Engine stalls during turns while taxiing

[David Mazer]

An IA I know has been asked by a 252 owner about a rough engine while turing to the right while taxiing.  The owner claims he was told a rough engine or engine stalling during taxi turns was/is a common problem with Mooneys.  I've never experienced it and haven't noticed any comments about it on this forum.

 

Are any of you long experienced Mooney owners aware of any such phenomenom, the cause and solution if it exists?

Thanks.

[mikesalman]

If my engine ran rough or stalled during taxi I am not leaving the ground.

[Piloto]

Switch fuel tanks. Sounds like low fuel or water in the tanks.

Jose

[FlyDave]

If it was an IA/A&P that told the 252 owner then it sounds like a lazy 3rd party IA/A&P to me.....(was that too hard to follow?)

[PTK]

An IA I know has been asked by a 252 owner about a rough engine while turing to the right while taxiing. The owner claims he was told a rough engine or engine stalling during taxi turns was/is a common problem with Mooneys. I've never experienced it and haven't noticed any comments about it on this forum.

Are any of you long experienced Mooney owners aware of any such phenomenom, the cause and solution if it exists?

Thanks.

How about a rough engine in the air when banking to the right?

Did this IA have an opinion about that too!? :-)

[Jsavage3]

This airplane should be grounded immediately until the issue is resolved!

 

Wire chaffing in the ignition system perhaps?

[David Mazer]

First, the IA in no way thought this was normal or made sense.  His experience with Mooneys is growing but not tremendous and asked if I had ever heard of it or if I knew where I could ask.

 

Now that the IA's reputation has been defended, no, there is no issue in the air.  There is no indication there is water in either tank and it is always on turning in the same direction, right.  Fuel quantity is not an issue.  I don't know if it depends on the tank being used and I will pass on that thought.

 

Thanks for the feedback.  Any other possibilities?  Anybody ever heard of this before?

[1964-M20E]

Instead of bashing the MX let’s try to help out here.

 

Think about it rough engine only when turning to the right.  Now all of our directional controls extend downward from the rudder pedals and wiring is above the controls.  I assuming that the yolk is stationary.  So the mere act of pushing on the pedals does not seem to be the culprit as far as  rubbing against any wires.

 

What about your knees under the dash are they hitting anything while taxing?

If you switch mags does this cause the same thing at the same RPM?

What about mixture are you leaning during taxi or not?

What is the RPM range where this happens?

How did the nose gear and tube structure look at the last annual?

[orionflt]

Check to see if it is happening on both tanks or just one, also check the tank vents. Then try it with the electric fuel pump running and see if it stumbles. That being said if none of that makes a difference try it on one mag at a time and see what you get, if one of the mags are grounding during the turn this will let you know what one it is. The problem is either going to be in the mag or the fuel system, once you isolate which one the trouble shooting will become easier.

Brian

[Marauder]

I would also keep the fuel injection system in mind while going through the trouble shooting.

[Skywarrior]

"The owner claims he was told a rough engine or engine stalling during taxi turns was/is a common problem with Mooneys."

 

Reminds me of the "Tractor Incident" Seinfeld episode.

[PTK]

"...I assuming that the yolk is stationary...."  

 

 

I wouldn't "assuming" that! Those yolks are elusive characters!

 

[John Pleisse]

Sediment or ball problem in fuel bowel?

[1964-M20E]

I wouldn't "assuming" that! Those yolks are elusive characters!

 

images (2).jpg

OK so I used the wrong term whip we with  silly string.

[fantom]

If it's only happening when the plane turns right, I suggest the pilots political leanings be checked.

The 252 may just be compensating

[jackn]

Actually, Mine used to do the same thing (not while turning to the right, think that's just a coincidence). My previous plane's O-360 ground ops SOP was to lean till RPM drop, enrichen a little. The TSIO360-SB does not run well on the ground at low idle <900 rpm fully leaned out. At Sea Level, I lean just a little, I have had no problem with plug fouling.

