Time Past TBO Lycoming IO-360

[sdpilot]

I'm currently shopping for a DA40 and was wondering how many of you out there have gone past the TBO of 2000 hours. If you have gone past the recommended TBO I'd be curious to know by how many hours or how many hours did you make it before you needed to do an overhaul. By needed I mean the engine was telling you it needed to be overhaul. I'm not looking for advice on when to overhaul or determine when to overhaul but instead just wondering how much life others have gotten out of their engines before it NEEDED to be taken out for replacement or overhaul.

From what I can tell from the limited information I've been able to find making it to 2400 ETT is easily doable, and can probably go much longer assuming oil samples, compression and everything else remain good during inspections.

Thanks in advance for the information to all those current DA40 owners.

Kyle

 

[John Baker]

As long as an AI will sign it off as airworthy, that is the true life of your engine.

How long would depend on the individual engine and how it has been maintained and treated.

I doubt if knowing how long others have pushed theirs past TBO would be of much use regarding your engine. There are some that don't make it to TBO. That would be another interesting question, how many have had their engine crap out before TBO, and what kind of engine was it?

Either way, the answers have little to do with what you have.

-John

 

[sdpilot]

I understand it has little to do with any one particular engine, and that there are many factors involved, but I am curious to know how many hours others have managed to squeeze out of their engines.

I'm well aware of all the things that go into engine life, but again am really just curious to know how many hours past TBO others have or have gone on their IO-360 engines.

The one I have for example is 2100 with good compression 74,74.73,70 and clean oil samples so I figure it will go another 300 easy.

 

[Dan Thomas]

From what I can tell from the limited information I've been able to find making it to 2400 ETT is easily doable, and can probably go much longer assuming oil samples, compression and everything else remain good during inspections.

There have been operators such as pipeline patrollers or fish spotters that fly their Lycomings to 3500 hours. In such operation the power levels and temperatures and pressures are all pretty constant, there are no short flights, and the airplane flies almost every day. Operators that fly only occasionally and/or fly a lot of shorter flights won't reach higher times like that. Operators who cheap out on maintenance will have shorter engine life. Engines that are abused (rental service comes to mind) will have shorter lives. An engine only needs to be abused once or twice to lose a bunch of TBO.

Lycoming's core refund values drop enormously once the engine is 400 or more hours past TBO.

Dan

 

[Piloto]

My criteria for time to overhaul

1. Idle oil pressure below 25 psi (worn bearings)
2. Compression lower than 60/80 (worn rings)
3. Wet bottom plugs (worn valve guides)
4. Oil consumption higher than 1 qt in 4 hours

José

 

[sdpilot]

Lycoming's core refund values drop enormously once the engine is 400 or more hours past TBO.

I didn't realize that this was true. Do you have any numbers to go with this. If this is really true and the drop is enormous this might be good reason financially not to go too far past TBO assuming other companies suppliers such as western sky ways do the same thing.

I really am more curious what others themselves have seen on their engines past TBO though and not so much advice on when to do an overhaul or what factors contribute to it.

 

[CMTowner]

I didn't realize that this was true. Do you have any numbers to go with this. If this is really true and the drop is enormous this might be good reason financially not to go too far past TBO assuming other companies suppliers such as western sky ways do the same thing.

I really am more curious what others themselves have seen on their engines past TBO though and not so much advice on when to do an overhaul or what factors contribute to it.

I have never had Lycoming reduce a core refund based on hours beyond TBO. The TBO is a recommendation by them, and is not mandated to a part 91 operator. I have turned in cores that have neared 3,000 hours and were still running fine.

The only time I know of Lycoming to set limits on the core and what it is good for is for age. Lycoming will not accept your engine core for exchange on one of their overhauled engines if it is older than 36 years.

 

[sdpilot]

I have never had Lycoming reduce a core refund based on hours beyond TBO. The TBO is a recommendation by them, and is not mandated to a part 91 operator. I have turned in cores that have neared 3,000 hours and were still running fine.
.

That's what I figured. I've never heard of Lycoming or any other engine shop reducing a core refund based on the hours an engine was flown especially seeing the TBO is just a recommendation.

 

[Velocity173]

I got my IO-320 overhauled at 2,200 hrs. I was burning about 1 qt every 4 hrs. One of my cylinders was at 58/80. My mech said it was time. 23 grand later and non AD ECI cylinders are running great. All compressions are 78 or higher.

