NicoN Posted January 21, 2019 Report Share Posted January 21, 2019 (edited) Yesterday, my engine quit when rolling out the rest of the runway after a normal landing. Power was in idle, Mixture in full rich. Restarting was no problem with 2 seconds of primer pump. At the fuel station, the engine was idling with 590RPM, full rich and throttle in idle. Smooth engine-run, no roughness or quitting. I had this behaviour before in summer with pretty high temperatures around 29°C. I was given explanations such as vapor "bubbles" or leaning too aggressive after landing (which I did definitely). But yesterdas it was around 0°C! So bubbles in fuel seem to be not the reason and leaning was definitely not done ! Any explanations? What can I do? Land with low boost pump ON? I learnt to switch on the electric pump on other aircraft types (such as Grumman AA5), but this to have fuel flow in case the mechanical pump quits during a go-around. Edit: The approach was a longer than normal final, with continous power of about 13-14"MAP. Definitevely not an too-high-approach with IDLE power for a longer time. Edited January 21, 2019 by NicoN Quote Link to comment Share on other sites More sharing options...
gsxrpilot Posted January 21, 2019 Report Share Posted January 21, 2019 I’ve been told by DMax and others that this is not uncommon with the Continentals. It happens to me about once every 20 flights or so. I can usually recognize it and catch it with just a bit of throttle. I’ve been doing a lot of power off 180 landings lately and am sure this can’t happen with the wind driving the prop. But on roll out, after slowing a bit, it can happen. Quote Link to comment Share on other sites More sharing options...
jackn Posted January 21, 2019 Report Share Posted January 21, 2019 First things first. Idle should be set to 700 rpm. As was previously mentioned, on roll-out with the wnd pushing the prop, you are probably below your static idle rpm. Simple adjustment to idle, and see if that fixes it before doing a full fuel setup. Quote Link to comment Share on other sites More sharing options...
gsxrpilot Posted January 21, 2019 Report Share Posted January 21, 2019 My fuel system is correct per the book. It’s been checked several times and never needs any adjustment. It’s correct. Regardless this still happens occasionally. Quote Link to comment Share on other sites More sharing options...
Phil EF Posted January 21, 2019 Report Share Posted January 21, 2019 Minimum idle RPM for GB MB and LB is 700 per Continental. 1 Quote Link to comment Share on other sites More sharing options...
cujet Posted January 21, 2019 Report Share Posted January 21, 2019 The idle RPM would be my first guess. However, it's good to remember that low wing aircraft always have low pressure in the fuel lines when the boost pump is off. This can lead to bubbles. Imagine what would happen if there is a tiny leak that introduces air? Quote Link to comment Share on other sites More sharing options...
LANCECASPER Posted January 21, 2019 Report Share Posted January 21, 2019 6 hours ago, NicoN said: Yesterday, my engine quit when rolling out the rest of the runway after a normal landing. Power was in idle, Mixture in full rich. Restarting was no problem with 2 seconds of primer pump. At the fuel station, the engine was idling with 590RPM, full rich and throttle in idle. Smooth engine-run, no roughness or quitting. I had this behaviour before in summer with pretty high temperatures around 29°C. I was given explanations such as vapor "bubbles" or leaning too aggressive after landing (which I did definitely). But yesterdas it was around 0°C! So bubbles in fuel seem to be not the reason and leaning was definitely not done ! Any explanations? What can I do? Land with low boost pump ON? I learnt to switch on the electric pump on other aircraft types (such as Grumman AA5), but this to have fuel flow in case the mechanical pump quits during a go-around. Edit: The approach was a longer than normal final, with continous power of about 13-14"MAP. Definitevely not an too-high-approach with IDLE power for a longer time. That happened to me 3-4 times on an Ovation I had. After I changed the spark plugs it never happened again. (I had Champion massive electrode and went to Tempest massive electrode) Quote Link to comment Share on other sites More sharing options...
DonMuncy Posted January 21, 2019 Report Share Posted January 21, 2019 Continentals will do this if the idle mixture is just a little lean. Check by watching your RPM when pulling to idle cutoff. The RPM should rise 50 to 75 RPM before cutting off. If it does not rise, have your A&P or hangar elf richen the mixture 1/2 screw turn at a time until it does. Quote Link to comment Share on other sites More sharing options...
