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I was up flying today...

N1049j

N1049j

New member
Taunton
Aircraft Year
1973
Aircraft Type
112/A
Reg Number
N1049J
Serial Number
49
IMG_1381.jpg Nice videos! I was up flying today and thought I would post a picture hoping to get some feedback on settings. I have been running lean of peak and maybe you guys can zoom in on settings and comment!

IMG_1380.jpg
 
N1049j said:
Nice videos! I was up flying today and thought I would post a picture hoping to get some feedback on settings. I have been running lean of peak and maybe you guys can zoom in on settings and comment!
Click to expand...

Hmm. Looks a tad richer than when I'm LOP. At 50 degrees LOP I show about 8-8.5 GPH and EGTs are closer to 1400. Your highest looks like 1359 which would be consistent with a richer mixture.

Interesting your analyzer shows 67% power at 25/25 at 5500'.
 
Tell me more! What should the HP show? Still not sure how to do the lean process! I hear so many different versions! I have been doing when in cruise I do a big pull till engine stumbles and the enrich till it sounds ok. Any sugesstions? What about this pic on my way home at 24/24 IMG_1386.jpg
 
Chuck, What does the 'timer' light indicate / linked to??
 
It is connected to the Electronics International that has a timer with many modes but I use it for a 30 min repeat timer from startup to remind me to switch tanks! Not sure if it is connected to anything else!
 
Here is what mine shows. But I am running rich. Richer than ROP I’m sure.
3919225db76a38b8064b24d3fe0b6378.jpg
 
Jamie, interesting my number 3 cylinder seems to run the hottest! And nice I see you have oil pressure. I just ordered that from them and will install this month during annual! would love to see speed and altitude on that same flight.
 
N1049j said:
Jamie, interesting my number 3 cylinder seems to run the hottest! And nice I see you have oil pressure. I just ordered that from them and will install this month during annual! would love to see speed and altitude on that same flight.
Click to expand...

My number 2 is always significantly hotter than the others. Number 1 being the coolest.

For the oil pressure my IA tapped into the gauge on the lower panel, was a $15 AN fitting.

According to Flight Aware 4,500ft @ 121kts
 
Now that all my flights are not focused on passing a Checkride I am looking forward to getting up and continuing my education and learning more on that and what the plane likes.
 
N1049j said:
Tell me more! What should the HP show? Still not sure how to do the lean process! I hear so many different versions! I have been doing when in cruise I do a big pull till engine stumbles and the enrich till it sounds ok. Any sugesstions? What about this pic on my way home at 24/24
Click to expand...

Well, at 6,000' and Std OAT, 2500 rpm and 23" of MP is 75% power. So you're something past that. Actually excellent that you're able to get 24+ inches MP at 6K.

And for the return picture at 2380/23.5, again assuming std temps, I'd say you're at least at 75% power and you're close to exceeding the maximum recommended MP. Every power chart references "Do not exceed 24 In. Manifold Pressure below 2400 RPM".

Take a look at your power setting charts in the POH. 75% power at 6,000 pressure altitude would be 2,500 rpm and 'full throttle' which should be around 23 inches.

The leaning process varies a bit depending upon the engine monitor setup you have but the general process is the same. Set up a bit ROP and then lean through peak (indicated by your analyzer) and then keep going until you're 50-75 LOP. Here's a summary from our own Bill Bailey who has many, many hours of 112 time and knows of what he speaks:

"Usually use the 75 ROP setting to accelerate on to "the step" before "the big pull" to lean beyond peak. Almost easier to feel the power change than use only the analyzer. The EGT's never exceed 1500 even passing through peak and usually settle in the low 1400's. Cyl's and oil remain relatively cool. Low 320's and 200-208 respectively"
 
Rod, I have not used that procedure and still sorting out all of the versions of what and how to do it! The JPI basically uses a method to find peak and I have been going with the big pull method till I hear and feel it struggling.