My IO-360 has 900 hrs and compressions are low to mid 70s. Oil consumption is a bit high at about 1 qt every 5 hrs. Engine was running great until recently. Had to get two new mags. Worked great for a whole 10 hrs and recently started having starting problems. Just got an SB from Champion saying my new mags are bad. Now I gotta send them off to get fixed. Anyway I don't think my IO-360 will make TBO. It just sat too long without being operated. I don't go with the every 12 yr overhaul belief, but mine is at 15 and maybe I'm getting close. Got an oil analysis coming back soon so we'll see what it says.

 

[Lance F]

I have an IO360A3B6D in my Mooney. It was overhauled about 6 years ago by Zephyr Aircraft Engines. It has about 1100 hours since then, and I plan to go past TBO. I get oil analyses every oil change, and everything's great so far.

 

[silver-eagle]

It really matters if you leaseback. Most insurance companies won't let them fly after 10% over TBO. TBO is a best guess anyway. Very conservative. The manufacturers don't want to be on the hook if it explodes on you. My Chevy Tahoe is around 3,500 Original hours (an electronic toy - stock - on board). My Mechanic told me once as long as your compression holds, and you're not too aggressive leaning it out, seeing 3200-3500 hours is quite doable.

 

[Tom-D]

Just IRAN it and keep going, who cares what the numbers are?

 

[sdpilot]

I have an IO360A3B6D in my Mooney. It was overhauled about 6 years ago by Zephyr Aircraft Engines. It has about 1100 hours since then, and I plan to go past TBO. I get oil analyses every oil change, and everything's great so far.

How many hours were on it at the time you did the overhaul 6 years ago?

 

[Cruiser]

My IO360A3B6 went to 6097 hrs on two overhauls both done at 2000 smoh. At 2097 hrs. I decided to quit because the engine was leaking oil from the case, and I noticed more vibration in a full power climb than there was in normal cruise.
I was concerned about loosing the Lycoming $10,000 core exchange if the engine came apart.

 

[Dan Thomas]

That's what I figured. I've never heard of Lycoming or any other engine shop reducing a core refund based on the hours an engine was flown especially seeing the TBO is just a recommendation.

On my invoices from Lycoming, they had a stipulation that the core not have more than TBO plus 400 hours. The core charge was typically $11K for an O-320, and it dropped to half that if over 2400.

Dan

 

[ateamer]

Our O-360 has 2200 hours on it, compression of 79 on all cylinders, uses one quart about every 12-15 hours and the oil analysis from Blackstone Labs is very good. The plane flies once or twice a week, sometimes more, and usually for an hour or so per flight.

 

[LDJones]

O-360 started chewing up a cam lobe at 1,980 hrs. I had replaced two cylinders by then. Know of same engine in Cherokee that made it to 2,400.

 

[Dan Thomas]

O-360 started chewing up a cam lobe at 1,980 hrs. I had replaced two cylinders by then. Know of same engine in Cherokee that made it to 2,400.

Lyc had a few problems with cams maybe 15 or 20 years ago, but the cam issue is more related to oils. The cam is dry when the engine is started after sitting for awhile, and it stays pretty dry because it's above the crankshaft and doesn't get much oil flung at the lobes until the oil warms up some and the RPM comes up. The lifters are the mushroom type that won't let oil run down their length and onto the lobe faces. The O-320-H2AD engine had a real problem with cam failure and you have to use really good oils or additives to prevent trouble.

I know Tom D doesn't like Aeroshell 15W50 but we had really good service out of it for many years, after having much less than satisfactory service from some other oils that didn't have the Lycoming-approved additive that the Aeroshell does.

The real answer is the aftermarket cam some outfit came up with that has oil feed holes on the cam heels. Oil under pressure comes from the cam bearings and oils those lobes instantly after start. I would like to know why Lycoming didn't pay the inventor a lot of money for that instead of coming up with the roller-lifters they use now and which would cost a bunch more to make.

Dan

 

[PPC1052]

Any idea if the Lycoming roller tappets actually work as prescribed?

 

[Lance F]

How many hours were on it at the time you did the overhaul 6 years ago?

About 1700 by the log book. However, it was a field overhaul before I had the plane and I never really trusted it. There were a bunch of irritating oil leaks, so I had it overhauled for piece of mind. The compressions were still all in the 70s.

