Shadrach

Did you change seats or fly side saddle?

That sucks. Surely Mooney is running PTT, trim and AP disconnect switches through the shaft.

I’m really sorry to learn that you’re still dealing with this.I am baffled. I sent them a working pump which they disassembled and then used parts from both the original pump in your plane and the one that I sent them to get what they told me was a working pump. I logged a few phone calls and several texts walking their tech through trouble shooting and bleeding. He told me the problem was sorted during our final conversation. There are two probable scenarios that explain the symptoms you are experiencing: 1) The hydraulic fluid is contaminated with debris that are preventing the check valves from sealing and fluid Is flowing the wrong direction through the check valves 2) all of the check valve seats need to be recoined to prevent fluid from backflowIng through the check valves. The first thing I would do is tighten the retraction speed screw all the way down. If the flaps stay down under those circumstances, your problem is almost certainly with the retraction circuit valve. If they bleed back up, then fluid is flowing the wrong way through the pump check valves. Feel free to DM me. I am dismayed that you’re still dealing with this..

It would be helpful to know your full power/full rich take off EGTs. Ideally you want to be 250° ROP or more.

I will have to verify the next time I’m at the hanger, but I do not believe that my yolk “rocks“ on the shaft

That is an ugly and catastrophic failure for sure. However, if I’m honest, I think the design and construction of the old welded shaft is superior to the new drilled and bolted version. The new design is definitely less expensive to produce though.

No paint in the nose well well of my 67 Exec.

Hi @Weston, Is this the same M20C that was at a repair station in West Palm Beach back in February?

The problem is that the replacement yoke has no airworthiness documentation. So from a legal standpoint, it's about the same as fitting a set of bicycle handle bars. It could be done and and I can see no reason why it would fall outside the bounds of a minor alteration, but I know of no IA's that would want their name on it. Apparently someone was willing to sign it off. There is a comment from a Piper Cherokee owner that is very pleased with the installation.

I wrote Mr. Fitch this morning outlining my concerns that AD 77-17-04 and the instructions for continued airworthiness therein might contribute to an inspection/maintenance induced failure of the components depicted in the recent Airworthiness Concern Sheet. I would encourage anyone else that has shared these concerns to send a comment. I think that there are more effective and far less invasive ways to mitigate a potential yoke/yoke shaft failure.

Great minds think alike. I will likely share my opinion with Mr. Fitch.

Agreed. Seems unlikely that there was not evidence of impending failure long before it actually failed.

I have theorized for decades that compliance with the AD on the yoke was overly invasive and could create more problems then it solves. I would not be surprised if the initial cracks were caused by trying to remove or reinstall the taper pin.

Good catch. I too have always thought that any sealant/gasket maker on the cylinder flange was a no no. I don’t see how the bolts achieve the proper torque (stretch) with that crap on the flange.

I am pretty sure that the piston, like the cam, relies on splash/spray lubrication from the crank and connecting rods. My guess is that if the piston isn’t getting sufficient “splash” lubrication then it’s not likely that the proximal cam lobes are either.

One could run single mag or adjust the mixture. It was ~10 years ago but my recollection of how it was described to me was that the increase in CHT was still well within the safe operating range.

Yup. Same here. The only time I hit the aft trim stop is when landing with minimum fuel and two up front…and then only on short final…and then it’s only likely because I fly slower approaches than most. Loaded as described I’m crossing the fence at <60KIAS.

Perhaps they fired the marketing manager from 1967…. My standard WOT @2500 and 7500’ shows 187mph in 1967 but only 173 in 1968. Notice the 1967 poh allows for leaning to 100ROP at 76%hp (10.8gph) but in 1968 it’s full rich (14gph). M20F POH cruise data from 1967: M20F POH cruise data from 1968:

I would have zero concerns about issues with tank sealant and o-rings with mogas. Many many STC holders operating in the field with the same gaskets, adhesives and seals. Peterson had to demonstrate compatibility to get the STC approved. Avgas is blended to exceed shelf life specs. Technically, it’s required to meet production standards after 12months in storage. In reality, 10 year old samples that have been properly stored have shown to meet production standards. It’s lasts a long time…

If I go by the 1967 owners manual, my plane is slower than book. If I go by the 1968 owners manual, it's pretty close on speed and efficiency is slightly better because I use more sophisticated leaning practices. Be better if we knew what "about the same" meant. The delta between similar HP models isn't tat far off even if every one is making book speeds.

I agree. The 210 driver I knew was not based at an airport. He had high octane in a tank at a farm strip (this was before Ethanol was pervasive). The Mooney driver that did it was a member here who confessed his sins privately. Another downside mentioned was that he could smell the mogas in the cockpit when he switched tanks.

Not legally but I know of a few scofflaws that have done so. One tank of 100LL and the other 93 mogas. Climb, take-off, and landing on 100LL, cruise on mogas. I was told that switching from 100LL to Mogas increased CHTs by 30-40° all other things being equal. ROI seems low just to save a few bucks. I know of someone who operated an NA C210 this way quite a bit, but for them it was more of a fuel availability issue rather than economics.

Mooney has not been doing “well” for quite some time. I think that they are cash poor. This has led to a more reactionary and transactional approach. They don’t seem to have much of a support strategy beyond “keeping the doors open”. Fabricating obscure parts in low quantities does not serve their current financial situation.

