Engine TBO and Engine Times

[Seth]

During the post about ground backfiring, I realized that I know of a sterotype of Mooney's out there to not make it to TBO.  Let's see if we can debunk this fact.

1.  What kind of Mooney do you have

2   What is your current engine time - not any problems, issues, top overhauls, etc . . .

3.  If you have replaced/overhauled an engine, did you make it to TBO?  What was the time on the engine?

Let's keep this to Mooney Aircraft for now, but if you feel that you have to share another aircraft, feel free.

Also, please make sure to list if your engine is not a 2000 TBO (it will be assumed 2000).

 

I'll start

1.  1967 M20F

2.  320 hours - ground backfiring/popping, clogged fuel injector - easily fixed.

3.  The former owner replaced the engine due to a cracked casing - I do not have the time as its in the logs which are at the shop.

[Parker_Woodruff]

1.  1990 Mooney M20J-AT

2   Approximately 1400 SMOH, 350 since top with cermanil cylinders several years ago.  Bought the plane in February.  All compressions are mid-high 70s.

3.  My airplane is on its fourth engine, IIRC.  It has generally gotten about 1900 hours before overhaul, but that was all by Embry Riddle

[wmrunyon]

1. M20M 1991

2. Current engine time 950 hours, Lyc reman; only engine problem has been with the exahaust system, expensive to repair or replace.

3. The 1st engine made it to 1850 hrs.

[eaglebkh]

1. 1964 M20E

2. Current engine (engine #2) is at 900 hrs with a new #4 cylinder at 600 hrs

3. 1st engine made it to 500 hrs (replaced in 1970 with factory reman)

So, if you can do the math - my engine is nearly 40 years old with 900 hrs.  I know, that's only 23 hours per year on average, but it is running really smoothly with high compressions and slightly higher-than-normal oil burn.  This winter I am looking at OH, though, because my mechanic isn't going to sign off on the annual again with a 40-year-old engine and I agree.

[KJATCt]

1. 1965 M20E

2. 1918 hrs

Original jugs, compression all in the mid 70s with +/- 3 spread. I fully intend to go past 2000 hrs.

[Jeev]

1978 M20J

1500 SFOH in 1993

Lowest comp found on annual insp last month was 76/80, runs strong with average oil burn, plan on running it as long as she is healthy.

[Cruiser]

1984 M20J

6097.0 hours on the original engine.

replaced in 2008.  85 hrs. on FREM

 

[jrjaks]

Present Mooney:

1982 M20J

500 SMOH

Crankshaft AD-replaced at 300 SMOH, (new pistons, rings, etc.)

Premature Cam wear - replaced by Lycoming 450 SMOH, (new pistons, rings, roller tappets). Running great.

Previous Mooney:

1963 M20C

Sold with 2800 SMOH, running great when sold.

[N9937c]

m20k 1981 1954 sreman never had a cylinder off just checked comp. low 73/80 high 78/80. 1 qt in~ 20 hours

Is intercooled and spoiler equipted

larry

[jlunseth]

If you are getting compressions in the 70's on the Continental engine you might want to have a Mooney shop check the compressions.  I don't know the technical part.  I think most shops just catch the momentary highest pressure on each cylinder, while the correct way is to move the prop around and see what pressure the cylinder will actually hold.  Measuring the pressures correctly will usually get you into the 50 and 60's on the Continental. 

[N207LS]

1. 1968 M20G (Lycoming O-360)

2. 650 SMOH (2004) done at Devine Aircraft Engine, TX, Former owner did MOH and replaced all four cylinders with new Millennium Cylinders.  www.superiorairparts.com/millenniumCylinders.asp.   He also added the Powerflow Exhaust at that time.  www.PowerflowSystems.com.  And the K&N air filter mod.  This was the second overhaul on this engine (3600 AF TT), the first was a field overhaul done in 1986 at ~ 1700 hours.

3. Compression from last annual was 74-75-75-78.  Currently burns about 1 quart every 8 hours of flight time.  No engine issues since I puchased the plane in 2005 with 40 SMOH.  Have only had to replace the starter since and went to the new Sky Tech. 

Aaron

[Seth]

1984 M20J

6097.0 hours on the original engine.

replaced in 2008.  85 hrs. on FREM

 ----------

Did you really have 6000 hours on the original engine?  How many overhauls?  How many problems?

[FlyDave]

Quote: Seth

1984 M20J

6097.0 hours on the original engine.

replaced in 2008.  85 hrs. on FREM

 ----------

Did you really have 6000 hours on the original engine?  How many overhauls?  How many problems?