 

[Dan Thomas]

Any idea if the Lycoming roller tappets actually work as prescribed?

Yes, they do. The last few engines I installed had them and they ran fine.

Dan

 

[LDJones]

Lyc had a few problems with cams maybe 15 or 20 years ago, but the cam issue is more related to oils. The cam is dry when the engine is started after sitting for awhile, and it stays pretty dry because it's above the crankshaft and doesn't get much oil flung at the lobes until the oil warms up some and the RPM comes up. The lifters are the mushroom type that won't let oil run down their length and onto the lobe faces. The O-320-H2AD engine had a real problem with cam failure and you have to use really good oils or additives to prevent trouble.

I know Tom D doesn't like Aeroshell 15W50 but we had really good service out of it for many years, after having much less than satisfactory service from some other oils that didn't have the Lycoming-approved additive that the Aeroshell does.

The real answer is the aftermarket cam some outfit came up with that has oil feed holes on the cam heels. Oil under pressure comes from the cam bearings and oils those lobes instantly after start. I would like to know why Lycoming didn't pay the inventor a lot of money for that instead of coming up with the roller-lifters they use now and which would cost a bunch more to make.

Dan

My engine had the Ney STC for cam lubrication. But the end of a lifter actually fractured and that was what was eating the cam.

 

[N801BH]

On my invoices from Lycoming, they had a stipulation that the core not have more than TBO plus 400 hours. The core charge was typically $11K for an O-320, and it dropped to half that if over 2400.

Dan

Good to see Lycoming has a lot of faith in their product.

 

[ZeroPapaGolf]

Good to see Lycoming has a lot of faith in their product.

Probably just trying to ensure you overhaul whether you need it or not..more profit for them.

Sent via teletype

 

[Tom-D]

Probably just trying to ensure you overhaul whether you need it or not..more profit for them.

Sent via teletype

1 more reason to NOT use the factory to overhaul the engine.

 

[hindsight2020]

O-320 around 2200SMOH on my 28-161 and runs fine. Lowest cylinder was 68 last annual and it was discovered a ring was broken when we pulled the jug months later to patch up an oil leak. Put new rings on it and it's fine. Got lucky, the hole was plated, otherwise no dice on the steel rings. Better lucky than good huh?

I run mine hard (WOT, aggressive lean, 4hr legs x2 every other weekend) and so far so good. I expect to continue flying behind that motor on condition well into 2500SMOH. The cams will probably go and that will be the end of it. That would me my WAG as to what marks the end of it. But who knows. So far so good.

The important thing to note is that the whole business of overhauling engines in my experience comes down to comfort level more than objective science. A lot of people leave money on the table when it comes to engines. It doesn't have to do with any particular lack of information, it's the attitude of the owner/operator and how he/she behaves in regards to that information. TBO is just a manufacturer pushed WAG with higher legal relevance than science relevance IMO, but I have no objection to people who opt to freshen up the working end earlier than necessary. If it gives you peace of mind, knock yourself out.

 

[N801BH]

For reference........

There is a local 172 with a 0-320 in it.. It was topped at about the 2400 mark... Currently it is well north of 4000 hours and running strong.

 

[sdpilot]

1 more reason to NOT use the factory to overhaul the engine.

If I was doing an overhaul I wouldn't use the factory. I think you can get better work done with superior parts from other shops here in the USA such as http://www.coronaengines.com/overhaul.html which looks very reasonable .

If I was abroad in a foreign country I could possibly see the value of going direct to the factory.

 

[Tom-D]

For reference........

There is a local 172 with a 0-320 in it.. It was topped at about the 2400 mark... Currently it is well north of 4000 hours and running strong.

There is a 0-300 that I know of that has been IRANed about every 3000 hours, it is approaching 9000 hours it has been torn down to the crank 4 times.

It's just paper work.

 

[Ted]

Parallel valve O/IO-360 and 320s are pretty much bulletproof. I just talked to someone who ran his IO-360s (it was a twin) to 4300 SMOH before selling his plane - hadn't had to do any work to the engine. The plane was also flying about 800+ hours per year.

Back at Ames Tony used to instruct in a 172 that had 3600 hours on it as I recall prior to someone driving it into a snow bank and prop striking the thing.

2400 hours I would say is pretty easy in general.

