aajones5 Posted January 1, 2017 Report Share Posted January 1, 2017 Hello Everyone, I'm a new owner of a '68 Ranger as well as a fairly new pilot (a year and a half and 250hrs), I've got my instrument rating and am currently working on my commercial license working towards CFI. I'm always trying to learn more to run my Mooney more efficiently but there's a lot I don't know so I was hoping to get some advice from experienced owners as well as use this to ask some questions I have about it. Quote Link to comment Share on other sites More sharing options...
aajones5 Posted January 1, 2017 Author Report Share Posted January 1, 2017 Does anyone know the reason why the POH says not to run the RPMs between 2000-2200 I believe, I've tried to look into this but can't find an answer anywhere Quote Link to comment Share on other sites More sharing options...
Hank Posted January 1, 2017 Report Share Posted January 1, 2017 Welcome! As you learn to fly her, you'll love your plane. Start with the guidance in the Owners Manual. Quote Link to comment Share on other sites More sharing options...
Hank Posted January 1, 2017 Report Share Posted January 1, 2017 Just now, aajones5 said: Does anyone know the reason why the POH says not to run the RPMs between 2000-2200 I believe, I've tried to look into this but can't find an answer anywhere It's harmonics between the engine and prop. Vibration can do bad things . . . Quote Link to comment Share on other sites More sharing options...
aajones5 Posted January 1, 2017 Author Report Share Posted January 1, 2017 Thank you Hank, yes I didn't really appreciate the plane until I bought it and got used to it, going 140knots and burning 8.2 gal/hr isn't bad. I have an issue with my carb heat whenever I turn it on especially coming in to land the engine starts to sound really rough so I limit when I run it to only when I think carb ice is possible. I'm just wondering if yours does the same thing. Quote Link to comment Share on other sites More sharing options...
gsxrpilot Posted January 1, 2017 Report Share Posted January 1, 2017 I logged 400 hours in a C and never once used the Carb heat other than during run up to check that it worked. 1 Quote Link to comment Share on other sites More sharing options...
rbridges Posted January 1, 2017 Report Share Posted January 1, 2017 1 minute ago, gsxrpilot said: I logged 400 hours in a C and never once used the Carb heat other than during run up to check that it worked. same here 1 Quote Link to comment Share on other sites More sharing options...
Mooneymite Posted January 1, 2017 Report Share Posted January 1, 2017 Using carb heat raises the temperature of the intake air and thus effectively lowers the air density so your engine runs rich. Lean the mixture a bit and it will smooth right out. Everything is working as it should. Indications of carb ice can be very subtle with a constant speed prop. Carb heat is cheap insurance. The POH recommends use under certain circumstances unless you have a carb temp indicator. 1 Quote Link to comment Share on other sites More sharing options...
aajones5 Posted January 1, 2017 Author Report Share Posted January 1, 2017 Well that's really great to know yeah I had read about the leaning when using carb heat but I haven't had a chance to test it out yet. Speaking of leaning, I read an article that said you should lean pretty aggressively on the ground to improve engine life and I usually take off with the mixture out about 2 fingers width for best power. What do y'all think about it and what are your leaning procedures Quote Link to comment Share on other sites More sharing options...
carusoam Posted January 1, 2017 Report Share Posted January 1, 2017 I got a decade and about 1000 hours of M20C time. Some of the best hours I have had on and off the planet... Two things I picked up by speaking with people at the factory... 1) get the owner's manual for the year that matches your plane...1968 2) get the POH for the most recent version of your plane...1976 or 7? One keeps you legal for the ramp check. The other is full of performance data not available in the earlier versions. Additional things of interest are.., 3) A parts manual for the M20C. 4) A maintenance manual for the M20C. If I were buying an M20C, I would want... 5) an engine monitor with a carb temp gauge installed. The carb has the place to mount the TC already. Having the gauge allows you to know carb heat is really working and how much carb heat is needed. Excess carb heat robs power. Too little builds an ice block that can be hard to overcome... 6) an iPad... good for checking MS, and a great place to store all kinds nav data like WingX, works good with adsb in for weather updates and some traffic... 7) a WAAS caliber GPS. To go along with all the nav radios... 8) reliable fuel floats feeding a digital display. 9) a FF display integrated with distance and flight plan info from the GPS. 10) a handful of dollars to spend on training. Transition Training at first and MAPA PPP training after that... These are the top 10 things that come to the mind of a PP, not a CFI.... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
cctsurf Posted January 1, 2017 Report Share Posted January 1, 2017 ALWAYS take off with full rich, you are risking detonation by taking off without full rich mixture unless you are above 3,000 ft density altitude. Lycoming now says to lean to best power mixture for ground operations, including run up. Mike Busch has an excellent webinar on leaning (actually 2, there is an advanced leaning webinar as well). https://youtu.be/_VfiPuheeGw 2 Quote Link to comment Share on other sites More sharing options...
