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4 hours ago, drstephensugiono said:

Looking and collecting Mooney M20L Porsche PFM Engine Parts, if anyone has or knows of anyone, appreciated. 

439EF379-F3C0-4B7A-B9AD-EC1CCDF44318.jpeg

Your question is the exact question owners were asking 20 years ago. Porsche stopped all support of the engine. There is one M20L that stiLL has the Porsche flying in Canada and one, maybe two in Europe and I think that’s it. Those owners must have bought the last of the engine parts just to keep theirs going until they run out. (Valve spring if I remember correctly was the unobtainium part)

Porsche paid Mooney owners back in the day to buy back the airplanes and they destroyed the engines and even a few of the airplanes, if I remember correctly. Later for the M20L owners that held out, Porsche gave them a cash settlement (I heard $90,000 from one owner and I heard $125,000 from another. I guess it depending on how good you were at holding out.) Some owners  signed off on all liability, pocketed the money and kept flying and some used the money to pay for the STC conversion, when it was available to convert to a IO-550 Continental. (That STC is no longer available). Porsche knew the the 1994 law pass that limited liability to 18 years would take care of them long term - but Volkswagen AG didn’t want the short term exposure of liability and bad press when engines failed. 

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Same reason i passed on a liquid cooled 350hp mooney that was for sale a few years back. When the owner stated the engine manufacturer no longer supported the engine and stopped making parts for it. There would be no way convert it back and thus become a paper weight once a part failed on the engine. 

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3 hours ago, LANCECASPER said:

Your question is the exact question owners were asking 20 years ago. Porsche stopped all support of the engine. There is one M20L that stil has the Porsche flying in Canada and one, maybe two in Europe and I think that’s it. Those owners must have bought the last of the engine parts just to keep theirs going until they run out. (Valve spring if I remember correctly was the unobtainium part)

Porsche paid Mooney owners back in the day to buy back the airplanes and they destroyed the engines and even a few of the airplanes, if I remember correctly. Later for the M20L owners that held out, Porsche gave them a cash settlement (I heard $90,000 from one owner and I heard $125,000 from another. I guess it depending on how good you were at holding out.) Some owners  signed off on all liability, pocketed the money and kept flying and some used the money to pay for the STC conversion, when it was available to convert to a IO-550 Continental. (That STC is no longer available). Porsche knew the the 1994 law pass that limited liability to 18 years would take care of them long term - but Volkswagen AG didn’t want the short term exposure of liability and bad press when engines failed. 

Luckily that airplane had a top overhaul and only has 180 hours since the overhaul so I got some hours left to fly, if the limiting factor is the valve spring then I would have to go the OPP route.

I thought I saw on YouTube that a bunch of these airplanes that’s left flying got together every year?!

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7 hours ago, drstephensugiono said:

Luckily that airplane had a top overhaul and only has 180 hours since the overhaul so I got some hours left to fly, if the limiting factor is the valve spring then I would have to go the OPP route.

I thought I saw on YouTube that a bunch of these airplanes that’s left flying got together every year?!

Mooney SB M20-268 talks about short valve spring life, however the mechanic I talked to back in 2014 said that with the amount of valve spring failures he saw that they should be inspected and most likely replaced every 100 hours. (EDIT: I looked back in my notes and finally they said valves should be adjusted every 25 hours). Of course they aren't available, so that was a moot point and the end of my interest. The valve springs are the tip of the iceberg on that power plant. There's a service bulletin that calls out for the replacement of ignition leads - only problem I'm told is that this was an early electronic ignition hybrid design and no one makes the leads or the distributor. Also there is one prop certified, an MT, and MT does not service them or make blades any more.

Classic cars or motorcycles are fun to have and look at and drive on a sunny day. If you get stalled by the side of the road, AAA will tow you to a garage or back home. Entirely different flying an airplane with an engine that the manufacturer deemed unsafe. You can't pull over to the side of the road and figure it out. I just don't want to see us lose any more Mooney pilots.

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5 hours ago, drstephensugiono said:

Looking and collecting Mooney M20L Porsche PFM Engine Parts, if anyone has or knows of anyone, appreciated. 

439EF379-F3C0-4B7A-B9AD-EC1CCDF44318.jpeg

Dr Stephen, Is that your bird you are collecting parts for?  Tell us more about it. I’ve always wanted a Mooney Mustang….similar situation. Still cool machines. 

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2 hours ago, drstephensugiono said:

I thought I saw on YouTube that a bunch of these airplanes that’s left flying got together every year?!

It looks like there were some European M20K's back in the day converted to Porsche engines. Also Cesnnas and others as well.  But you're right it looks like a handful of long body Mooneys (L) as well.