Any idea if the Lycoming roller tappets actually work as prescribed?

They do. The intent behind them was to reduce wear, specifically cold-start wear. You don't see them in most turbocharged engines because the cam profiles resulted in a power reduction that hasn't been resolved yet, and I wouldn't expect it to get resolved anytime soon. I think the TIO-540-AK1A (T182 engine) has roller tappets, but the TIO-540-J2BD (Navajo Chieftain) does not.

Aside from the power reduction, they seemed to develop some cam wear issues related to the tappets not spinning like what you'd see in a flat tappet engine, but I don't think that was ever a major issue and may have been fixed.

 

[Dan Thomas]

If I was doing an overhaul I wouldn't use the factory. I think you can get better work done with superior parts from other shops here in the USA such as http://www.coronaengines.com/overhaul.html which looks very reasonable .

If I was abroad in a foreign country I could possibly see the value of going direct to the factory.

I bought factory overhauls because (A) they were cheaper than getting the engine redone at any of the local or regional shops, and (b) because it was a flight training outfit and five or six weeks downtime waiting for an engine to come back was unacceptable. Lyc would ship the engine and would wait up to 90 days for the core to come back. And some of those "rebuilt" engines were brand-spanking-new engines. They were short of cores, I suppose.

I never had any issues with Lycoming's base engines. It was the carbs and magnetos that came with them that were often troublesome. Lyc buys those from other suppliers.

Dan

 

[N801BH]

I bought factory overhauls because (A) they were cheaper than getting the engine redone at any of the local or regional shops, and (b) because it was a flight training outfit and five or six weeks downtime waiting for an engine to come back was unacceptable. Lyc would ship the engine and would wait up to 90 days for the core to come back. And some of those "rebuilt" engines were brand-spanking-new engines. They were short of cores, I suppose.

I never had any issues with Lycoming's base engines. It was the carbs and magnetos that came with them that were often troublesome. Lyc buys those from other suppliers.

Dan

Oh.... How quickly we all forget the "Crankshaft" fiasco Lycoming had a while ago... They were so arrogent they tried to blame the forging company for not doing the "arc remelt" process properly. Till a jury of our peers heard the case and found Lycoming's case without merit and awarded the forging company millions in damages.. Another case of the big guy trying to smear and squash the little guy when the big guy screws up.... I lost all faith in them after that.. IMHO.

 

[Dr. O]

5000+ hours on the left and 6000+ on the right.
Always field overhauled.
Left has a bit over 1000 since the bottom was done and has 300 hours on new Titans.
Right has about 1800 hours on the bottom and 300 hours on new Titans.
IRAN is the method used.

I expect both bottom ends to make it through the first run on the Titans
Engines are junk according to Lycoming (shrug) because they are 40+ years old.

 

[Dan Thomas]

Oh.... How quickly we all forget the "Crankshaft" fiasco Lycoming had a while ago... They were so arrogent they tried to blame the forging company for not doing the "arc remelt" process properly. Till a jury of our peers heard the case and found Lycoming's case without merit and awarded the forging company millions in damages.. Another case of the big guy trying to smear and squash the little guy when the big guy screws up.... I lost all faith in them after that.. IMHO.

There's that, alright. And if you had one of those cranks affected by the ADs, Lycoming would sell you a new crank at a $2000 discount. Considering that a crank can cost $10K or more, this contrasts rather poorly with Ford or GM, who will recall the vehicle and replace whatever is haywire at no cost to the owner. A Lycoming owner had to put up a big wad for a crank, and some shop's labor to put it in.

Something definitely rotten with that.

Dan

 

[Ted]

Oh.... How quickly we all forget the "Crankshaft" fiasco Lycoming had a while ago... They were so arrogent they tried to blame the forging company for not doing the "arc remelt" process properly. Till a jury of our peers heard the case and found Lycoming's case without merit and awarded the forging company millions in damages.. Another case of the big guy trying to smear and squash the little guy when the big guy screws up.... I lost all faith in them after that.. IMHO.

That's not exactly an accurate portrayal of what happened...

 

[N801BH]

That's not exactly an accurate portrayal of what happened...

I HIGHLY respect Ted and I am sure he has alot more info into this situation then he can share... BUT..

