range and the TIT under 1600.

You’re having temp control issues so I recommend moving to a lower power setting for your experimenting to see if you can get things under control, and then work up to a higher setting as you learn how your engine performs and what it needs to keep the temps where you want them.

Cheers,
Junkman

Thank you so much ill try that now

[FoxMike]

I would suggest you lean to the TIT.  I lean the engine to 1600dF and doing so have not had an exhaust crack.  The picture shows your are 1378dF.  If you leaned using TIT 1600dF I am sure the fuel flow will drop to a more acceptable level.  I am an old guy so I am not in a big rush so I cruise around 2250/27 and FF is around 16Gal/hour.  Gas mileage is around 10 NM/gal.  I have tried different power settings and settled on this because engine temps seem reasonable.  Oil temp always seems high which I think results from Mooney adding the wet head without replacing the oil cooler with a larger one.  The wet head is a good thing as it picks up lots of heat and adds measurably to the oil temp.

[Patrick Horan]

22 minutes ago, FoxMike said:

I would suggest you lean to the TIT.  I lean the engine to 1600dF and doing so have not had an exhaust crack.  The picture shows your are 1378dF.  If you leaned using TIT 1600dF I am sure the fuel flow will drop to a more acceptable level.  I am an old guy so I am not in a big rush so I cruise around 2250/27 and FF is around 16Gal/hour.  Gas mileage is around 10 NM/gal.  I have tried different power settings and settled on this because engine temps seem reasonable.  Oil temp always seems high which I think results from Mooney adding the wet head without replacing the oil cooler with a larger one.  The wet head is a good thing as it picks up lots of heat and adds measurably to the oil temp.

I tried leaning to TIT, but for my engine, my Cylinders get way to hot. I'm at 412 when I lean for tit

[LANCECASPER]

Patrick,

Do you have a picture of your engine without the cowling?

I am guessing your baffles seals are "lazy" and are letting air escape out the top rear of the engine compartment. Especially on this engine, the seals need to be tight and let no air out the back. This forces the air down over the cooling fins on the cylinders, which has to happen on an air cooled engine.

On the last M20M I had I bought the Gee Bee baffle seals and replaced the factory seals. Immediately I had a minimum of 20 degrees difference at a low power setting (25/2400rpm/1600 tit) and almost 30 degrees at a higher setting (29/2400rpm/1600 tit).

Here's an article worth reading: https://www.aviationconsumer.com/maintenance/engine-baffle-seals-worth-replacing/

 

Here's one of the many posts on here about Baffle Seals:

 

Since the cylinders on this engine are nearly $4500 each, doing the baffle seals to keep them cool is so much cheaper than a top end overhaul. 

https://www.airpowerinc.com/05k22177

[Patrick Horan]

1 hour ago, LANCECASPER said:

Patrick,

Do you have a picture of your engine without the cowling?

I am guessing your baffles seals are "lazy" and are letting air escape out the top rear of the engine compartment. Especially on this engine, the seals need to be tight and let no air out the back. This forces the air down over the cooling fins on the cylinders, which has to happen on an air cooled engine.

On the last M20M I had I bought the Gee Bee baffle seals and replaced the factory seals. Immediately I had a minimum of 20 degrees difference at a low power setting (25/2400rpm/1600 tit) and almost 30 degrees at a higher setting (29/2400rpm/1600 tit).

Here's an article worth reading: https://www.aviationconsumer.com/maintenance/engine-baffle-seals-worth-replacing/

 

Here's one of the many posts on here about Baffle Seals:

 

Since the cylinders on this engine are nearly $4000 each, doing the baffle seals to keep them cool is so much cheaper than a top end overhaul. 

Thanks Lance. I'm doing an oil change on the plane now. I'll send you a picture of what they look like

 

[PilotX]

+1 for baffle seals.

[LANCECASPER]

6 hours ago, Patrick Horan said:

Thanks Lance. I'm doing an oil change on the plane now. I'll send you a picture of what they look like

 

Your baffle seals in that picture look good, but other potential leaks around the engine - sent you some other possibilities for high temps

[Fritz1]

The factory baffles have lots of leaky spots even when in good shape, around alternators, oil cooler, starter, anywhere with light shining through is a leak, If the rubber baffles are fine check if metal baffles between cylinders are installed correctly, check ignition timing 20 before TDC, your CHTs are at least 20 dF higher than what I see at 30/23 18.5 gph

[Patrick Horan]

I sent the photo to Lance, but I might aswell send the picture of the baffles here. One thing I learned today after I changed my oil. I might not have installed/positioned the baffles correctly when I took the cowling off previously 

[Fritz1]

Baffles look good, maybe small kink in front of pilot, not sure if there is a leak where throttle cable goes through firewall, all small leaks add up

[Jetpilot86]

On 7/13/2024 at 10:41 AM, Patrick Horan said:

That percent power on the JPI is inaccurate

Based on the engine chart, it‘s about 79% Try the 30/22 number @Rick Junkin is suggesting. I have a hard time keeping #6 below 380° at 31/22, roughly the same as 29/24, at any FF unless the CF’s are full open. I can do 30/22 with 1/2 CF. 
 