DXB Posted January 2, 2017 Report Share Posted January 2, 2017 2 hours ago, aajones5 said: Thank you Hank, yes I didn't really appreciate the plane until I bought it and got used to it, going 140knots and burning 8.2 gal/hr isn't bad. I have an issue with my carb heat whenever I turn it on especially coming in to land the engine starts to sound really rough so I limit when I run it to only when I think carb ice is possible. I'm just wondering if yours does the same thing. I have a '68 C too - congrats BTW. Great bird, consider posting some pix. I've never had this issue unless carb heat is on when I go idle on short final, so I usually turn it off with my final GUMPS recheck just before that. A side benefit of doing that is no chance of forgeting to turn it off for a go around. I do have it full on from just prior to reducing power for descent, as per the POH. I do lean aggressively in cruise and never enrich during descent after the power reduction, so maybe that helps prevent issues also. As an aside, a carb temp gauge is a great and inexpensive thing. It lets me use a bit of carb heat in cruise to keep temps in the high 40s- pretty much takes carb ice off the table without sacrificing power. Also supposedly it can improve mixture distribution. Carb Temp is too dynamic to follow during descent to watch the gauge constantly, so I just pull it full on. 1 Quote Link to comment Share on other sites More sharing options...
DXB Posted January 2, 2017 Report Share Posted January 2, 2017 Also it just occurred to me that if the problem is mainly at close to idle, you may want to have your idle mixture checked. Look for transient rpm rise of about 50 when you pull mixture to idle cutoff when shutting down. If it's much more than that, you want the idle mixture leaned on the carb - it has to be adjusted in unison with the throttle idle position on the carb in a stepwise trial and error process. 1 Quote Link to comment Share on other sites More sharing options...
carusoam Posted January 2, 2017 Report Share Posted January 2, 2017 Dev has become an O360 Master! Best regards, -a- 1 Quote Link to comment Share on other sites More sharing options...
Hank Posted January 2, 2017 Report Share Posted January 2, 2017 Jonesy-- Anthony made a good list, but I would reorder them as #1, 2, 3, 4 and 10 first, the rest are "nice to have"s. I have #7 and half of #5 (carb temp gage only). I lean aggressively on the ground, enough so that advancing throttle to taxi uphill or from grass to pavement makes the engine stumble if I don't enrich some. Guarantees I can't take off like that. Also keeps lead buildup to a minimum and leads to smoother mag checks. I may burn off a mag once a year, sometimes. Always take off full rich. If you want to lean in the climb, read up on Target EGT. Since I always descend power on, I don't mess with carb heat. I push the yoke for 500 fpm and trim for hands off, whether I'm descending from 3000 msl lunch run or 10,000 msl cruise. As I descend, periodically reduce throttle to cruise setting, then push mixture forward to cruise EGT value. Then I level off at TPA and reduce throttle for 90mph downwind with Takeoff Flaps. Leaning is pretty simple, find peak and enrich; I go 50°F rich. Some people say that fuel economy can be improved by backing off the throttle some to create turbulence in the carburetor for better fuel atomization, and adding some carb heat. My C would not run smoothly LOP no matter what I did until I spent two annuals resurrecting the doghouse (lots of sheet metal work), and redid the carb heat box when a joint on the flapper failed (replaced the missing gasket then, too; no idea when it disappeared). Now I can run 25°LOP, but generally don't since I don't have an engine monitor (don't really have panel space for one, and the Carb temp gage is pretty small). Unlike our fuel-injected brethren, I don't run WOT, either. Up high when traveling, I pull the throttle back just enough to make the MP needle move (for atomization as above), set 2500 RPM and lean away. The key number for our engines is 47, to get 65% power. Sometimes I use this rule, sometimes I use setting from the Performance tables. Key number is MP + RPM; so 20" / 2500 is 20 + 25 = 45, so you can lean wherever and however you want fairly safely. This is what I use around 9500 / 10,000 msl. Try ROP, Peak and LOP up high and see which combination of speed and fuel burn works best for you. Sorry to be so verbose . . . Have a great New Year, and fly safe! 1 Quote Link to comment Share on other sites More sharing options...
