Mark942

I'll try that this weekend and report back. Thanks

I'll try the vacuum blow test for leaks this weekend. Sounds like a good trick. I assume, I use soapy water and a tooth brush around seals to look for bubbles??

New plugs and wiring harness on order. Talked with A/P today and he is coming over Saturday morning. I want to install new wires and plugs then ground run and see if any difference. If not, I want him to re-time both Mags. Ground run. If no improvement pull both Mags and send to Mag shop for inspection/overhaul. Also want to check if possibility of vibration causing intermittent grounding of one of the Mag P wires. Problem is the same if on Left or Right Mag or Both. That's the plan for now.

On way back to hangar, I tried leaning as far as possible to see if I could find a "sweet" spot. Seemed that running lean helped, but certainly didn't stop backfiring.

No metal in oil. Oil consumption good at about a qt per 8 or 9 hours. Oil analysis at every oil change looks within reasonable range and consistent.

Servo was removed and overhauled at a D&G in Niles, Michigan. Second time, removed and took it up to them and they bench tested it and provided me with all the actual data at no charge. Servo working in spec.

Forgot to mention that I removed the inlet filter, and looked up inside with flashlight as best as I could. Ran engine on tarmac without filter installed just to confirm no difference.

Engine backfires at even low RPMs, below 1000. Just seems to get more violent at higher RPMs.

My A/P repaired it himself at his shop and returned it, and reinstalled. He also set the timing at time of reinstall.

Bendix 200 series -mark

Thanks everyone for your thoughts. I am at work right now and stealing a minute to look at replies. I will respond to some of the questions tonight if at all possible. Sure appreciate the inputs. My last day at "work" is the 22nd and as luck has it, I have been able to rent a heated hanger with a cement floor and nice lighting as of January 1st. Working in a junky 50 year old T-Hangar with a salamander blasting Jet-A fumes makes this a lot more memorable, but looking forward to the new digs. -mark

Thanks Clarence, I'm an electrical engineer, and so always think everything is electrical , having said that I do want to talk with my A/P about simply replacing the plugs and wires (cheap compared to the last few weeks) and maybe he could even find some "loaner" Mags ??? Thanks for your thoughts. -mark

LOW STATIC RPM, Engine Backfiring Background: Mooney 1963, M20E, IO 360-A-1-A with RaJay Normalizing Turbo, 4747 Total Hours, 178 SMOH, plane airworthy but bought in October 2015 to restore better than new as retirement project. 62 hours flown in 24 months since purchase while lots of down time for restoration work such as tank strip and reseal, etc. Chronology of engine problems: Aircraft has performed pretty reliably for having a period of little use for several years. Engine oil analysis at Prebuy=all in normal range, and two subsequent oil analysis the same. First engine issue was a failing left Mag due to an oil seal leak allowing oil into Mag housing (164 SMOH). Repaired and all was well. About 3 months ago, (174 SMOH) on a night takeoff, a glance at engine gauges on the start of the takeoff roll showed RPM 2300, MP 28-29”. Run-up had been normal. I exited onto taxi way, and performed another run-up which again was normal. Did a full power static run-up and only got 2300 RPM. Tried running at 2000 RPM and peak EGT for a minute in the hope that a plug was fouled. Brought RPM down to idle then slowly advanced to full throttle. RPM only 2300 RPM / MP=28. While pulling throttle back, this time the engine began to back fire a few times. Headed for hangar about a half mile away, and by the time I was half way there the engine was VIGOROUSLY backfiring at 1000 RPM. Tried to lean to reduce backfiring but had little effect. Please keep in mind, that until this moment, I had never had a problem with backfiring on this engine. A week later A/P arrived and after a day of checking various things, he felt that the problem was in the fuel system and suspected the fuel injection servo. I removed it and he took it to a repair shop that specializes in overhauling fuel system components. Full overhaul on servo, and 3 weeks later reinstalled and plane ran perfectly. Fast forward 3.7 hours (178 SMOH) spread over 3 flights. Again, a night flight. Everything normal including starting, taxi to runway, run-up Mag check, and Prop check. On take off roll 2300 RPM, 28-29” MP. This time as soon as I brought throttle back, the engine started backfiring. Tried to clear plugs by 2000 RPM leaning, but as soon as throttle reduced, backfiring begins and continues. Back to hangar, and now A/P has spent 4 days with me spending much more time than that in between his visits, doing the manual labor. All intake gaskets and seals replaced. Fuel sumps double checked for water or sediment, lines purged, screens removed and cleaned, lines removed from fuel divider and fuel pumped into measured container and timed. All 4 lines equal. Fuel pressure on electric pump alone about 10 PSI. Fuel pressure with engine pump at full throttle 25-30 range and doesn't change with or without electric pump on. Fuel Servo removed and taken for bench flow testing with no issues. Fuel divider removed, inspected by A/P, cleaned, and new diaphragm installed just because we had one. Turbo has not been engaged at all in the past 10 hours of flight. On the ground, we have moved the turbo control lever and verified that the exterior turbo lever arm is going from stop to stop. Compression checks are always in the range of 73 to 78. We have checked compression several times. A/P has rotated prop by hand and felt for proper compression feel and sound. He has inspected the valves with a bore scope and sees nothing unusual. I have asked about the Prop governor and he says the blade angle looks proper with engine off, and the prop would not cause the backfiring. He has 40+ years of experience working for several shops including a period at Purdue University and has owned his own shop for 25+ years. He says this has him stumped. My A/P is reaching out to discuss with Lycoming Engines, and a couple other A/P shops. The plane was scheduled to go into an avionics shop today for the beginning of several upgrades including an Avidyne IFD 550, but that has now been rescheduled for January at the earliest. Any thoughts on contacting SAVVY aircraft maintenance management. I know it is “after the fact” but has anyone had experience with them being able to pinpoint a problem where an experienced A/P is stumped?? BTW, I only have an original analog EGT on cylinder #3. No fancy engine monitor for help. All other crappy original Money analog engine gauges are in normal range. Ref: Major Overhaul in November 2001 at (4569 TTAF). Hours flown per year: Year Hrs 2002 22 (22 SMOH) (4591 TT) 2003 29 (51 SMOH) (4620 TT) 2004 16 (67 SMOH) (4636 TT) 2005 17 (80 SMOH) (4649 TT) 2006 7 (87 SMOH) (4656 TT) 2007 5 (92 SMOH) (4661 TT) 2008 4 (96 SMOH) (4665 TT) 2009 10 (106 SMOH) (4675 TT) 2010 2 (108 SMOH) (4677 TT) 2011 1 (109 SMOH) (4678 TT) 2012 0 (109 SMOH) (4678 TT) 2013 0 (109 SMOH) (4678 TT) 2014 0 (109 SMOH) (4678 TT) 2015 2 (111 SMOH) (4680 TT) Purchased plane in late October, 2015 2016 43 (154 SMOH) (4723 TT) 2017 24 (178 SMOH) (4747 TT) Waiting for a solution to problem Left Mag Repaired 4733 Fuel Injector Overhauled 4743 Second issue +3.7 Thanks, -mark