[Guest Anonymous]

Quote: N207LS

1. 1968 M20G (Lycoming O-360)

2. 650 SMOH (2004) done at Devine Aircraft Engine, TX, Former owner did MOH and replaced all four cylinders with new Millennium Cylinders.  www.superiorairparts.com/millenniumCylinders.asp.   He also added the Powerflow Exhaust at that time.  www.PowerflowSystems.com.  And the K&N air filter mod.  This was the second overhaul on this engine (3600 AF TT), the first was a field overhaul done in 1986 at ~ 1700 hours.

3. Compression from last annual was 74-75-75-78.  Currently burns about 1 quart every 8 hours of flight time.  No engine issues since I puchased the plane in 2005 with 40 SMOH.  Have only had to replace the starter since and went to the new Sky Tech. 

Aaron

[Cruiser]

Quote: Seth

1984 M20J

6097.0 hours on the original engine.

replaced in 2008.  85 hrs. on FREM

 ----------

Did you really have 6000 hours on the original engine?  How many overhauls?  How many problems?

[N207LS]

RFB,

I keep my oil level at 6-7 qts.  Eight means one on the belly and seven for the engine,so I add one every time it gets to 6.  Minimizes fresh oil on belly.  I put 7 in at the oil change as well.  This seems to work for me.  I have considered the M20, but haven't pulled the trigger yet.  Let me know if you do it and your results.

Aaron

[Parker_Woodruff]

Quote: JimR

1) 1978 M20J - 10,090 hours TTAF 

2) 2855 hours on FNEW (Engine #1)

    2894 hours on FRMN (Engine #2)

    2816 hours on FRMN (Engine #3)

    1525 hours currently on FRMN (Engine #4)

3)  My plane was used by a radio station in the San Francisco Bay area for the first decade or so of it's life, which is where it racked up almost all of it's time.  Since all of the engines were factory remans, I don't have logs for them, but Tom Rouch of Top Gun Avation maintained it during those years, and he has told me that all of the engines made it beyond TBO without serious problems.  The current engine has also had no engine problems during my tenure and according to the logs.     

[MooneyPilot231]

Glad to see someone post about the Continental compression numbers. I bought my plane with less than 200 hrs on a FRME and the compressions were right at 70. My A&P was the one that told me that was perfectly normal for a Continental, especially a turbo charged Continental. (require much bigger ring gaps) It is almost impossible to get my engine within 100 deg. of where it actually runs during a ground run up with the top cowl off so there is no way to get an accurate test reading really.

Again, having owned a very high end race engine shop and having built engines making over 1900 h.p., I would like to point out that what aviation calls a compression test is in fact a leak down test. In truth, it almost useless as a diagnostic tool to determine the condition of an engine. An engine with good numbers can burn oil like a bandit and another with compression readings in the mid 60's could be perfectly healthy. I know most people refuse to believe this, but it is a fact!

My plane's first engine, the GB model, made 1600 with no top overhaul. Current engine has 400 hrs....

[skyking]

First engine made it to 1850 hours but it was not looked after very well and the aircraft sat for a long time without being used.

Current engine only has 200 hours and the prop, hub, spinner etc is only a month old.

 

russ

[mooniac58]

1987 M20J - 1890 SMOH 550 STOH

Compressions range 74-77 on all cylinders, I do oil analysis at every oil change which is 25-35 hours and it is always good.

I don't feel any need to overhaul at this time although the IO-390 does tempt one a little

[lahso]

1.  1966 M20C.

2   175 hrs.

3. Did not make it to TBO. 1800 hrs were on the engine at the time I decided to do a major overhaul. Previous owners did not fly very much (it didn't sit for long periods, but they put only a few hours a month on it).

 

[Ned Gravel]

Mine made it to 1951 hours before leaking oil at one of the lower bolts on #2 caused us to check for binding on the shaft.  Turns out there was a 7" crack in the case from that bolt going aft and down.  Major overhaul time. 

I do not believe it was looked after very well before I bought it at 1640 hours.  Now it is 25-30 hours for an oil change and I have a JPI on board to keep an eye on things.  Manage the temps and use it a lot.  That is what my AME (A&P for y'all) tells me.

[HopePilot]

One of the planes I'm looking at was rebuilt in 1990 and has about 700 hours on it.  How long past Lycoming's 12 year TBO recommendation do you guys feel safe with?

[Cruiser]

check the NTSB database. Search for accidents that were caused by engines too old for continued flight into normal conditions. (kidding of course)

[JBrown]

2000 M20S Eagle, 310hp

Currently 2189.7, prop strike and tear down in 2004 (previous owners...).  Two new cylinders (one ECI, one Conti) so far.

 

Currently keeping it on a tight leash with the EDM, and the mechanic here at SouthWest Texas Aviation says we should get another 200-300 hours no problem.  I am having the sagging engine mounts replaced next week though.