Happy 231 owner coming up on TBO looking at '262' upgrade

[Geoff]

Hi guys. As title says I'm happy with my airframe and looking at options for engine at TBO.

Considering MB swap. Does this require STC? Who would you recommend do the work? Any pitfalls? Can I go all the way to SB?

Would enjoy better cooling and second alternator. Single alternator on 231 isa weakness IMO.

[231LV]

HI Geoff

I, too, own a 231 with a runout GB engine...looked into this several years ago...the 262 upgrade was doable through Mooney Mart or one of those shops that I'm not sure are even in business any more. Maybe a 262 owner can chime in here....the only way to get a K to become a 252 requires the original airframe be serialed from 25-1000 through 25 -1230...otherwise no go. If you have one of those serialed airframes, you can purchase the required kits for the gross weight increase and double alternators for around $36k...this info is several years old and predates the latest Mooney shut down and subsequent purchase by the new owners so I'm not even sure this is still available and I'm willing to bet it is a lot more money....after all was said and done, I decided it would be a smarter deal to sell my airframe and runout engine, combine the proceeds with my engine reserve and buy a nice 252

[Mike A]

What is actually required in getting an STC approved by the FAA?  Is it feasible for an owner (or a few) to work through the process on their own?  Since it has been done before, can any of that certification information or data be used for a new STC?

 

I believe the 262 conversion STC is locked up in a legal hell probably never to return....

[Geoff]

Is there not way to get a FSDO field approval of the engine/cowling substitution?  Really just a FWF swap of a proven engine/airframe combination.

[231LV]

...no...It's a major alteration....gross weight increase and electrical....just getting a field approval from the local FSDO for a change in my landing light configuration was a pain...

[231LV]

What is actually required in getting an STC approved by the FAA?  Is it feasible for an owner (or a few) to work through the process on their own?  Since it has been done before, can any of that certification information or data be used for a new STC?

 

I believe the 262 conversion STC is locked up in a legal hell probably never to return....

I suspect if it was financially feasible, it would have been done by now...many Mooney shops specialize in parts (LASAR and Top Gun) so pursuing this would be logical if they saw a potential benefit

[Mike A]

I suspect if it was financially feasible, it would have been done by now...many Mooney shops specialize in parts (LASAR and Top Gun) so pursuing this would be logical if they saw a potential benefit

 

I could believe that it is not financially feasible for a company that is wanting to make money to do it, the demand isn't there to justify the costs.  However what about a group of 5-10 owners who are interested in the upgrade deciding on one plane to be the test bed, splitting the testing and analysis costs and getting an equal share of the ownership of the STC?  If someone told me that I could spend a few AMU's now to be able to do the upgrade when I am ready (or sell my STC to a willing participant) I would be very interested.  The owner of the certification airplane would have to be on the hook for the engine and modification charges by themselves though...

[231LV]

I could believe that it is not financially feasible for a company that is wanting to make money to do it, the demand isn't there to justify the costs.  However what about a group of 5-10 owners who are interested in the upgrade deciding on one plane to be the test bed, splitting the testing and analysis costs and getting an equal share of the ownership of the STC?  If someone told me that I could spend a few AMU's now to be able to do the upgrade when I am ready (or sell my STC to a willing participant) I would be very interested.  The owner of the certification airplane would have to be on the hook for the engine and modification charges by themselves though...

well...for me, as I looked at the financial feasibility of it, the smart deal would be to sell my airframe with runout engine and combine my engine reserve to buy a nice 252...I'm guessing many would come to the same conclusion

[Mike A]

well...for me, as I looked at the financial feasibility of it, the smart deal would be to sell my airframe with runout engine and combine my engine reserve to buy a nice 252...I'm guessing many would come to the same conclusion

 

Disagree.  I watch the trends of 231/252's on Controller.  If you have a 231, especially with a run out -GB or -LB engine, you are at best getting $90k with flawless paint and interior and upgraded avionics.  Assuming you planned for a reman engine, you will have +/- $35k in your reserve.  Combining those together (approximately $125k) it will buy you either:

1) 262 Trophy Conversion with mid time engine, damage history, and original avionics 

2) 252 with mid time engine and original avionics

 

 

Add $10k to that and you can get a 252 with run-out engine and upgraded avionics.  Add $15k more ($150k total) to that to find the low end of the Rocket conversions and decently maintained 252's.  Don't forget to add $8-$10k for sales tax for any of the previously mentioned purchases (plus broker fees if applicable).

 

Hopefully, by the time that I reach the point of doing the overhaul on the engine (in 5+ years), my 231 will have the avionics that I want and installed, interior that I want and installed, paint I want and had done, and I will know the maintenance and behavior of the plane front and back.  The only thing I would like to change is the engine type.  I'm pretty sure that's the situation that OP is in currently.