Andy, I discussed with my wife tonight and she suggested that I should wait until I am finished with the interior make over and then get the belts to match since we are still flip flopping on the color scheme. Guess i will pass after all, but thanks for getting back to me. -mark

I have a 64E without shoulder harnesses and would like to upgrade to belts with harnesses. How would the shoulder strap attach?? If they will work in a 64E then I too am interested, but only if Dennis and Greg pass. -mark

Thanks for all the great detail. I find that I am relearning how to get my hand to bend into unnatural shapes until it cramps up and I drop the screw for the umptenith time . Reminds me of my young days when I spent more time under my 396SS than in it. I do enjoy working on the plane though, and the details you share will help me a lot. Thanks,

Hi this is Mark, I have a 64 M20E that I bought last year and love it. I am slowly ($$$) trying to restore it with a lot of TLC and willing to work next to my kind ole A/P. Looking to upgrade interior. I have owned a machine shop and pretty good with my hands and not afraid of work, but want it to turn out nice. Opinions on buying interior "kits" and from where; as well as I would like to upgrade to seats with head rests before I recover them. Also I will be attempting to reseal tanks this spring prior to painting next winter. Was told by paint shop that I should replace donuts in gear prior to repaint and tank reseal. How do I determine if donuts should be replaced?? My A/P says there should be a way to measure height?? but he is not versed in it, and also how do I get use of the special wrench?? Suggestions please, -mark

To Mike, (rangermb), Thanks for the chance to go up with you yesterday. As I posted on here earlier, I went ahead and made the plunge and bought my first Mooney (yet to be delivered) but after a chance to fly with you, Mike, I am certain I have made a good decision. Your explanations and walk through of how and why and your own experience of transition from a Cherokee to a Mooney really helps. Thanks so much for the generosity of your time and the chance to fly your Money with you for a bit. Just wanted to let everyone know how much I appreciated your coming to Warsaw to give me my first taste of the Mooney experience. -mark

Thanks everyone for your thoughts and your encouragement. I think I need to get my wife to sit in one. She is the one who complains about being claustrophobic. She always wants an isle seat on airliners. She was dead set against a Van's RV until I got her to actually sit in one up at OshGosh. It was a RV7A and she loved it. We didn't go up, but we did shut the bubble and she said she was just fine in it. I think the bubble helped with that. I think it is a bit of a roasting oven in the sunlight, but then I am really a winter person. I will show her these posts tonight. Thanks again, -mark

Hi All, I have about 550 hours and had IFR rating 24 years ago. Stopped flying when I sold my business (used to use it to visit customers and suppliers) and family and life took over. Now, at 62 my wife told me I had to have a hobby if I ever wanted to retire. All I do is work. So, I started flying again. VFR and have picked up a few refresher hours under the hood. Love to fly IFR, and do cross countries and can now afford something a bit more than a 140, but not a lot. Looking at older M20's as a good deal for the money. BUT, I have owned a Cherokee 140, and a Beech Sundowner for many years, flown 172's, 150's, and Diamond DA20's and 40's and even a Van's RV7A. Never even sat in a Mooney. Kind of scary to put down a deposit on a plane a thousand miles away pending a pre-buy when I might hate the thing???? I live near Warsaw, Indiana KASW. Anyone willing to give me a ride. I would cover expenses of course. Thanks, -mark