M20J not producing thrust

[carusoam]

Hmmm....

Free speed?

Think weight and balance.

1) The tail is responsible for holding the nose up in flight.  To do this, it uses inverted lift...  lift induces drag.

2) WnB can be used in place of some need for inverted lift.

3) Flying around with only front seat occupants can require a fair amount of nose up trim, which equates to a fair amount of drag being added.

4) B can be adjusted towards the back of the envelope by putting some weight in the back.  Reminder: Use a weight and balance calculation, avoid guessing on this one...

5) W is a noticeable trim adjustor, it is less efficient to put a lot of weight in the back seat.  Efficiency improves by putting less weight in the baggage compartment. Efficiency is best improved by adding a small amount of weight in the hat rack following the limitations of the hat rack loading schedule/decal.

6) Doing the WnB work the old fashioned way is sort of free. Doing all the arm calculations can be pretty taxing on the brain.

7) A good compromise, and excellent safety device, is a low cost WnB app available in the App Store of you favorite portable computing device.  Not free, but 'worth it' to many...

8) the best free speed comes from sliding the seats back in cruise!  

9) The O lets the pilot slide way back, and recline...  

10) Other WnB efficiencies come from unloading 40 years worth of old unaccounted for weight left in the form of dirt and unused wiring.

PP thoughts that come to mind...  not a CFI or mechanic.

Best regards,

-a-

[N201MKTurbo]

One way to tell if it is rigging problem or an engine problem is to check the climb rate. The rigging will have a smaller effect on climb rate than cruise speed and engine power will have a greater effect climb rate than cruise speed. 

 

If if you have a decent climb rate, your problem is most likely rigging.

[AaronDC8402]

The fact that the plane is not making book speeds (assuming the OP is reporting TAS and not IAS) and the plane is not making 2700 rpm on roll-out, I'm guessing it's an engine power issue.

You mentioned having the JPI 700. When you start to lean for cruise, do you see any of your EGT's climb earlier than the others. We had a slightly similar issue at one point with our plane. We ended up with one mostly blocked and one partially blocked fuel injectors. Cleaned them up, and everything went back to normal.

 

[cnoe]

Hmmm....
Free speed?
Think weight and balance.
1) The tail is responsible for holding the nose up in flight.  To do this, it uses inverted lift...  lift induces drag.
2) WnB can be used in place of some need for inverted lift.
3) Flying around with only front seat occupants can require a fair amount of nose up trim, which equates to a fair amount of drag being added.
4) B can be adjusted towards the back of the envelope by putting some weight in the back.  Reminder: Use a weight and balance calculation, avoid guessing on this one...
5) W is a noticeable trim adjustor, it is less efficient to put a lot of weight in the back seat.  Efficiency improves by putting less weight in the baggage compartment. Efficiency is best improved by adding a small amount of weight in the hat rack following the limitations of the hat rack loading schedule/decal.
6) Doing the WnB work the old fashioned way is sort of free. Doing all the arm calculations can be pretty taxing on the brain.
7) A good compromise, and excellent safety device, is a low cost WnB app available in the App Store of you favorite portable computing device.  Not free, but 'worth it' to many...
8) the best free speed comes from sliding the seats back in cruise!  
9) The O lets the pilot slide way back, and recline...  
10) Other WnB efficiencies come from unloading 40 years worth of old unaccounted for weight left in the form of dirt and unused wiring.
PP thoughts that come to mind...  not a CFI or mechanic.
Best regards,
-a-

That's probably the best explanation why my speed is the same whether near-empty or loaded up with my thin wife, heavy dog, and baggage to the ceiling. The extra 300# is offset by the rearward shift in CG. I've been using the WnB Pro app for a few years and makes these exercises fun.

I'm still chuckling at the image of you in the left seat, slid all the way back, reclined. Visual scans are highly overrated anyway!


Sent from my iPad using Tapatalk

[gsengle]

On a calm day solo, I can slide my seat all the way back and watch as I gain a knot on the gps...


Sent from my iPhone using Tapatalk

[KLRDMD]

41 minutes ago, gsengle said:

On a calm day solo, I can slide my seat all the way back and watch as I gain a knot on the gps...