I’ve had Maxwell install new GeeBee’s, added FineWires, and still fight temps when it’s ISA+20 out. 

[affricate]

On 7/13/2024 at 10:43 AM, Patrick Horan said:

I know there are countless of pages regarding power setting and how to run this engine. But when I try any of these power settings. I can't get anywhere near the fuel burn for that particular power. I must be doing something wrong and not leaning properly. I'm afraid to lean this airplane (ROP or LOP) because when I start to. My engine gets ridiculously hot like 413°. It seems like I can only fly this engine at full rich when I'm above 14,000. I just did a long cross-country from Utah to New York. I'm tried different settings and the results are not what I was expecting.

 

I should note that I am still learning this plane

Hey Patrick, my Bravo is located at Tucson International.  I'm familiar with these settings. I'm headed back from Ohio tomorrow, and I'm always back and forth between Louisiana and Ohio.  Hit me up if you need anything. These are awesome planes!

[Patrick Horan]

So I tried 30" and 22rpm, I was at 16,500 yesterday flying home and tried ROP and my Cylinder #1 was at 408 and cylinder #3 was at 414. My TIT was about 1430s. I have a two TIT gauges. One for the JPI, the other is the standard analog gauge.

I tried lower power settings at lower altitudes and higher altitude and this engine won't run ROP at all. Even down low, my Cylinders are high and my TIT is low. With and extremely high fuel burn. Maybe my injectors should get cleaned? They are gami.

[Patrick Horan]

I should have mentioned, at the power setting 30/22 I was able to fly LOP nicely. I lose about 13 knots but I'm burning 15 gallons and TIT of 1600 and cylinders at 373 the hottest.

[LANCECASPER]

On 7/18/2024 at 8:23 AM, Patrick Horan said:

So I tried 30" and 22rpm, I was at 16,500 yesterday flying home and tried ROP and my Cylinder #1 was at 408 and cylinder #3 was at 414. My TIT was about 1430s. I have a two TIT gauges. One for the JPI, the other is the standard analog gauge.

I tried lower power settings at lower altitudes and higher altitude and this engine won't run ROP at all. Even down low, my Cylinders are high and my TIT is low. With and extremely high fuel burn. Maybe my injectors should get cleaned? They are gami.

Something is definitely off if you can't run ROP.

When you reach cruise and start setting your cruise numbers, 29"/ 2400 as an example, when you lean back to 1600 TIT ROP where do your CHTs settle in at? Then what was your fuel flow?

Great you can run LOP since there have only been a few people that ever were able to make that happen on that engine. But I would get the ROP figured out first, mainly to make sure your gauges are showing numbers comparable to what thers are under the same parameters. Power settings, then lean to 1600. See where you are. At 29/24 1600 you'll probably be in the 18-19 gallons per hours area. Those are known settings, so now figuring out what your CHTs are with cowl flaps (1) full open, (2) 1/2 open and (3) full closed will give you something to compare with everyone else with that engine and it will be easier to figure out where to go next.

BTW, it looks like you got your Altitude hold issue resolved - not even you can hold altitude like this :    https://he.flightaware.com/live/flight/N9153Z/history/20240717/1101Z/KMGJ/KAWG

[FoxMike]

You might try swapping your CHT probes around to prove they are reasonably accurate.  Number 3 cylinder normally has two probes bayonet and gasket.  Which are you relying on in flight?  It takes some time and effort to swap the bayonet on #1 with another but the high temp might move.  Proving the accuracy of the sensors is what I would try next.  

[affricate]

On 7/18/2024 at 6:23 AM, Patrick Horan said:

So I tried 30" and 22rpm, I was at 16,500 yesterday flying home and tried ROP and my Cylinder #1 was at 408 and cylinder #3 was at 414. My TIT was about 1430s. I have a two TIT gauges. One for the JPI, the other is the standard analog gauge.

I tried lower power settings at lower altitudes and higher altitude and this engine won't run ROP at all. Even down low, my Cylinders are high and my TIT is low. With and extremely high fuel burn. Maybe my injectors should get cleaned? They are gami.

I think something could be off. I was 16,5 from Moore County TX after a fuel stop from Ohio to Tucson and 27 / 2250 TIT 1580 with the flaps cracked open slightly with my number one at 385. I Even backed off to 24 / 2250 because of the good speed I was achieving.

Even on climb outs in AZ heat, I usually  climb 700 fpm, bringing the engine MP to 32-33 after take off and still keep the #1 under 400. 

I try to keep TIT 1585 and below on this engine. 

[EricJ]

On 7/13/2024 at 7:42 PM, Patrick Horan said:

I sent the photo to Lance, but I might aswell send the picture of the baffles here. One thing I learned today after I changed my oil. I might not have installed/positioned the baffles correctly when I took the cowling off previously 

I was thinking, "That's a fancy motor for an M20C!"

You should update your profile deets! 

[Patrick Horan]

8 minutes ago, EricJ said:

I was thinking, "That's a fancy motor for an M20C!"

You should update your profile deets! 

You are definitely right!