NicoN Posted January 21, 2019 Author Report Share Posted January 21, 2019 Thank ýou. We have brand-new spark-plugs. I had the engine running with 1000RPM when slowly killing it with the mixture. I am not sure that I have seen a real increase in RPM before the engine stopped. Should this happen in complete Idle? Or with 1000-1100RPM? Quote Link to comment Share on other sites More sharing options...
carusoam Posted January 21, 2019 Report Share Posted January 21, 2019 Nico, 1) Expect moving the engine mixture to Idle cut-off to occur with the throttle pulled out... idling at 700rpm... 2) Often people will set their throttle to 1000 rpm to aid in re-start... Then mixture slowly to ICO to see the rpm rise... 3) I experienced the engine die this summer (once, only one experience...) during taxi, after landing. When checking later, I didn’t get much rpm rise when killing the engine... 4) So At annual this year, I will be checking the idle settings... 5) This is on an IO550(n) 310 hp... 6) I started the engine twice after that... once on the taxiway and once right after shut-down to move the plane again. We were at @orionflt‘s fly-in... Brian gave me some reminders regarding the restart, everything went smoothly as expected... 7) nothing can make you feel more nervous than the engine shutting down on a hot day... in a crowded area... PP observations only. Best regards, -a- Quote Link to comment Share on other sites More sharing options...
jackn Posted January 21, 2019 Report Share Posted January 21, 2019 3 hours ago, gsxrpilot said: My fuel system is correct per the book. It’s been checked several times and never needs any adjustment. It’s correct. Regardless this still happens occasionally. The problem with going by the book, is that the book has your mechanic adjusting high/low fuel pressure while doing ground static run ups. I had a fuel pressure transducer connected to the unmetered fuel pressure line, displayed on the JPI. Then test flew while noting the actual pressures. It took a few iterations to get it dialed in but I’ve never had an issue since. Quote Link to comment Share on other sites More sharing options...
kortopates Posted January 21, 2019 Report Share Posted January 21, 2019 (edited) The Idle mixture adjustment is likely off (slowly leaning to ICO should produce a 20-50 rpm rise before dying) and possibly the low fuel pressure setting is off which should be 6.5-6.7 psi and as stated above the min Idle RPM should be set to 700 rpm - that's 3 separate thing controlling slow idle. But if the low fuel pressure is adjusted at all then the high fuel pressure or max FF must also be re-checked. When this is all properly set up to spec's, the engine won't quit on roll-out! It happened to me recently after I thought I had it dialed in. My wife immediately complained till I re-adjusted and it hasn't happened since. She won't accept that and neither should you! Edited January 21, 2019 by kortopates 2 Quote Link to comment Share on other sites More sharing options...
kortopates Posted January 21, 2019 Report Share Posted January 21, 2019 2 hours ago, jackn said: The problem with going by the book, is that the book has your mechanic adjusting high/low fuel pressure while doing ground static run ups. I had a fuel pressure transducer connected to the unmetered fuel pressure line, displayed on the JPI. Then test flew while noting the actual pressures. It took a few iterations to get it dialed in but I’ve never had an issue since. Hi Jack, JPI provides a differential pressure transducer which is what you want for the metered high pressure and what I have installed in my JPI. That's the important fuel pressure value for all turbo's. Expensive though - near $1K. But in truth, once you have calibrated FF, we're much better setting the high metered FF off the FF value than using the metered fuel pressure - that's really for when we don't have FF or can't trust it for being accurate. The ummetered fuel pressure is only used to set idle pump pressure and for that I just screw in a blue-tooth transducer that is very accurate and get the readings off my iPhone. But agreed, you got to take it up for a lap in the pattern to verify your max FF is properly set for max MAP & RPM. 2 1 Quote Link to comment Share on other sites More sharing options...