In my first Mooney, a "C" model with only the Mooney PC, once nicely trimmed up in level flight I could climb or descend by moving my feet forward or rearward in the foot wells.

[Guitarmaster]

That's probably the best explanation why my speed is the same whether near-empty or loaded up with my thin wife, heavy dog, and baggage to the ceiling. The extra 300# is offset by the rearward shift in CG. I've been using the WnB Pro app for a few years and makes these exercises fun.

I'm still chuckling at the image of you in the left seat, slid all the way back, reclined. Visual scans are highly overrated anyway!


Sent from my iPad using Tapatalk

Especially with ADS-b traffic!!

Sent from my XT1585 using Tapatalk

[jetdriven]

ThereDon't rule out cam and lifters damage. Intake lifters on these engines share the cam lobe, so one trashed lobe will affect two cylinders' intake valves... it was still start and run great but the climb rate won't be as good and it will not lose a lot of speed... it's hard to detect performance until the lobe  is nearly flat.  Then it will make much less than rated horsepower. 

There really is no static RPM adjustment on this airplane.. Mooney SMM  says to take off and fly with the all three knobs full  forward for 5 minutes, pull the prop knob back to a true 2700 RPM verified by an optical tachometer and then set the governor stop screw to match that. 

Speaking of full bore flying, try this. level  off at 1000 feet Leave it full bore,  all three knobs full, perhaps you just do it with the prop setting as above but you should indicate about 190-195 mph. This takes the variables out of the manifold pressure gauge, EGT gage leaning technique prop RPM accuracy etc.

Edited January 23, 2017 by jetdriven

[DXB]

2 hours ago, jetdriven said:

ThereDon't rule out cam and lifters damage. Intake lifters on these engines share the cam lobe, so one trashed lobe will affect two cylinders' intake valves... it was still start and run great but the climb rate won't be as good and it will not lose a lot of speed... it's hard to detect performance until the lobe  is nearly flat.  Then it will make much less than rated horsepower. 

There really is no static RPM adjustment on this airplane.. Mooney SMM  says to take off and fly with the all three knobs full  forward for 5 minutes, pull the prop knob back to a true 2700 RPM verified by an optical tachometer and then set the governor stop screw to match that. 

Speaking of full bore flying, try this. level  off at 1000 feet Leave it full bore,  all three knobs full, perhaps you just do it with the prop setting as above but you should indicate about 190-195 mph. This takes the variables out of the manifold pressure gauge, EGT gage leaning technique prop RPM accuracy etc.

Interesting issue.  I know less than many here, but assuming RPM accuracy and low IAS/TAS are verified, I would think the possibilities are reduced engine power (e.g. low fuel flow, spalled cam, timing off) or bad rigging.  How you definitively detect reduced engine power without a test stand is the question. It will reach 2700 at fine pitch at some point once the takeoff roll is started, even if the engine is weak.   I've read that it should stabilize in the 2650-ish range at full throttle with brakes on and not moving (near sea level and on a standard-ish day). Supposedly this is the only way to verify full power other than on a sophisticated test stand setup.  

Byron -  do you know if this is a legit approach to test engine power? 

[jetdriven]

Static rpm depends on the low pitch stops and the power o the engine. I don't know if a published figure. But I do know that a good clean airplane rigged right and making full power will indicate around 190-195 MPH at 1000' density altitude. If the ailerons and flaps all line up with the wingtip and with each other, and it flies wings level ball centered,  then it's probably rigged okay or enough to not lose more than a couple knots. Anytime you pull the power back you are addding variables. Full throttle 2700 rpm are less variables.  Also, check the muffler for a baffle piece that has broken off and restricting the outlet. 

Check the timing. A dual mag at 20 degrees timing is a slow airplane. I know this from experience. 

[201er]

19 minutes ago, jetdriven said:

Static rpm depends on the low pitch stops and the power o the engine. I don't know if a published figure. But I do know that a good clean airplane rigged right and making full power will indicate around 190-195 MPH at 1000' density altitude.

At what weight? Heavy or light?

[ArtVandelay]

Check the timing. A dual mag at 20 degrees timing is a slow airplane. I know this from experience. 

If the dataplate is stamped 20°, then you legally can't change it, correct?