aajones5 Posted January 2, 2017 Author Report Share Posted January 2, 2017 2 hours ago, carusoam said: I got a decade and about 1000 hours of M20C time. Some of the best hours I have had on and off the planet... Two things I picked up by speaking with people at the factory... 1) get the owner's manual for the year that matches your plane...1968 2) get the POH for the most recent version of your plane...1976 or 7? One keeps you legal for the ramp check. The other is full of performance data not available in the earlier versions. Additional things of interest are.., 3) A parts manual for the M20C. 4) A maintenance manual for the M20C. If I were buying an M20C, I would want... 5) an engine monitor with a carb temp gauge installed. The carb has the place to mount the TC already. Having the gauge allows you to know carb heat is really working and how much carb heat is needed. Excess carb heat robs power. Too little builds an ice block that can be hard to overcome... 6) an iPad... good for checking MS, and a great place to store all kinds nav data like WingX, works good with adsb in for weather updates and some traffic... 7) a WAAS caliber GPS. To go along with all the nav radios... 8) reliable fuel floats feeding a digital display. 9) a FF display integrated with distance and flight plan info from the GPS. 10) a handful of dollars to spend on training. Transition Training at first and MAPA PPP training after that... These are the top 10 things that come to the mind of a PP, not a CFI.... Best regards, -a- I've got most of these covered; I never thought about getting a recent version of the POH I'll look into that and I'm currently getting everything set up to get an EDM 900 set up so that I'll have very precise engine measurements, very excited about that. 1 Quote Link to comment Share on other sites More sharing options...
tigers2007 Posted January 2, 2017 Report Share Posted January 2, 2017 Does anyone know the reason why the POH says not to run the RPMs between 2000-2200 I believe, I've tried to look into this but can't find an answer anywhere Correct me if I'm wrong, aren't RPMs in this range prohibited at or above 75% power??Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
aajones5 Posted January 2, 2017 Author Report Share Posted January 2, 2017 14 minutes ago, Hank said: Jonesy-- Anthony made a good list, but I would reorder them as #1, 2, 3, 4 and 10 first, the rest are "nice to have"s. I have #7 and half of #5 (carb temp gage only). I lean aggressively on the ground, enough so that advancing throttle to taxi uphill or from grass to pavement makes the engine stumble if I don't enrich some. Guarantees I can't take off like that. Also keeps lead buildup to a minimum and leads to smoother mag checks. I may burn off a mag once a year, sometimes. Always take off full rich. If you want to lean in the climb, read up on Target EGT. Since I always descend power on, I don't mess with carb heat. I push the yoke for 500 fpm and trim for hands off, whether I'm descending from 3000 msl lunch run or 10,000 msl cruise. As I descend, periodically reduce throttle to cruise setting, then push mixture forward to cruise EGT value. Then I level off at TPA and reduce throttle for 90mph downwind with Takeoff Flaps. Leaning is pretty simple, find peak and enrich; I go 50°F rich. Some people say that fuel economy can be improved by backing off the throttle some to create turbulence in the carburetor for better fuel atomization, and adding some carb heat. My C would not run smoothly LOP no matter what I did until I spent two annuals resurrecting the doghouse (lots of sheet metal work), and redid the carb heat box when a joint on the flapper failed (replaced the missing gasket then, too; no idea when it disappeared). Now I can run 25°LOP, but generally don't since I don't have an engine monitor (don't really have panel space for one, and the Carb temp gage is pretty small). Unlike our fuel-injected brethren, I don't run WOT, either. Up high when traveling, I pull the throttle back just enough to make the MP needle move (for atomization as above), set 2500 RPM and lean away. The key number for our engines is 47, to get 65% power. Sometimes I use this rule, sometimes I use setting from the Performance tables. Key number is MP + RPM; so 20" / 2500 is 20 + 25 = 45, so you can lean wherever and however you want fairly safely. This is what I use around 9500 / 10,000 msl. Try ROP, Peak and LOP up high and see which combination of speed and fuel burn works best for you. Sorry to be so verbose . . . Have a great New Year, and fly safe! Hank, I always descend power on too I like to get good ground speed in the descent, even in perfectly smooth air I start to get nervous around 170mph and pull the throttle back do you normally go faster in the descent or where do you push it. I usually lean for 50F rich as well it seems to be a good compromise between best power and best econ. I've never heard of pulling the throttle slightly to create turbulence, I had read that its most efficient to run full throttle so in cruise I always did full throttle and 2500 rpm. Also my instructor told me to prevent against shock cooling to pull the throttle back 1-2" every 1000 feet or so, I always just pulled it back when I was getting too fast. Thanks for all the info! Quote Link to comment Share on other sites More sharing options...