[Joe Zuffoletto]

My 1998 Encore would glug-glug through turns in either direction on the ground, then run nice and smooth while going straight. I was told my several experts it was normal for that engine/airframe, and I flew the plane without incident for 11 years. My Acclaim doesn't do it, though.

[29-0363]

I had an identical problem on my 1998 Ovation with the Continental IO-550G. It began with a drop in RPM in right turns and until I solved it I would add a tiny bit of throttle before turning to keep it running. The final straw was a night landing on YBBN RWY 19 - the engine quit and I had to do a hot start and vacate before the following 737 did a GA.

I spoke with the factory and was told to check and adjust the fuel pressures at both idle and high RPM. They also referred me to the engine handbook. The pressures were checked, found to be out of adjustment, and once recalibrated the problem was solved.

[Oscar Avalle]

This airplane should be grounded immediately until the issue is resolved!

 

Wire chaffing in the ignition system perhaps?

Agree, don't leave the ground!

[29-0363]

This is the reply from Wed Dale of MAC after I contacted him in Nov 2002 about the engine stalling while turning.

 

Good Morning. Your fuel flow should be set up to the following specs:

 

    1. Warm engine to 160-180 F oil temp.

 

    2. Adjust low unmetered fuel pressure to 8.0 to 10.0 PSI. We find they do best at the high end of the spec.

 

The MaintenanceManual calls for 9.0 PSI, but that setting can leave the engine lean, just as you are experiencing.

 

    3.Set the high pressure to 24.5 to 25.0 Gallons per hour at 2500 rpm and full throttle using the onboard gauges. 

 

      This adjustment often times affects the low end setting, so it will have to be rechecked as well.

 

    4. Adjust the idle mixture to get a 50 to 75 RPM rise at 750 RPM initial setting.

   

    5.Adjust the idle to 750 RPM.

 

    6. After any adjustment, lightly tap on the component which was adjusted. This helps the adjusted pieces seat into their new position, and a very important step in the process.

 

These engines like to run a little rich at idle, as most Continental engines do. You may want to use Chapter 71-00-51of the M20R manual and TCM SID97-3 Setup Procedures as a guideline, but the specs I have provided work well at our Service Center.

[29-0363]

This is the reply from Wed Dale of MAC after I contacted him about the engine stalling while turning. These notes are specific to the Continental IO-550-G in the Ovation.

 

Good Morning. Your fuel flow should be set up to the following specs:

 

    1. Warm engine to 160-180 F oil temp.

 

    2. Adjust low unmetered fuel pressure to 8.0 to 10.0 PSI. We find they do best at the high end of the spec.

 

         The MaintenanceManual calls for 9.0 PSI, but that setting can leave the engine lean, just as you are experiencing.

 

    3.Set the high pressure to 24.5 to 25.0 Gallons per hour at 2500 rpm and full throttle using the onboard gauges. 

 

       This adjustment often times affects the low end setting, so it will have to be rechecked as well.

 

    4. Adjust the idle mixture to get a 50 to 75 RPM rise at 750 RPM initial setting.

   

    5.Adjust the idle to 750 RPM.

 

    6. After any adjustment, lightly tap on the component which was adjusted.  

   

        This helps the adjusted pieces seat into their new position, and a very important step in the process.

 

These engines like to run a little rich at idle, as most Continental engines do. You may want to use Chapter 71-00-51of the M20R manual and TCM SID97-3 Setup Procedures as a guideline, but the specs I have provided work well at our Service Center.

[FAST FLIGHT OPTIONS LLC]

If my engine ran rough or stalled during taxi I am not leaving the ground.

[FAST FLIGHT OPTIONS LLC]

+1

[David Mazer]

Thanks for the information guys.  Very helpful.  I am passing it on as you get it to me.

[jackn]

I spoke with the factory and was told to check and adjust the fuel pressures at both idle and high RPM. They also referred me to the engine handbook. The pressures were checked, found to be out of adjustment, and once recalibrated the problem was solved.

Very good point. If the fuel system is set up properly, there is no need to lean on taxi. Also, I set my full power fuel flow a bit on the rich side. This gives me the ability to use a lower power setting while in a cruise climb. This saves a little gas and wear on the turbo.