M20K 231 TSIO-360-GB vs. LB

[ifrflyer]

All,

 

I am currently ready to cross over from the renters world to ownership.  I was going to buy a Cessna TR182RG until I came across a beautiful Mooney on Controller.  I don't know much about Mooney's, except they are efficient and fast.  

 

The Mooney that I am looking at (http://www.controller.com/listingsdetail/aircraft-for-sale/MOONEY-M20K-231/1980-MOONEY-M20K-231/1300287.htm) has a TSIO-360-GB engine.  

 

My questions are as follows:

 

1) Can this GB engine be converted to an LB engine?  Or a MB/SB engine for that matter?

 

2) If it can, could I keep the intercooler, Merlyn waste gate, and GAMI injectors?  

 

3) What do overhauls for these engine types typically cost? 

 

4) Can you fit skis (170cm) in the M20K?  

 

5) The owner of this Mooney guarantees 170 knots above 15,000 with a fuel burn of 9.5 to 9.8 gph.  Does this sound realistic to everyone? 

 

6) How does the deal itself look to everyone? 

 

Again, I am new to Mooney's.  I was going to go with Cessna, but I am starting to shy away due to the operating costs.  Thank you in advantage for your expertise and I look forward to hearing back!

 

 

[Dave Marten]

I haven't had any problems with my GB. Intercooler and autowastegate make the GB a sweet engine.

1. Yes GB will get upgraded to LB at OH.

2. Yes keep your mods- seemless transfer

3. Comparable to other 6 cylinders. I'd guess 30k plus although I haven't gotten there yet

4. Should be able to, over rear seat

5. No. I don't trust blanket statements like that. About 2 gph low for 170 at 15k. If you're going to guarantee performance at least spell it correctly!

6. Great avionics, good numbers, fair price. There are less expensive 231s out there but you'll give up a little 'glass'. Hint- check the listings on this site

[ifrflyer]

Thank you for the quick response Dave.  I'm new to this site, so I'll check the postings on here as well. 

[carusoam]

Dave,

I thought you were going to ask why his skis were so short?

Best regards,

-a-

[podair]

Dave,

I thought you were going to ask why his skis were so short?

Best regards,

-a-

Indeed  . My 178cm ones fit in my M20F (same cabin) easily, although across the rear seats obviously. They can stick out into the hat rack if needed. I think someone here once posted a pic of a ski tube in the rear fuselage, through the access panel, looked like a fabric sack that was suspended. 

 

Sorry can't answer any other questions, I'd love a 231 too! The one you posted looks great, especially the panel.

[FAST FLIGHT OPTIONS LLC]

I routinely see 175ktas @ 17k on 9.5 gph LoP GB engine. No intercooler No Merlin waste gate. No glass panel. No wishful thinking

[231Pilot]

Ski tubes are available.  My 1985 had a ski tube installed when I bought it.  Of course, I am not a ski enthusiast, but the tube remains in place. 

[mikesalman]

That was me with the ski tube in my 68F. I'm thinking about having it removed, I don't ski and I hate cold weather. It will be up for grabs on Mooneyspace when I do. 

[Bob]

Looks like a pretty nice plane!  A lot of good stuff and very strong points.  Aspen, fresh tanks, new biscuits, traffic, intercooler, etc.  Not sure of current market, but looks like this is one that too much stuff was added, that the owner will never get money back for.  I heard engines are about 45k??

 

One thing that catches my attention, why does he have portable O2?  Looks like many things were done right, but why didn't he fix the factory O2.  Did this one not come with O2?  Was the $3500 regulator and $2000 new bottle due?   Not a big deal, but would ask to find out the story.

 

I would check into this one if I was shopping.

[ifrflyer]

That is a good question about the O2.  I'm not sure if the aircraft has factory O2.  I'll ask.

 

I am in amazement this thing can do 170 TAS on <10gph!  