[Bob_Belville]

On ‎1‎/‎22‎/‎2017 at 9:45 AM, Marcopolo said:

Sfurr,

 

  I am also based near Charlotte (Lincolnton, but live in Mooresville) and I travel to KMRN (Foothills AGL Aviation) 2 to 3 times or more a month.  If you decide to take your J there (and I think it would be a good starting point) let me know if you need any travel assistance.  Taking your Plane to Lynn at AGL or any other Mooney specialist could be the best first step as showing up at an engine shop looking for speed might get you more than you bargained for.  If it is in fact an engine issue or you just want to start there then I agree with DrBill and recommend Triad up in Burlington.   Lynn at AGL works with and has a very good relationship with Triad should he find the need to involve them or require their services.  Using a Mooney specialist to check the normal things, rigging, mag timing, compression, cam wear, etc may save you a bundle over an engine shop.  I took my K to Lynn for a rigging check (just to see, no speed complaints) and he found one aileron and the elevators out of spec, couple of knots...maybe, but having the full up travel of the elevators has definitely changed the feel of my landings.

Again, whatever you decide to do, if you need any assistance please don't hesitate to reach out, even if its just to meet up for a burger.

 

Ron

  

 

On ‎1‎/‎22‎/‎2017 at 11:15 AM, mccdeuce said:

I currently have my 78 J with Lynn at AGL and can say nothing but great things so far.  

+1 to have them take a look at her.

If it is RPM gauge issues I can help you out there. Currently have 2 electronic ones as I contemplate which I like better. 

I've had my E model 5 years. With several 201 type mods it's fairly fast but since Lynn became a MSC and got a set of rigging boards from the factory we found that the elevators, flaps, and one aileron were all out of rig a little. And one mag had gotten to 22 deg BTC (instead of 20). Along with the broken walking beam that we replaced which was allowing the right gear to droop a little when retracted I expect we've improved in flight drag enough to measure in KTAS.

I received a new spinner dome from Hartzell Friday so I'll find out soon. My MS fans will be looking for a pic of the Aspen showing 160 ktas.

[BillC]

On January 21, 2017 at 7:31 PM, gsxrpilot said:

No offense, but nothing here says anything about his expertise with Mooney's. There are lots of experts in a lot of things. And seriously 20,000+ airline pilots are a dime a dozen. But there is a reason that people fly their Mooney's all the way across the country to be touched by Don Maxwell at KGGG or Paul Loewen at 1O2.

The guy who taught me to fly, was and still is my mentor for all things aviation, is a 52,000 hour 747 Captain from PanAm and Braniff. 16,000+ hours as a CFI in the right seat of various Pipers. He did my Mooney check out when I bought my first (700 hours in Mooney's). He knows more about airplanes than anyone I know. But I wouldn't let him evaluate the rigging on my Mooney even if it was free.

20,000 hour airline pilots are a dime a dozen? 52,000 hour pilot? 16,000 hours as a CFI?

Do the math. Part 121 is limited to 1000 hrs. per year. Even if you started flying when your 18 and retire at 65 the most you could fly would be 47,000 hrs. That would NEVER happen. Average yearly flight time is about 600 hours. Plus flying as CFI for 16000 hours? Give me a break. 

  I'm  a retired 747 Captain with 36 years flying 121 and 5 years military pilot and I don't like your comment about a dime a dozen 20,000 hour airline pilots. You don't know what your talking about and sound like a private pilot who has little invested in his education, experience, or manners.

[gsengle]

Please can we keep Mooneyspace civil? The core point is correct which is that years flying airliners doesn't teach you much about rigging a Mooney.

Many of us are accomplished and respected in our chosen careers. And have worked a lot of hours over a lot of years.


Sent from my iPhone using Tapatalk

[kris_adams]

23 minutes ago, BillC said:

20,000 hour airline pilots are a dime a dozen?

I'd bet he's just saying that we all have the 20k hour guy at the airport or are related to one.  My uncle just retired with almost 25k hours.  He's full of good advice as I'm sure you are   Sometimes things just come across harsh when they aren't intended that way.

747 captain...respect.  Would love to hear some stories some day!

