Continental Engine Conversion Service Bulletin

[Q The Engineer]

I spoke with Bob Minnis today regarding TSIO-360 engine model conversions.  Bob is a DER and the original Continental engineer that put the TSIO-360-GB into the J for Mooney creating the K.  He was able to send me this service bulletin.  My understanding is this service bulletin allows you to upgrade engine models with a log book sign off.  See what you think.  I'm thinking on upgrading my TSIO-360-LB to a TSIO-360-SB.  

M75-6R1 Engine Convertion Service Bulletin.pdf

Edited November 16, 2022 by Aaron Q
Added details

[KSMooniac]

While you might be able to convert your engine that simply, that does not authorize you to fly your 231 with the converted engine.  That is the 220 hp variant that Mooney certified for use in the Encore, or 252 models that are fully converted to the Encore configuration.  My understanding is that 231 models are not eligible for the conversion.  You would have to get an STC from the FAA to use the -SB on a 231.

[Q The Engineer]

5 minutes ago, KSMooniac said:

While you might be able to convert your engine that simply, that does not authorize you to fly your 231 with the converted engine.  That is the 220 hp variant that Mooney certified for use in the Encore, or 252 models that are fully converted to the Encore configuration.  My understanding is that 231 models are not eligible for the conversion.  You would have to get an STC from the FAA to use the -SB on a 231.

I'll do some more digging. If I read that service bulletin, it looks like going from an LB to SB is legal.  The base engine is the same.  The major differences are the turbo, aftercooler addition, and tuned runner intake manifold and throttle.  Thanks for the response. 

[Guest]

The SB allows conversion from one engine model to another, but you still need an approval for the engine to be installed in your serial number.  As an example RAM Aircraft converts a GTSIO 520L to a GTSIO 520N for installation in different serial numbers of Cessna421, based on the type certificate.

[kortopates]

49 minutes ago, Aaron Q said:

I'll do some more digging. If I read that service bulletin, it looks like going from an LB to SB is legal.  The base engine is the same.  The major differences are the turbo, aftercooler addition, and tuned runner intake manifold and throttle.  Thanks for the response. 

I am sure there is more to it than the "main differences" you listed.

Regardless though, I used the M75-6R1 to update the data tag on mine when I converted it from a MB-SB - no problem. But Continental provides a parts list, in the form of a kit part # years ago. It gives the detailed list of parts to convert the MB to SB. But to my knowledge they never did that for the LB to MB. The LB has a lot differences from the MB that aren't limited to bolt on accessories - I am not at all sure it possible without a full overhaul. 

But you'll still need approved data or an STC to put the MB or SB in a 231 since the old Mod works STC is no longer available. You could perhaps hire a DER willing to develop you a one  time STC but it will probably be cheaper and faster to sell the 231 and upgrade to a 252 or Encore airframe. 

[Q The Engineer]

13 minutes ago, kortopates said:

I am sure there is more to it than the "main differences" you listed.

Regardless though, I used the M75-6R1 to update the data tag on mine when I converted it from a MB-SB - no problem. But Continental provides a parts list, in the form of a kit part # years ago. It gives the detailed list of parts to convert the MB to SB. But to my knowledge they never did that for the LB to MB. The LB has a lot differences from the MB that aren't limited to bolt on accessories - I am not at all sure it possible without a full overhaul. 

But you'll still need approved data or an STC to put the MB or SB in a 231 since the old Mod works STC is no longer available. You could perhaps hire a DER willing to develop you a one  time STC but it will probably be cheaper and faster to sell the 231 and upgrade to a 252 or Encore airframe. 

Thanks Paul, I pulled the PN's from Continental and have developed the upfit kit part number list.  There are more components change (turbo adapter, fuel lines, etc.), it's a fairly extensive list.  From my comparison the base engines are the same.  I talked with Bob Minnis today on it and confirmed the base engine is the same.  I'll work it some more before I make a decision.  You're likely right on getting a 252 but I'd have a hard time getting rid of the 231.  I've spent the last year going over the 231 from head to toe. 

[Pinecone]

Again, you cannot just install a -SB into a 231.  That is NOT legal.

It doesn't matter if you convert your -LB,  orbuy a new or factory reman -SB.   You need an STC to do so.  ModWorks had one (the 262), but they are gone.

[Q The Engineer]

6 hours ago, Pinecone said:

Again, you cannot just install a -SB into a 231.  That is NOT legal.

It doesn't matter if you convert your -LB,  orbuy a new or factory reman -SB.   You need an STC to do so.  ModWorks had one (the 262), but they are gone.

Thanks for the note and I appreciate the feedback.  My buddy was the original application engineer for Continental on the 231 and 252 and is a DER with the FAA.  He thinks it can be done.  I'm going to dig into it more and see.  Either way, he is able to sign it off.  His point was we're not swinging an engine, we are upfitting an LB to an SB as described in point 1. of the service bulletin.  I have 80% of the parts to complete the conversion so I'm going to dig into it further.  I'll share what I find out. 

[Pinecone]

If you have a friendly DER, that gets it done.

 

[Q The Engineer]

41 minutes ago, Pinecone said:

If you have a friendly DER, that gets it done.

 

Let's hope so!  I'll hit Bob up again. 

[carusoam]

Bob Minnis is a tremendous resource….

He helped guide my decisions when getting a 310hp engine and the TopProp to match… and selecting cylinders….n vs. g.

He is definitely a technical guru…

Make sure you have all the paperwork to match…

It would be a bummer to end up without the proper STC…. Getting around an unavailable STC would be outrageously challenging…

When talking to Bob… be prepared to write really quickly…. The good details come in hard and fast….   

Best regards,

-a-

[tony]

15 hours ago, Aaron Q said:

Let's hope so!  I'll hit Bob up again. 