carusoam Posted January 2, 2017 Report Share Posted January 2, 2017 Tigers, Depends on your combination of airframe, and propellor. Year of construction may also change some of the finer details. One thing for sure, don't use another plane's limitations while flying yours. At least, not without solid reasoning. And/or approval. The protections that are put in place by the various zones on the tach are not feelable by a human being. Broken welds on the engine mount are probably a result of these limitations... my C liberated a lower engine mount bolt by breaking welds. Flying around with three bolts instead of four holding the engine on... three tiny bolts... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
aajones5 Posted January 2, 2017 Author Report Share Posted January 2, 2017 7 minutes ago, tigers2007 said: Correct me if I'm wrong, aren't RPMs in this range prohibited at or above 75% power?? Sent from my iPhone using Tapatalk That sounds logical since I usually get into that range once I pull the throttle back to slow down for landing Quote Link to comment Share on other sites More sharing options...
carusoam Posted January 2, 2017 Report Share Posted January 2, 2017 Check the phraseology on that... it could be avoid 'continuous operation' no power limitation given... There is plenty of discussion around here on what continuous operation means... and some good advice how people transition through that range... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
carusoam Posted January 2, 2017 Report Share Posted January 2, 2017 Hank is an Overall Engineering M20C genius... We have a Swiss M20C around here for some international M20C experience. He has a pretty nicely updated panel as well... And a couple of Pro pilots with military backgrounds flying around in M20Cs as well... Some of the sharpest knives in the drawer are flying M20Cs... Go MS! Best regards, -a- 1 Quote Link to comment Share on other sites More sharing options...
tigers2007 Posted January 2, 2017 Report Share Posted January 2, 2017 I've never heard of pulling the throttle slightly to create turbulence, I had read that its most efficient to run full throttle so in cruise I always did full throttle and 2500 rpm. If you have a carb, it is my understanding that at full throttle an "enriching circuit" is active within the carb to further cool the heads during full powered modes such as takeoff and ascent - guys does this sound correct? I thought there was a special fuel jet that blows more fuel into the carb at full throttle. Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
carusoam Posted January 2, 2017 Report Share Posted January 2, 2017 Yes, there is a secondary fuel jet that is opened at FT. It takes pretty good instrumentation to see it in operation. FF and EGTs... or just an eyeball to see how it works while on the ground. Check out the controls on the carb... throttle and mixture. Best regards, -a- Quote Link to comment Share on other sites More sharing options...
Hank Posted January 2, 2017 Report Share Posted January 2, 2017 16 minutes ago, tigers2007 said: If you have a carb, it is my understanding that at full throttle an "enriching circuit" is active within the carb to further cool the heads during full powered modes such as takeoff and ascent - guys does this sound correct? I thought there was a special fuel jet that blows more fuel into the carb at full throttle. Sent from my iPhone using Tapatalk That's the other half of why I pull the throttle back slightly in cruise--it shuts off the enrichment fuel flow, and cocks the throttle in the carb, hopefully creating turbulence to better atomize the fuel. Partial carb heat may also help, but I've given up experimenting with that. Note that this is only for O-360 engines with a carburetor. Quote Link to comment Share on other sites More sharing options...
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