Engine Overhaul Price 2025

[exM20K]

My primary considerations in choosing to top a 1700 hour engine vs O/H:

1. Treat the symptom.  High oil consumption and oil that would get dirty on the first run-up (it seemed.) The CMI crankcase test scored very badly, cross-hatch was very worn, so the cylinders needed to be replaced.  The rest of the engine is fine, with 0 corrosion and no metal ever in the filter, so why throw out a working reliable engine?
2. Recent Major Components repaired or replaced.  2 Turbo’s, mags, harnesses, fuel pump all replaced within the last 100 hours.
3. Invasive MX / Infant Mortality.  Less stuff is disturbed, so less opportunity for things to be done wrong/poorly.
4. CAPEX /Time value of money.  Just to make the math easy, let’s assume optimistically that the O/H costs $100,000 more than the top. At an 8% cost of funds, that o/h costs $8000 per year more.  The hours on the “new” cost another $10,000 in blue book @150 hours per year.
5. Downtime. I need the plane to run my business.  Germ tube is massively inconvenient to the point of pointlessness.  Top, even though it didn’t go great, is significantly less downtime.

Unless someone beats me with a money stick, I plan on keeping this plane for a while. So at the rate I’m flying, if I can get another 5 years/750 hours out of the engine, then I’m nearly $100,000 ahead on a cash flow basis.  There are, of course, no guarantees, save for the skinny warranty that the overhauler offers.

As @aviatoreb is discovering, these engines are astonishingly expensive (Victor super-dooper overhaul quote $130,00++), so anything that can economically extend the life of the engine in place seems prudent to me.

The financial figuring, done with an appropriately dull pencil, is just rationalization. For me, it was higher confidence in the engine and less downtime that drove the decision. YMMV.

-dan

[A64Pilot]

100K MORE to overhaul than to top? You must be flying a Twin and wanting to do both?

Nothing says you have to replace all accessories, hoses etc. When I overhauled my Maule I didn’t, and didn’t have any real issues from not doing so. 

If I were 300 from TBO, I’d either nurse the thing or more likely IRAN the cylinders and start saving for an Overhaul.

If they are as worn as you say you can most likely have them honed to next size, new pistons and rings, have valves at least inspected and refaced and get at least another 500 hours out of them.

The fear of removing cylinders is way overstated, really all that’s needed as a min is remove a cyl, place spacer or I have seen a few fender washers and torque them down, go to next cylinder. The  torque plates for Lyc are cheap, surely the same is true for a Conti. Too cheap to justify fender washers.

One of I’m sure many sources for Lyc torque plates

https://flyboyaccessories.com/products/cylinder-torque-plate-for-lycoming-engines

[exM20K]

@A64Pilot I think we are on the same page here, except as to the cost of the big bore turbo o/h.  It is shocking, but they are well in excess of $100k now, both CMI and, I believe, Lyc.

I did top o/h  only partially because of new components, but in my case, the jugs had been punched 0.001 over once before, so at 1700 hours, there was nothing left but to mulch them.

Agree 100% on the Mike Busch-fueled anxiety over cylinder R&R.  Shop had torque plates, and this sort of work happens dozens of times across the county daily w/o planes lawn-darting all over the place.

-dan

[A64Pilot]

52 minutes ago, exM20K said:

@A64Pilot I think we are on the same page here, except as to the cost of the big bore turbo o/h.  It is shocking, but they are well in excess of $100k now, both CMI and, I believe, Lyc.

I did top o/h  only partially because of new components, but in my case, the jugs had been punched 0.001 over once before, so at 1700 hours, there was nothing left but to mulch them.

Agree 100% on the Mike Busch-fueled anxiety over cylinder R&R.  Shop had torque plates, and this sort of work happens dozens of times across the county daily w/o planes lawn-darting all over the place.

-dan

I had no idea they cost that much to overhaul. I’ve been an A&P for a long time, I remember thinking about 1990 or so while I was still in the Army that my cost in parts and services that I would have to farm out to overhaul an engine was less than $2K a cylinder, meaning 8K for a four cylinder engine, new cylinder kits complete with everything were I think about $500.

I think I spent about $10K to overhaul my IO-540 in roughly 2007 or so and I cut no corners, actually spent more than I should buying new Millenium cylinders rather than having mine overhauled, that was a mistake. In truth I don’t keep track of costs as if I did I’m sure I couldn’t logically justify owning an aircraft. I prop struck it at about 1800 hours or so and I decided that if it was coming apart for inspection that I was going to overhaul it.

It was so cheap to overhaul largely because it was low time and I didn’t have to replace anything except bearings etc. I did send the rods off to be rebuilt, crank to be inspected, it still met new tolerances and only needed polishing, cam and lifters to be ground and nitrided, I had the counterweight bushings replaced. Cases went to Divco, they found a crack to weld, but you could not find the repair, I looked. 

Its a lot like your brakes on your car, if you change pads when they are about half gone and flush the fluid, it’s easy, takes only a few min per wheel and is cheap, but if you wait until it’s metal to metal, well then your buying new disks and pads and as it’s been years since the calipers were flushed maybe calipers too.

I’m a strong proponent of preventative maintenance.

If you run your engine until it’s making metal, best I think to buy a factory overhaul and turn in yours as a core, because once it’s making metal, it’s very likely your crankshaft, cam, oil pump etc are gone, your oil lines, cooler need replacing, and your prop and governor need overhauling as well, anything that oil touches is contaminated 

 

[Pinecone]

On 4/6/2025 at 8:20 AM, Danb said:

Probably nothing Erik, I have friends with boats

Was overhearing a conversation at the airport between two boat owners.