 

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8 hours ago, drstephensugiono said:

Looking and collecting Mooney M20L Porsche PFM Engine Parts, if anyone has or knows of anyone, appreciated. 

439EF379-F3C0-4B7A-B9AD-EC1CCDF44318.jpeg

I have some PFM Engine gauges somewhere. They have been hanging around my office since we converted a PFM to a Liquid Cooled Rocket back in the late 90's.

I actually have about 20 hours of PFM time. Very cool aircraft. Definitely underpowered, but a joy to fly, way ahead of its time. Bob Kromer told me after my question to him a few months ago (along with 100+ other Mooney fans at the MooneyMax convention) that Porsche asked Mooney to delay the PFM for 6 months in order to develop a higher horsepower Turbo version of the engine for aircraft. He said it would have been the perfect Airplane had they waited. Bob said Mooney refused to wait and came out with the PFM in 1987 before it was ready. He said that was one of two things he regretted in his Mooney career. The other was the '301'. He need to write a mini-novela on that one.

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  • Art
  • Al
  • Lopresti
  • Kromer

 

Four great leaders at Mooney…

Soooo much work to get done…

 

The Cool thing about Mooney engineering…

There aren’t any bad Mooneys… the kind you WANT to avoid…

 

The M20L is the first Long Body… with its lines very traceable to the M20J…

It weighs a little more…. For the areas that got stretched, And it got a little more power….

 

The B model of the M20L… is the M20M TLS, now known as the Bravo… it got a few updates… The TC’d Lycoming engine… and some beefy landing gear to support all of the weight… and a great UL…

 

 

So… focussing on the engine challenge… valve springs are the big issue…. In aviation… the engine runs at a high HP/rpm setting (compared to road use) for hours on end… springs get tired and lose there elasticity… when worked that hard…

Failing springs are probably noticeable in the engine data/monitor… I believe this engine has a pair of springs on each valve… (fuzzy old memory)

The challenge with OPP… we are allowed to make the same springs that are there now… it does not include making a better spring even if we know how…

 

If we want to build a better spring… that is STC writing territory… which is OK too…

 

MS has a few professional STC writers on board… this is a document that gets approved by the FAA…. That includes all the QC steps expected in the process… and methods of testing the new parts to demonstrate that they are working as expected…

The PFM had the magic of simplified engine controls and ignition….   Things we are approaching slowly today… still. 
 

So… if you have a good great mechanic on the team…. This could be a fabulous project!  :)
 

Continue looking for spare parts… and details regarding a missing Mooney shop in FL, a hurricane, and a power saw….
 

Best regards,

-a-

 

http://www.aero-news.net/index.cfm?do=main.textpost&id=1946e114-50b7-4e0f-8ef4-003f1b2afb8e

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As of 2 years ago, there were two of these at Fort Worth Spinks Airport (KFWS).  I saw one of them up close when it was in for maintenance.  Cowling was off.  Interesting to see the Porsche engine in there.  Both planes owned by the same guy.

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On 8/27/2022 at 6:48 AM, mike_elliott said:

There is one on the ramp at ktpf corroding away Atlas aviation would love to see moved since they haven't been pd for tie down in like forever

You mean there is a Porsche-powered Mooney at KTPF? Do you think the guys at Atlas would let us look it over when we come for the Mooney Summit?

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On 8/27/2022 at 4:39 PM, M20Doc said:

I’d always thought that the Eggenfellner Subaru engine conversion held promise , but those turn out to be a bust for most owners who tried them in various homebuilts.

Yea my dad thought so too when he put one in his RV-7. Problem was to get any kind of power you have to turn the engine at 5k or so which sounds and feels like you are driving down a hiway in 2nd gear. 2k rpm sounds nice but 5k sounds straining and wishing you could shift gears. If you brought the rpm’s back the speed dropped off alot. The good news is i could always tell when dad flew a flyby as it sounded like an nascar racing in the sky. 

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Has there ever been a successful engine conversion? I guess it depends on how you measure success, I’m saying roughly airplane engine power and reliability, without too much weight. I think the VW worked out, just very low power?

I thought the GM small block was promising, maybe has gearbox issues?

Met with Trace engines years ago as they wanted us to produce an aircraft with their engine, I kept asking how much, their answer finally was about the same as a turbine.

I thanked them for coming but I honestly didn’t think I could sell a piston for turbine prices no matter how good it was.

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On 8/26/2022 at 4:59 PM, drstephensugiono said:

Luckily that airplane had a top overhaul and only has 180 hours since the overhaul so I got some hours left to fly, if the limiting factor is the valve spring then I would have to go the OPP route.

I thought I saw on YouTube that a bunch of these airplanes that’s left flying got together every year?!

I’m not sure how to make PFM springs via owner-produced.  You’d need the complete specs. . And then make something the same. 