kortopates Posted January 21, 2019 Report Share Posted January 21, 2019 3 hours ago, NicoN said: Thank ýou. We have brand-new spark-plugs. I had the engine running with 1000RPM when slowly killing it with the mixture. I am not sure that I have seen a real increase in RPM before the engine stopped. Should this happen in complete Idle? Or with 1000-1100RPM? The test is done at min idle RPM of 700rpm - not 1000rpm. Quote Link to comment Share on other sites More sharing options...
gsxrpilot Posted January 21, 2019 Report Share Posted January 21, 2019 The Idle mixture adjustment is likely off (slowly leaning to ICO should produce a 20-50 rpm rise before dying) and possibly the low fuel pressure setting is off which should be 6.5-6.7 psi and as stated above the min Idle RPM should be set to 700 rpm - that's 3 separate thing controlling slow idle. But if the low fuel pressure is adjusted at all then the high fuel pressure or max FF must also be re-checked. When this is all properly set up to spec's, the engine won't quit on roll-out! It happened to me recently after I thought I had it dialed in. My wife immediately complained till I re-adjusted and it hasn't happened since. She won't accept that and neither should you! I’ll bring you my airplane. 1 Quote Link to comment Share on other sites More sharing options...
kortopates Posted January 21, 2019 Report Share Posted January 21, 2019 6 minutes ago, gsxrpilot said: I’ll bring you my airplane. Sorry I missed you while you came out West and I headed to Mexico! Quote Link to comment Share on other sites More sharing options...
Hank Posted January 22, 2019 Report Share Posted January 22, 2019 1 hour ago, kortopates said: Sorry I missed you while you came out West and I headed to Mexico! Careful, Paul--all these Texans think they are out West. You're gonna bust their bubbles!! 1 Quote Link to comment Share on other sites More sharing options...
DonMuncy Posted January 22, 2019 Report Share Posted January 22, 2019 29 minutes ago, Hank said: Careful, Paul--all these Texans think they are out West. You're gonna bust their bubbles!! Maybe we just think that anyplace west of Texas doesn't matter. Or maybe that is anyplace but Texas 1 Quote Link to comment Share on other sites More sharing options...
Guest Posted January 22, 2019 Report Share Posted January 22, 2019 Has anyone noticed that some K models have firewall bulkhead fittings on the right side of the firewall, I assume they are meant to be able to use engine set up gauges in flight. Clarence Quote Link to comment Share on other sites More sharing options...
LANCECASPER Posted January 23, 2019 Report Share Posted January 23, 2019 On 1/21/2019 at 4:43 AM, NicoN said: Yesterday, my engine quit when rolling out the rest of the runway after a normal landing. Power was in idle, Mixture in full rich. Restarting was no problem with 2 seconds of primer pump. At the fuel station, the engine was idling with 590RPM, full rich and throttle in idle. Smooth engine-run, no roughness or quitting. I had this behaviour before in summer with pretty high temperatures around 29°C. I was given explanations such as vapor "bubbles" or leaning too aggressive after landing (which I did definitely). But yesterdas it was around 0°C! So bubbles in fuel seem to be not the reason and leaning was definitely not done ! Any explanations? What can I do? Land with low boost pump ON? I learnt to switch on the electric pump on other aircraft types (such as Grumman AA5), but this to have fuel flow in case the mechanical pump quits during a go-around. Edit: The approach was a longer than normal final, with continous power of about 13-14"MAP. Definitevely not an too-high-approach with IDLE power for a longer time. You're not the only one whose engine(s) quit after touchdown. https://www.flyingmag.com/all-nippon-787-engines-quit?cmpid=ene20190122&utm_source=internal&utm_medium=email&cid=47340&mid=409734888 Quote Link to comment Share on other sites More sharing options...
Jim F Posted January 23, 2019 Report Share Posted January 23, 2019 5 hours ago, M20Doc said: Has anyone noticed that some K models have firewall bulkhead fittings on the right side of the firewall, I assume they are meant to be able to use engine set up gauges in flight. Clarence Yes mine has them and my guess is that there are for inflight fuel system troubleshooting. Jim Quote Link to comment Share on other sites More sharing options...
Richie the C Posted January 31, 2019 Report Share Posted January 31, 2019 My 231 used to die like that at idle. Changed the fuel pump at last tear down. Never happened again. Quote Link to comment Share on other sites More sharing options...
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