 

A reman -MB engine from Continental is $55k.  Add $5k for removal/install, $5k for the STC work (guesstimate), and $10k for the required modifications and you can get yourself a 12V, firewall forward 252 on an airframe that you know and have customized to your liking for about the price of someone else's decent 252 that you don't really know the history of.  

 

I'd take the conversion.  All.  Day.  Long.

 

But my question was what is involved with obtaining an STC?  If the -MB conversion isn't to your liking, how about getting your own Rocket STC (or buying it from them)?  If you aren't changing anything beyond the firewall (minus placards and misc other stuff), how involved can it really be?  How about getting an STC for a turbo-diesel engine when they come out?

 

The 262 Trophy Conversion was $69k - $79k, but that included a lot of interior work as well (http://www.mooneymart.com/modifications/100MMA.php)

[carusoam]

Call the good folks at Rocket Engineering...?

No funny law suits or business crushing hurricanes.

They have expertise in Mooneys and that type of STC business.

See if enough time has passed to make business sense to upgrade your machines.

Best regards,

-a-

[231LV]

Pristine 252 will likely go for $180ish....my runout 231 with engine reserve ($58 k last I checked )won't get me there.....hence I'm still driving my runout 231....since I dont

Disagree.  I watch the trends of 231/252's on Controller.  If you have a 231, especially with a run out -GB or -LB engine, you are at best getting $90k with flawless paint and interior and upgraded avionics.  Assuming you planned for a reman engine, you will have +/- $35k in your reserve.  Combining those together (approximately $125k) it will buy you either:

1) 262 Trophy Conversion with mid time engine, damage history, and original avionics 

2) 252 with mid time engine and original avionics

 

 

Add $10k to that and you can get a 252 with run-out engine and upgraded avionics.  Add $15k more ($150k total) to that to find the low end of the Rocket conversions and decently maintained 252's.  Don't forget to add $8-$10k for sales tax for any of the previously mentioned purchases (plus broker fees if applicable).

 

Hopefully, by the time that I reach the point of doing the overhaul on the engine (in 5+ years), my 231 will have the avionics that I want and installed, interior that I want and installed, paint I want and had done, and I will know the maintenance and behavior of the plane front and back.  The only thing I would like to change is the engine type.  I'm pretty sure that's the situation that OP is in currently.

 

A reman -MB engine from Continental is $55k.  Add $5k for removal/install, $5k for the STC work (guesstimate), and $10k for the required modifications and you can get yourself a 12V, firewall forward 252 on an airframe that you know and have customized to your liking for about the price of someone else's decent 252 that you don't really know the history of.  

 

I'd take the conversion.  All.  Day.  Long.

 

But my question was what is involved with obtaining an STC?  If the -MB conversion isn't to your liking, how about getting your own Rocket STC (or buying it from them)?  If you aren't changing anything beyond the firewall (minus placards and misc other stuff), how involved can it really be?  How about getting an STC for a turbo-diesel engine when they come out?

 

The 262 Trophy Conversion was $69k - $79k, but that included a lot of interior work as well (http://www.mooneymart.com/modifications/100MMA.php)

I don't disagree with your numbers which is why I never traded up...plus, I don't own one of the magic serial numbered 231 airframes....so a 262 was the best I could hope for....if the holder of the 262 conversion is still in business and you had to have a cloned 252, that's the route to go....for me, the cost was simply more than I was willing to pay...

[chrisk]

I wonder why the factory does not offer this path.  It seems like a good way to sell parts.

[Openwheeler3]

Those interested in a 262 conversion may want to contact All American Aircraft. They put a 231 through that process a few months ago to prepare it for sale. I was interested in it but it was already in contract. Sent it to a company in Minnesota I think..

[Openwheeler3]

I guess they never sold it after all...

http://www.controller.com/listingsdetail/aircraft-for-sale/MOONEY-M20K-231/1980-MOONEY-M20K-231/1359619.htm?dlr=1&pcid=17527

[Steve Dawson]

That's a great price for that aircraft.

[231LV]

That is a great price for that plane!

 

...but I'm wondering, in conjunction with the OP, why an MB engine is so important? (The SB gives you 10 more hp but is not available to the 231 airframes) The LB is a vast improvement over the old GB and an auto wastegate can be included...the cowl is not radically different other than cowl flap configuration...I understand the desire for double alternators as the single one is barely enough but otherwise the 231 and 252 are not all that different....I can still get 175 ktas on 10 gph running LOP at 17k ft all day long....doubt a 262 or 252 will get much more on same fuel burn...

[Parker_Woodruff]

The MB has a fully referenced wastegate.  throttle adjustments are almost nonexistent.

 

You pretty much firewall the throttle on takeoff and leave it there till you level off in cruise.