It does.  Your DER just approves the engineering and your A&P installs the engine to the FAA approved engineering.  Then references the drawing on his 337.  Just ask BOB if he is willing to do that.  

[Will.iam]

Man if he does that i bet there will be quite a few other mooney owners that will want Bob’s number!

[carusoam]

Hmmmmmm….

Tuned intake and throttle swap?

Sounds easy if you have a giant American car…

 

If it were easy….

There would be a lot of Bravo owners looking to do the same…. 

 

Projects of this scale…

Often run into the limitation of finance…

Does it make sense to continue to upgrade this plane… or just buy a plane that is already an Encore…?

 

Is this a forever-plane?

Forever-planes don’t usually run into the usual finance limitation….  
 

Best regards,

-a-

 

[Q The Engineer]

12 minutes ago, carusoam said:

Hmmmmmm….

Tuned intake and throttle swap?

Sounds easy if you have a giant American car…

 

If it were easy….

There would be a lot of Bravo owners looking to do the same…. 

 

Projects of this scale…

Often run into the limitation of finance…

Does it make sense to continue to upgrade this plane… or just buy a plane that is already an Encore…?

 

Is this a forever-plane?

Forever-planes don’t usually run into the usual finance limitation….  
 

Best regards,

-a-

 

I do have a couple of giant American cars with giant v8's.   I guess it depends on who is doing the work.  I build race car engines on the side, have designed and developed diesel engines for 33 years.  It's not that big of deal, approval is though.  I already have 80% of the parts and an A&P/IA buddy so it's doable for me.  

This is a forever plane for me. I've spent the last year going through it, I don't want to do that again! 

[Q The Engineer]

9 hours ago, carusoam said:

Bob Minnis is a tremendous resource….

He helped guide my decisions when getting a 310hp engine and the TopProp to match… and selecting cylinders….n vs. g.

He is definitely a technical guru…

Make sure you have all the paperwork to match…

It would be a bummer to end up without the proper STC…. Getting around an unavailable STC would be outrageously challenging…

When talking to Bob… be prepared to write really quickly…. The good details come in hard and fast….   

Best regards,

-a-

All 100% truth.  Bob is a great resource and a wealth of knowledge.  And I can't write that fast which is why I type it instead. 

[geoffb]

got a line on a 252 cowling?

is your propeller approved on the -SB?

I believe my conversion involved an engine mount swap

the 261/262 conversion was more than a data plate change

[Q The Engineer]

2 hours ago, geoffb said:

got a line on a 252 cowling?

is your propeller approved on the -SB?

I believe my conversion involved an engine mount swap

the 261/262 conversion was more than a data plate change

No cowling yet, it's on the look for list.  I'm not sure on the propellor but I need to check.  I'll check the engine mounts. Thanks!

[carusoam]

What’s the cowl plan?

We have a few Sellers of pre-flown Mooney parts around here…

The Mooney factory may be able to get one made…

Is there a way to modify the existing 231 cowl to the later version?

 

An example of a cowling challenge that the M20J/Missile had… the Missile is an M20J with a six cylinder IO550 bolted on the front…

The Missile needed a cowl that would cover the extra pair of cylinders….

Rocket Engineering wrote an STC that included using a cowl from the M20K…

They also wrote an STC for the Mooney Rocket…. 305hp hiding under the M20K’s cowl…

Fun projects for engine guys….   

Best regards,

-a-

[ToddCC22]

From what I was told the 252/Encore cowl mold was lost in one of the Mooney shutdowns.  It was at an outside vendors location since the Encore cowl was Carbon fiber and that business closed and liquidated during the shutdown. 

[Q The Engineer]

14 hours ago, carusoam said:

What’s the cowl plan?

We have a few Sellers of pre-flown Mooney parts around here…

The Mooney factory may be able to get one made…

Is there a way to modify the existing 231 cowl to the later version?

 

An example of a cowling challenge that the M20J/Missile had… the Missile is an M20J with a six cylinder IO550 bolted on the front…

The Missile needed a cowl that would cover the extra pair of cylinders….

Rocket Engineering wrote an STC that included using a cowl from the M20K…

They also wrote an STC for the Mooney Rocket…. 305hp hiding under the M20K’s cowl…

Fun projects for engine guys….   

Best regards,

-a-

The biggest piece is finding the NACA duct feeding cooling air to the aftercooler.  I believe the duct can be attached to the existing cowling and then cut the appropriate hole in the outer surface.  There are two aftermarket STC offerings that attach the duct to the existing cowling. I'll have to look them up, can't remember now.  Thanks for the feedback A.

[Q The Engineer]

1 hour ago, ToddCC22 said:

From what I was told the 252/Encore cowl mold was lost in one of the Mooney shutdowns.  It was at an outside vendors location since the Encore cowl was Carbon fiber and that business closed and liquidated during the shutdown. 

Sounds like existing used or modification of what I have. Thanks for the info Todd. 

[kortopates]

Sounds like existing used or modification of what I have. Thanks for the info Todd. 

The cowling change between 231 and 252/Encore is much more significant. Remember that two manual cowl flaps changed to 1 larger and very different electric cowl flap with alteration of the engine mount to accommodate the electric motor and cowl flap extension system mechanism. Change is lights, inlets and intake on side.
The only difference between Encore and 252 cowling is $12K in carbon fiber (pricing over 10 years old).
you’ll want to find a salvage 252 fiberglass cowling and engine mount.


Sent from my iPhone using Tapatalk

[Pinecone]

Hmm, if there was a market, someone could build a mold off a good cowling.

[geoffb]

If I was going down this path, I'd put the effort into seeing if I could build a Rocket.  Just not enough juice in LB to MB/SB for the paperwork squeeze.