 

I did read in the logs the plane had a prop strike in 1997.  Block was repaired and crank was ok.  An overhaul was performed and it has had 900+ hours on it since.  

 

I'll call around today for engine cost and report back.  

[chrisk]

From a quick glance, it looks like a nice plane to me and has a lot going for it.  But, it is approaching the price of some M20K 252's.  An example is http://www.trade-a-plane.com/detail/1721975.html (I don't know this plane).   And in general, a 252 is going to perform better.

 

A few things stand out.

• I'm guessing this does not have built in O2.   It is convenient, but expensive to maintain, takes useful load, has to be filled at the airport.
• It doesn't have speed breaks, which are a nice to have item.
• The panel looks nice, but the switches don't look like the ones that came with the plane.  I'd make sure the paperwork is good.  --I'm not an expert in this area, so it may not need anything special.

If I were in the market, I'd push on the price and make sure a good pre-purchase inspection was done by a knowledgeable shop.  I've heard good things about Henry Weber Aircraft in PA.

[ifrflyer]

Wow… The 252 is quite the performer, but the market is definitely scarce.  Are fuel burns similar as well?  

[KSMooniac]

That plane does seem to have a lot going for it at that price.  I especially like the pic of the records!  Everything is likely squared-away with this plane if I had to guess.    Cosmetics are advertised as "fair" and perhaps that is a bit conservative, but maybe they don't look as nice in person.  I'd rather get a solid plane with ratty cosmetics and then fix those to my specs on my own schedule/budget.  Having a tank reseal is very, very nice too.

 

I know the '79 (first year) K's didn't have factory oxygen, and it is possible that this one didn't have it either as it is a relatively low serial number, perhaps built late in '79 and sold as an '80 before the option was available or standard.  

 

Definitely check out Dave M's K advertised here too.

[KSMooniac]

Wow… The 252 is quite the performer, but the market is definitely scarce.  Are fuel burns similar as well?  

Yes, they are similar.  The 252's firewall-forward installation is essentially the next generation of the 231 and much more optimized.  Some of them got fat, though, and lost payload.  It is possible though to convert a 252 to the "Encore" configuration which was the last of the M20K line and get a 230 lb gross weight increase, which of course helps immensely with payload.  You cannot do this to a 231.

 

I'll also add that the 252's have more of the airframe upgrades that become common in the mid-80s and later, such as the 1-piece belly panel, removable rear bucket seats, etc. that may or may not be on any particular 231 you might find on the market.

[Z W]

1) Conversion to LB is required at overhaul.  MB STC is out there, but nobody seems to have done it in a long time.  Somebody posted a quote for it a few months back, and I think it was $70k or so, including the new engine.  SB was done recently on a 252 by a forum member.  Not sure if you could get it done on a 231, but possibly. 

 

3) Overhauls will be 45-55k, if you include the turbo and associated parts.

 

4) 170cm skis will fit just fine, length wise, but will hang over the back seat, and in a crash, are probably going right through the back of your head.  You might want to find a model with the split rear seats.  Those come out very easy so your skis can lay down on the floor.  They're also wonderful for loading purposes.  I've had a bench rear seat and now have split folding seats, and would express a very strong preference for the rear folders.

 

5) 170 kts over 15k on 10 GPH is about right.  You will be on oxygen staying at those altitudes.  You will only be up there on about 1/3 of your flights, when there's a tailwind.  Otherwise, you will be at 10-12k doing 170 kts on 11ish GPH, or slower on less.  Still no slouch. 

 

6) This is one of the nicest looking 231's I've seen listed.  It's also one of the most expensive.  It's got a lot going for it, but it's competing with the 252's at that price.  The 252's come with the MB engine, a second alternator, split rear seats, factory oxygen, and usually speed brakes / hot prop / extended range tanks.

 

Certainly worth a hard look, just be aware of the options some other planes might offer.  You might also look at Rocket conversions.  Less efficient, but a lot faster, and you're close to Rocket price range here too.