[Andy95W]

On 1/22/2017 at 0:00 PM, N201MKTurbo said:

One way to tell if it is rigging problem or an engine problem is to check the climb rate. The rigging will have a smaller effect on climb rate than cruise speed and engine power will have a greater effect climb rate than cruise speed. 

 

If if you have a decent climb rate, your problem is most likely rigging.

+1. And it's also probably the easiest thing to check.

[bradp]

What's your takeoff roll like? Full fuel and gross I'm off by just past the 1000' touchdown markers. Lighter and half tanks it's prior to the touchdown markers. This doesn't vary very much. If it does you have a power problem.


Sent from my iPhone using Tapatalk

[jetdriven]

17 hours ago, teejayevans said:

If the dataplate is stamped 20°, then you legally can't change it, correct?

You can undo the service instruction, SI1325a.  But a bendix dual magneto engine should never be stamped 20 degrees.  They were excluded from that service letter. 

[ArtVandelay]

You can undo the service instruction, SI1325a.  But a bendix dual magneto engine should never be stamped 20 degrees.  They were excluded from that service letter. 

What about electronic ignition, my understanding is they vary timing based on engine sensors? I assume their STC would take preference over stamped data plate.

[jetdriven]

3 hours ago, teejayevans said:

What about electronic ignition, my understanding is they vary timing based on engine sensors? I assume their STC would take preference over stamped data plate.

 There STC for the IO 360 engines will be to set it at 20 or 25° Base timing. All and I mean all IO 360 engines  installed in Mooney airplanes  are legal at 25° of timing.  Some have had SI1325a applied to them and you can reverse that.   I have a letter from Lycoming the grudgingly admits that fact .  The -D engine you cannot apply the SI1325a to it, the others are optional.  It's a moot point regarding electronic ignition  anyway because nobody has a certified solution for that model engine. 

Edited January 24, 2017 by jetdriven

[lukejb]

On January 24, 2017 at 1:04 PM, jetdriven said:

 There STC for the IO 360 engines will be to set it at 20 or 25° Base timing. All and I mean all IO 360 engines  installed in Mooney airplanes  are legal at 25° of timing.  Some have had SI1325a applied to them and you can reverse that.   I have a letter from Lycoming the grudgingly admits that fact .  The -D engine you cannot apply the SI1325a to it, the others are optional.  It's a moot point regarding electronic ignition  anyway because nobody has a certified solution for that model engine. 

I'm interested in learning more about the timing.  So what should the timing be set to in on an io-360 with a dual mag?  I am wondering what my mechanic is setting it to.  At 25 will you get more power than at 20?  I'm pretty clueless when it comes to this and feel like it is something I should know and do want to make sure I am getting optimal performance from my engine.

[cnoe]

I'm interested in learning more about the timing.  So what should the timing be set to in on an io-360 with a dual mag?  I am wondering what my mechanic is setting it to.  At 25 will you get more power than at 20?  I'm pretty clueless when it comes to this and feel like it is something I should know and do want to make sure I am getting optimal performance from my engine.

It almost certainly says 25 on the engine data-plate. Makes a difference too.


Sent from my iPad using Tapatalk

[201er]

9 hours ago, lukejb said:

I'm interested in learning more about the timing.  So what should the timing be set to in on an io-360 with a dual mag?  I am wondering what my mechanic is setting it to.  At 25 will you get more power than at 20?  I'm pretty clueless when it comes to this and feel like it is something I should know and do want to make sure I am getting optimal performance from my engine.

Timing 25, more power but hotter (burden is on you to lean or use cowl flaps for cooling), Timing 20, less power but cooler (you can't get back that extra power when you have sufficient cooling). Lawyers tend to prefer the companies to do the latter because you are less likely to cause damage to the engine or yourself because they took it out of your hands and stifled the engine.

[ArtVandelay]

Timing 25, more power but hotter (burden is on you to lean or use cowl flaps for cooling), Timing 20, less power but cooler (you can't get back that extra power when you have sufficient cooling). Lawyers tend to prefer the companies to do the latter because you are less likely to cause damage to the engine or yourself because they took it out of your hands and stifled the engine.

I like to see the power vs rpm graph of both, I bet the 25° timing helps the high RPMs, but has little effect on lower RPMs, since the pistons are traveling slower, there is more time for the combustion event to complete.