Lycoming, Continental, Pratt and all the other aviation motor providers charge a HUGE sum for their products.. The main excuse it the vast amounts of quality control is what drives the price through the roof. It is clear Lycoming sold and shipped motors with a crank defect... people died because of it... They can blame the outside source parts provider till the cows come home.

They need, should and are required by the FAA to have tested EVERY part that goes into the motors. Their failure of a proper QC protocol and the fact defective items were installed on their products because of the lack of proper QC checks does not relieve them of the fact they took the money and sold a defective product.

Just in the last couple of days one poster stated they recieved a rebuilt, yellow tagged motor with defective Champion magnetos.. This happened on a "certified" motor where all componants are supposed to be QC checked... Lycoming can blame pres Bush for the screw up but for all I care, and the FAA for that matter a "Certified engine supplier delivered a NON Airworthy motor and accepted ALOT of someones hard earned money for it...

Bottom line...... If you are gonna sell a airworthy motor, make darn sure it really meets those specs.. IMHO..

Off my soapbox now..

 

[Gary F]

I HIGHLY respect Ted and I am sure he has alot more info into this situation then he can share... BUT..

Lycoming, Continental, Pratt and all the other aviation motor providers charge a HUGE sum for their products.. The main excuse it the vast amounts of quality control is what drives the price through the roof. It is clear Lycoming sold and shipped motors with a crank defect... people died because of it... They can blame the outside source parts provider till the cows come home.

They need, should and are required by the FAA to have tested EVERY part that goes into the motors. Their failure of a proper QC protocol and the fact defective items were installed on their products because of the lack of proper QC checks does not relieve them of the fact they took the money and sold a defective product.

Just in the last couple of days one poster stated they recieved a rebuilt, yellow tagged motor with defective Champion magnetos.. This happened on a "certified" motor where all componants are supposed to be QC checked... Lycoming can blame pres Bush for the screw up but for all I care, and the FAA for that matter a "Certified engine supplier delivered a NON Airworthy motor and accepted ALOT of someones hard earned money for it...

Bottom line...... If you are gonna sell a airworthy motor, make darn sure it really meets those specs.. IMHO..

Off my soapbox now..

Is there a non-destructive test that could have detected the flaw in the crank?

 

[Ted]

Is there a non-destructive test that could have detected the flaw in the crank?

If there is, I'm not aware of it. The flaws were found by cutting the cranks open and finding the defects internally. I'm not sure what you would do to find those otherwise. Doesn't mean a process doesn't exist, just that I don't know what it would be.

The real reason for the high cost of piston aircraft engines is insurance due to lawsuits. That makes up about 50% of the cost of the parts. For turbines, you have a combination of lawsuits and advanced technology in making thrts. Pistons get a bit of the low production number issue factoring into price, but not as much since the technology is pretty basic.

Not saying Lycoming (or any OEM) are angels with no faults. Magnetos are one or the worst areas, with a ridiculous number of bad ones sent out. That said, aviation companies really hate getting sued. The big guys pretty much always lose (grieving widows sway juries more than facts, and the common feeling is the big company can afford the lawsuit), and it costs a lot of money. They have no incentive to send out junk for this reason. That said, junk will slip through the cracks for various reasons.

The real question: what level of reliability are we willing to pay for? As it is, we all complain about high costs. Are we willing to pay more for increased reliability? How much more for how much perceived reliability? What level of confidence do we need when a new supplier is picked for a part, which happens regularly? Remember, this is for a commodity that sells on the order of 1,000 engines per year.

 

[pilotx86]

My Warrior has the O-320-D3G and has 2900 SMOH. Burns 1 quart every 7-10 hours and compression's on cylinders 1-4 are 79, 79, 70, 78 with no unusual wear in the oil analysis every 50 hours. It had been used as a trainer at a flight school (on leaseback - huge mistake) and I currently fly at least once a week to operating temperature for at least 45 minutes at normal cruise.

Just like a previous thread said, keep flying until the IA says no more. That's all relative though depending on your flying habits; Having it sit around is pretty bad for any type of machinery.

 

[Skip Miller]

My criteria for time to overhaul

1. Idle oil pressure below 25 psi (worn bearings)
2. Compression lower than 60/80 (worn rings)
3. Wet bottom plugs (worn valve guides)
4. Oil consumption higher than 1 qt in 4 hours

José

Just curious... you overhaul if the engine hits one of those criteria, all four, or ???

-Skip