[Parker_Woodruff]

Wow… The 252 is quite the performer, but the market is definitely scarce. Are fuel burns similar as well?

The 252 market is far from scarce (from an economics perspective, true there may only be about 15-20 for sale at any given time throughout the whole country). Those planes aren't moving. I had one of the best performing 252s out there (converted to an Encore) with brand new paint and a decent IFR package. Took me about 4 months to move it, despite it being priced very competitively.

[ifrflyer]

Can you get FIKI TKS for the 231 or only non-certified TKS?

 

*EDIT: I think I figured this out on my own.  Dual alternators are required on the FIKI system and the 231 only has 1.  

[gjkirsch]

Can you get FIKI TKS for the 231 or only non-certified TKS?

 

*EDIT: I think I figured this out on my own.  Dual alternators are required on the FIKI system and the 231 only has 1.  

If you want TKS on a plane, try and buy one with it already installed.  There are a selection of Mooneys out there available with TKS with the price delta between a TKS equipped plane and one without less than half the cost of the TKS installation cost.  

[ifrflyer]

I would love to find an aircraft with TKS already installed.  My missions involve 3 or 4 CA to Upstate NY trips.  Icing in upstate NY is horrible. The rest of the missions are flying around the southwestern states.  I guess FIKI isn't a must, but would be very nice.  

 

Looking for a balance between utility, speed, and efficiency.  

[RJBrown]

I owned a 1980 231 it was Serial # 0232. It came with factory O2. This one should have had it. Only the 1979 planes were without O2. I always carried a back up O2 bottle. None of his pictures show where the O2 fittings would be. E bottles pictured would be small for anything but flying alone. 1 bottle would not last a full tank of gas for 4 people. The Sky-Ox ads say otherwise but dont believe them. It is just like a 231 that wont do 200 knots as advertised.

[ifrflyer]

Is it possible to make a 231 into a 252? 

[FlyDave]

From a quick glance, it looks like a nice plane to me and has a lot going for it.  But, it is approaching the price of some M20K 252's.  An example is http://www.trade-a-plane.com/detail/1721975.html (I don't know this plane).   And in general, a 252 is going to perform better.

 

I looked at this plane. Paint is very nice, interior is OK, nice panel (this is the plane that sold me on the 696 as an MFD) and good maintenance records. It's at Stockton, CA (KSCK) which is where Top Gun is and LASAR is ~100 nm away so getting a prebuy done at a good shop is a no-brainer.

[Z W]

Is it possible to make a 231 into a 252? 

 

More or less.  That is what is called the 262 conversion (I fly one).  It was done by a company called ModWorks.  The STC's are still around, although the company isn't.  They took a 231 and put a MB engine, speed brakes, hot prop, and extended range tanks on it.  Some, like mine, even modded the windows to be rounded on the corners like the 252's instead of square like the 231's.

 

The only difference between a full 262 conversion and a 252 is the 262 has a 14-volt electrical system, instead of the 24-volt on a 252.  It uses different voltage regulators, but I think has the same alternators.

 

The conversion is no longer economically feasible.  Right now it's cheaper just to buy a 252, rather than buy a 231 and convert it.  But you can sometimes find a 262 for sale, and usually significantly cheaper than a 252 because it's a "modded" airframe.  They are a great value.

[ifrflyer]

I looked at this plane. Paint is very nice, interior is OK, nice panel (this is the plane that sold me on the 696 as an MFD) and good maintenance records. It's at Stockton, CA (KSCK) which is where Top Gun is and LASAR is ~100 nm away so getting a prebuy done at a good shop is a no-brainer.

This plane is great, but the compressions are getting low (one cylinder in the 50's, two in the 60's.  So I should probably factor that in right away.  

 

Why didn't you pull the trigger on this one? 

[KSMooniac]

50's and 60's on Continental engines aren't too far out of the ordinary.  A borescope inspection of the valves would be in order, but those aren't necessarily bad numbers.