N6018Q

Point taken, (and question answered)

The mechanic who is now working on my plane (the one who did my annual is 150 miles away) seems very convinced that it is an ignition issue rather than a fuel issue. He changed my intake boot, installed an overhauled boost pump from Aeromotors and it is still running rough, though now at lower power settings. He says that his testing of the ignition harness shows that the wires are marginal. Previous mechanic says he tested them with a test box and they all tested good. The problem is still intermittent, sometimes its rough sometimes its smooth. I just purchased a JPI 830 (thanks teejayevans!) and I'm wondering if install it first would help diagnose the problem or if I should wait until the mechanic hopefully figures it out. Stupid question, but would it be worthwhile to install it now or would an install be essentially worthless before the engine is running correctly? What really sucks about this is I'm only about 2 hours by air from Don Maxwell but can't get the plane to him.

Sent you a PM

+1 for Aeromotor. They shipped out an overhauled pump the same day they received mine (Dukes 4140-00-19A). $450 plus shipping both ways

I did. I could stick my finger through some of the holes in the old one

Actually it’s my pump that’s leaking, not my fuel selector. I just noticed while I had some help, that sometimes when my pull ring inside the cockpit is pulled fuel comes out the bottom drain and sometimes it doesn’t. Tried with the selector on both right and left tanks with the same results.

Thanks!

Who overhauls those components? I have a dukes boost pump that’s leaking 2 drops a minute and sometimes fuel comes out the selector when the ring inside is pulled, and sometimes it doesn’t (both tanks)

Are you saying you have a 12v for sale also? If so, I need one for a 1965 M20E and am interested. Thanks

Thanks! First place I checked was Lasar, they are OOS with no ETA. I did find one Top Gun Aviation in Stockton Ca for $265

Need intake duct (between air filter & fuel servo) for M20E 1965 Super 21 (200 HP). LASAR is the only place I've found them listed and they are OOS

I haven't timed it, but it seems it only takes a minute or so for most of the pressure to bleed off normally.

One thing I forgot: the fuel pressure dropped very slowly after engine shutdown. It took about 10 minutes to bleed completely down. Later starts and run ups had normal pressure bleed offs. Don’t know if that means anything....

Many thanks to all who took the time to share your collective expertise. My CFI/mechanic and I tried ,and failed, again this morning to find any sign of roughness or other anomalies. Some asked if fuel pressure, egt, cht changed during the event. It only lasted about 15 seconds but seemed an eternity and we were both scanning every gauge at least twice and could not find anything out of the ordinary. My old JPI only displays 1 temp at a time and the CFI stepped through all 8 temps twice, all were good. Looks like a servo overhaul is in my immediate future. Will report for historical purposes when complete

I do have a fuel flow JPI and a separate JPI engine monitor but they are much older than the 700 model. and yes the fuel flow one is acting weird but I haven’t had time to learn exactly how to program it. I was planning on spending more time with it before flying xcountry. I’m not familiar with sticky valves but will mention it to my mechanic tomorrow. I really appreciate all the ideas

Just had the mags rebuilt last month in Tulsa. We checked those first and they both dropped the expected 75-100 rpm. Brand new spark plugs also. I do have an older JPI with both CHT and EGT monitoring and nothing was out of the ordinary. We will do an air mag check tomorrow. My CFI is also a mechanic and his initial suspect was the fuel servo. We considered injectors but it seems odd that it only happens at 2400 rpm

A little background: I bought a 1966 M20E Super 21 last December. From the complete log books, I know that the engine was replaced in 1978 with a new IO- 360A1B6 and now has ~1050 hrs, with 2222 hours on the airframe. It was flown regularly until 2005 and then appears to have not even had an annual done until it was sold in 2013 to the guy I bought it from. He flew it an average of 10 to 15 hours/year. I know now (from about 30 hours of following this forum) that one of the worst things for these planes is to sit and not fly. My mechanic just completed the first annual which started as soon as I purchased the plane. I spent ~$5000 (which I expected as the last few annuals were basically rubber stamped). Mags rebuilt, new plugs, wires, hoses, etc. My CFI and I have flown a total of 6 hours over the last 2 weeks with no problems. Today we were in the pattern after a 2 hour flight at 2400 rpm when the engine suddenly started backfiring and running very rough. The runway was assured, and as soon as I touched the throttle, it immediately smoothed out. We landed and spent the next 20 minutes running up the engine on the ramp. At least 3 more times, when we hit 2400 rpm, it did the same thing. Both increasing and decreasing rpm immediately solved the issue. We let the engine cool completely and could not duplicate the anomaly again. Any ideas as to what could cause this?

KUXL (Near KLCH)

Thanks. I'll do that. I intend to fly back and forth from northern Oklahoma to southern Louisiana (488nm). Most flights I will have 2 passengers and I know space will be at a premium.

So where is the best place to mount an iPad? I just bought a '65 M20E and only had one flight in it before starting an annual inspection.