Glenn Thanks for the input have not digested your comments yet and will soon.
 
And for the return picture at 2380/23.5, again assuming std temps, I'd say you're at least at 75% power and you're close to exceeding the maximum recommended MP. Every power chart references "Do not exceed 24 In. Manifold Pressure below 2400 RPM".

Thanks for that info Glenn!! What about this big pull method and not looking for Peak?
 
N1049j said:
And for the return picture at 2380/23.5, again assuming std temps, I'd say you're at least at 75% power and you're close to exceeding the maximum recommended MP. Every power chart references "Do not exceed 24 In. Manifold Pressure below 2400 RPM".

Thanks for that info Glenn!! What about this big pull method and not looking for Peak?
Click to expand...


I’m afraid that “over square” admonition is a tired OWT left over from the radial days. Simply untrue. (And I routinely run 29/2200 so I drink my own cool aid). That is not promoting cruising at 85% power for hours on end... just that there are a variety of settings to provide 50%-75% power and that being a slave to the over square OWT is doing a disservice to your operating flexibility. If you consider that every rotation of the crankshaft is creating wear on all the internal parts and the prop, why not achieve your desired power settings at lower RPMs?
 
Hi Chuck,

I fly a normally aspirated 114, so a little different, but the technique should be identical. I also do a big pull, with a little guidance from the fuel flow computer to the expected rate. I have not used the JPI lean find method for some time now. I pull fast enough that I can feel the airplane slow down, and I definitely know I'm on the lean side of peak. I notice that I have to be careful when enrichening the mixture if I pulled too much. It is very sensitive, and a very very small mixture control movement will make a significant jump towards peak, with the resulting warming of CHTs. I find that I generally base my LOP operation on CHT since that is what is most important to me.
 
Are you sure the cylinder numbering matches reality? Are the temps showing numbers 1 and 2 really for cylinders 3 and 4? I would think cylinders 1 and 2 would be closest to the prop, which would be normally cooler than the cylinders in the back. I fly a 114, and my #5 cylinder is the hottest. I run my motor at 1400, but that's a 114 motor.
 
N1049j said:
What about this big pull method and not looking for Peak?
Click to expand...

I have an EI UBG-16 engine monitor that has a Peak Find mode. I set up rich and slowly (maybe taking 30-45 seconds) lean until the UBG16 flashes that I've reached peak. Then I continue to until the UBG16 shows I'm 50-75 lean.

After enough flying you'll pretty much know where you'd be in terms of EGT at your target fuel flow & altitude so understandable that many just lean until they see the 'typical' profile they are looking for. I'll do that sometimes but particularly on longer cross countries I'll use the analyzer to see if I can get it as exact as possible. It's there so why not?
 
ac11 said:
Hi Chuck,

I fly a normally aspirated 114, so a little different, but the technique should be identical. I also do a big pull, with a little guidance from the fuel flow computer to the expected rate. I have not used the JPI lean find method for some time now. I pull fast enough that I can feel the airplane slow down, and I definitely know I'm on the lean side of peak. I notice that I have to be careful when enrichening the mixture if I pulled too much. It is very sensitive, and a very very small mixture control movement will make a significant jump towards peak, with the resulting warming of CHTs. I find that I generally base my LOP operation on CHT since that is what is most important to me.
Click to expand...

I do the same Jeff. I've figured out that, OAT and altitude dependent, I'm around 11.5 - 12.0 GPH at 50-degrees LOP. My CHTs are all in the 330s except #5 which runs in the high 350s.

Mike
 
Reality on cylinder numbers? I don't know assumed when they installed the thing they would have done it properly!!
 
Chuck,

I would not worry about that, they were probably connected correctly on install.

"IF" you wanted, next time you have the upper cowl off, simply disconnect the lead to the cyl probe and see if that shows a fault on the monitor. Don't have to crank it. Disconnecting two would verify.

LOT of variables on cooling, baffling can make a huge difference.
 
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