No mention of of GS or wind? Westbound @12,000 often comes with a significantly headwind penalty.

O360s handle mogas just fine. It’s the fuel system design that presents a challenge. Peterson offers a mogas STC for all of the following Lycoming engines, but their approval is airframe dependent. Lycoming 0-145-A1, 0-145-A2, 0-145-B1, 0-145-B2, 0-145-B3, 0-145-C1, 0-145-C2, GO-145-C1, GO-145-C2, GO-145-C3, 0-235-C, 0-235-C1, 0-235-C1B, 0-235-E1, 0-235-E1B, 0-235-C1C, 0-235-C1A, 0-235-H2C, 0-235-C2A, 0-235-E2A, 0-235-E2B, 0-235-L2A, 0-235-L2C, 0-235-M1, 0-235-M2C, 0-235-M3C, 0-235-N2A, 0-235-N2C, 0-235-P1, 0-235-P2A, 0-235-P2C, 0-235-P3C, 0-290-A, 0-290-AP, 0-290-B, 0-290-1, 0-290-C, 0-290-3, 0-290-CP, 0-290-D, 0-290-11, 0-290-D2, 0-290-D2A, 0-290-D2B, 0-290-D2C, 0-320, 0-320-A1A, 0-320-A1B, 0-320-A2A, 0-320-A2B, 0-320-A2C, 0-320-A2D, 0-320-A3A, 0-320-A3B, 0-320-A3C, RAM 160 Conversion, 0-320-B1A, 0-320-B1B, 0-320-B2A, 0-320-B2B, 0-320-B2C, 0-320-B3A, 0-320-B3B, 0-320-B3C, 0-320-C1A, 0-320-C1B, 0-320-C2A, 0-320-C2B, 0-320-C2C, 0-320-C3A, 0-320-C3B, 0-320-C3C, 0-320-D1A, 0-320-D1B, 0-320-D1C, 0-320-D1D, 0-320-D1F, 0-320-D2A, 0-320-D2B, 0-320-D2C, 0-320-D2F, 0-320-D2G, 0-320-D2H, 0-320-D2J, 0-320-D3G, 0-320-E1A, 0-320-E1B, 0-320-E1C, 0-320-E1F, 0-320-E2A, 0-320-E2B, 0-320-E2C, 0-320-E2D, 0-320-E2F, 0-320-E2G, 0-320-E2H, 0-320-E3D, 0-320-E3H, 0-320-E1J, 0-360-B1A, 0-360-B1B, 0-360-B2A, 0-360-B2B, 0-360-D1A, 0-360-D2A, 0-360-D2B, 0-360-A1A, 0-360-A1AD, 0-360-A1D, 0-360-A1F, 0-360-A1F6, 0-360-A1F6D, 0-360-A1H, 0-360-A1H6, 0-360-A1G, 0-360-A1G6, 0-360-A1G6D, 0-360-A1LD, 0-360-A1P, 0-360-A2A, 0-360-A2D, 0-360-A2E, 0-360-A2F, 0-360-A2G, 0-360-A2H, 0-360-A3A, 0-360-A3AD, 0-360-A3D, 0-360-A4A, 0-360-A4AD, 0-360-A4D, 0-360-A4G, 0-360-A4J, 0-360-A4K, 0-360-A4M, 0-360-A4N, 0-360-A5AD, 0-360-C1A, 0-360-C1C, 0-360-C1E, 0-360-C1F, 0-360-C1G, 0-360-C2A, 0-360-C2C, 0-360-C2E, 0-360-C4F, 0-360-C4P, 0-360-F1A6, 0-360-G1A6, 0-360-J2A, H0-360-C1A, 0-435, 0-435-A, 0-435-C1, 0-435-1, 0-435-C1, 0-435-11, 0-435-C2, 0-435-13, 0-540-B1A5, 0-540-B1B5, 0-540-B1D5, 0-540-B2A5, 0-540-B2B5, 0-540-B2C5, 0-540-B4A5, 0-540-B4B5, 0-540-A1A, 0-540-A1A5, 0-540-A1B5, 0-540-A1C5, 0-540-A1D, 0-540-A1D5, 0-540-A2B, 0-540-A3D5, 0-540-A4A5, 0-540-A4B5, 0-540-A4C5, 0-540-A4D5, 0-540-D1A5, 0-540-E4A5, 0-540-E4B5, 0-540-E4C5, 0-540-F1B5, 0-540-G1A5, 0-540-G2A5, 0-540-H1A5, 0-540-H2A5, 0-540-H1A5D, 0-540-H2A5D, 0-540-H1B5D, 0-540-H2B5D, R-680-E3, R-680-E3A, R-680-E3B, R-680-9, R-680-13, R-680-E1, R-680-E2, R-680-6, R-680-B6, R-680-D5, R-680-D6, R-680-B2, R-680-BA, R-680-2, R-680-4, R-680-B4, R-680-B4B, R-680-B4C, R-680-B4D, R-680-B4E, R-680-5, R-680-7, R-680-8, R-680-11, R-680-17, R-680-B5, 0-540-F1B5 (Derated for Robinson), 0-320 Series (Derated for Robinson), 0-360 Series (Derated for Robinson)