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4 hours ago, jetdriven said:

I’m not sure how to make PFM springs via owner-produced.  You’d need the complete specs. . And then make something the same. 

Byron,

If I had a PFM spring (NOS) (new old stock)

I could take it to an engine spring manufacturer…

  • to define its specs….
  • and cost out their duplication…

Expect there will be…

  • physical measurements of the spring….
  • Material composition….
  • Spring constant…
  • Finishing such as hardening, and other details…

In the off chance….

Does Porsche’s spring manufacturer already make this spring…. By a different name…. 
 

Porsche didn’t want to support the engine…

But their spring guy probably can….?

 

It would be cool to get an improved spring….  But that starts straying from the OPP rule…
 

it might take buying 1k of them… or some large number for a batch….

:)
 

 

More for DSS….
 

interesting project…

start with finding a spring (set) for a PFM….

then find the spring manufacturer of it…

Then find a capable spring manufacturer for it…

 

Kind of like finding a viable method to duplicate the same thing…. And then see if it fits the OPP rule….

May help to hire an aviation attorney to consult with regarding how well this project fits the OPP rule… AOPA has some interesting methods of getting a feel for their legal strength, at low initial costs….

Ask your Mooney mechanic how he feels about this spring in your Mooney’s engine… somebody has to sign the log book for its use….

 

PP thoughts only, not a mechanic or material scientist…. Or aviation attorney….

Best regards,

-a-

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Byron,
If I had a PFM spring (NOS) (new old stock)
I could take it to an engine spring manufacturer…
  • to define its specs….
  • and cost out their duplication…
Expect there will be…
  • physical measurements of the spring….
  • Material composition….
  • Spring constant…
  • Finishing such as hardening, and other details…
In the off chance….
Does Porsche’s spring manufacturer already make this spring…. By a different name…. 
 
Porsche didn’t want to support the engine…
But their spring guy probably can….?
 
It would be cool to get an improved spring….  But that starts straying from the OPP rule…
 
it might take buying 1k of them… or some large number for a batch….

 
 
More for DSS….
 
interesting project…
start with finding a spring (set) for a PFM….
then find the spring manufacturer of it…
Then find a capable spring manufacturer for it…
 
Kind of like finding a viable method to duplicate the same thing…. And then see if it fits the OPP rule….
May help to hire an aviation attorney to consult with regarding how well this project fits the OPP rule… AOPA has some interesting methods of getting a feel for their legal strength, at low initial costs….
Ask your Mooney mechanic how he feels about this spring in your Mooney’s engine… somebody has to sign the log book for its use….
 
PP thoughts only, not a mechanic or material scientist…. Or aviation attorney….
Best regards,
-a-

I’m still in the negotiating process and it’s looking like more of a big risk!
This plane can be flying one moment to a heap of metal in one simple second !


Sent from my iPhone using Tapatalk
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29 minutes ago, drstephensugiono said:


I’m still in the negotiating process and it’s looking like more of a big risk!
This plane can be flying one moment to a heap of metal in one simple second !


Sent from my iPhone using Tapatalk


It is a real risk / reward proposition….

The reward is only interesting if you like to have a plane with a Porsche engine in it…. To go with your other Porsche related machines….

The risk is you have a chance that the engine goes out of spec and becomes unusable as a flying machine…

As the first Long body… it was underpowered… with a power increase coming as a Porsche turbo…. But never came through…

The Bravo was the next LB… with more HP and a turbo….

The ovation was LB#3… 280hp…. More than the Bravo….

The Eagle tried to be an entry level Ovation and was limited by having PFS level of power….

The O3 came along… at 310hp… demonstrating there is a point where you really have enough HP…. :)

 

So… we have kind of touched on the known risks… and only some possible routes to explore a possible solution…

If everything works out with the OPP… you still have the limitations that come with being the first LB….

 

If you want the maximum performance of the LB that has a car connection…. 
 

Find an Ovation or Acclaim that has the BMW design group paint scheme…. Joe Z had one, and added BMW hood logos on it…. It really looked like the plane was a serious BMW aircraft….

There was an orange Long body… OrangeMTL chose the color for its find me ability….

The beemers were much better performers for modern day flying….

The PFM may be great for display and a few flights here and there….

 

If you have an A&P that is also a Porsche-file mechanic… this would be a helpful person to have on board…

But, hunting spring replacement technology and OPP… this is a mechanic with engineering skills….

 

I wonder if Jay Leno has an A&P on his payroll…

Some interesting projects come to fruition when an hour long program is made to sell advertising…. Jay Leno’s garage….

May need a legal teem to keep that project sanitized… for broadcast…. To everyone that wants to take a look…

 

Best regards,

-a- 

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