One was saying that the last bill he got for work on his boat was $135,000.  WOW.  You can buy a nice Mooney for that

[toto]

Air Power lists a brand new TSIO-550-G at $117k with a core exchange. 

Is the crazy overhaul price just because these things are unobtanium?

https://www.airpowerinc.com/tsi0550g5bn

[aviatoreb]

On 4/6/2025 at 10:12 AM, exM20K said:

My primary considerations in choosing to top a 1700 hour engine vs O/H:

1. Treat the symptom.  High oil consumption and oil that would get dirty on the first run-up (it seemed.) The CMI crankcase test scored very badly, cross-hatch was very worn, so the cylinders needed to be replaced.  The rest of the engine is fine, with 0 corrosion and no metal ever in the filter, so why throw out a working reliable engine?
2. Recent Major Components repaired or replaced.  2 Turbo’s, mags, harnesses, fuel pump all replaced within the last 100 hours.
3. Invasive MX / Infant Mortality.  Less stuff is disturbed, so less opportunity for things to be done wrong/poorly.
4. CAPEX /Time value of money.  Just to make the math easy, let’s assume optimistically that the O/H costs $100,000 more than the top. At an 8% cost of funds, that o/h costs $8000 per year more.  The hours on the “new” cost another $10,000 in blue book @150 hours per year.
5. Downtime. I need the plane to run my business.  Germ tube is massively inconvenient to the point of pointlessness.  Top, even though it didn’t go great, is significantly less downtime.

Unless someone beats me with a money stick, I plan on keeping this plane for a while. So at the rate I’m flying, if I can get another 5 years/750 hours out of the engine, then I’m nearly $100,000 ahead on a cash flow basis.  There are, of course, no guarantees, save for the skinny warranty that the overhauler offers.

As @aviatoreb is discovering, these engines are astonishingly expensive (Victor super-dooper overhaul quote $130,00++), so anything that can economically extend the life of the engine in place seems prudent to me.

The financial figuring, done with an appropriately dull pencil, is just rationalization. For me, it was higher confidence in the engine and less downtime that drove the decision. YMMV.

-dan

I’m glad I did the major overhaul - my crank turned out to be in sufficiently poor shape they replaced it and my engine case needed some work so a top would not be enough.

[76Srat]

All good stuff here, guys.  I've said it before and I'll keep saying it:  Is this reality?  Yes, it is the new reality.  Therefore, are we still going to be staring at the top of our boots in the next 20 year timeframe and lamenting the extinction of our legacy piston fleet?  And I'm including all legacy pistons in that assumption, not just our beloved Mooneys.  Unless there is a drastic and universal change in equipment being available to the legacy piston fleet, it will no longer exist as we know and love it.  Period.  

I argue that we should stop expecting the factory/field OH market to somehow come back to earth and show us a welcome "correction" as to what all of that costs.  What has never been controversial or refutable is how one owner chooses to undertake such a project.  

As we've all discussed above in this very topic, each owner/operator is different than the next.  Some might choose to overhaul/replace literally everything from the firewall-forward.  Others choose to do such on an as-needed or for-cause basis.  Its Ford vs Chevy at that point and that's been the prerogative since airplanes went to maintenance for the very first time ever.  That will never change.  What does need to change, and I argue what must change, is what we expect to happen if we stay the course and simple expect the certified piston engine marketplace to somehow all of a sudden be transformed into something we think we can all live with.  Bluntly, it won't.  Without new technology on the power plant side for the certified legacy piston fleet, this is a race to the bottom with only one possible result:  extinction.  There is no help from the newly-certified crowd (read:  Cirrus et al), nor is there any help from the regulatory agencies themselves (FAA/EASA et al).

Instead of lamenting and wishing for short-term solutions (which are anything but "short-term" in their pursuit) such as UL100 or other band-aid so-called solutions for existing piston power plants, we should be lobbying for and arguing in favor of replacement power plants themselves (small turbines/diesel-derivatives, etc.).  This may sound like crazy talk and will be crazy-expensive, but it truly is the only way out of this mire and mess, if we truly want to save our legacy piston fleets.  

Where would the piston fleet be if there were no investment or tech which replaced our beloved steamguages a few decades ago?  Look at what Dynon and Garmin have done for that?  Could and should there be the same type of focus for the powerplant side?  I argue not only should there be; there must be.  Otherwise, our legacy pistons will be seen by our grandchildren in the occassional static display museums, which will be few and far between.

I'll pop some popcorn and now watch the wailing and gnashing of teeth over this thought . . .

 

[hammdo]

Something Mike Busch noted would be interesting- E-CB  experimental  commercial build classification - for the aging fleet. Allowing owners to do what experimentals do….

https://www.aopa.org/news-and-media/all-news/2025/march/pilot/savvy-maintenance-worth-the-squeeze

-Don

[76Srat]

17 minutes ago, hammdo said:

Something Mike Busch noted would be interesting- E-CB  experimental  commercial build classification - for the aging fleet. Allowing owners to do what experimentals do….

https://www.aopa.org/news-and-media/all-news/2025/march/pilot/savvy-maintenance-worth-the-squeeze

-Don

Great article, Don.  I echo the expectation that it'll take regulatory agency help in softening a few of the key sticking points on certification processes, etc., especially those related to the sheer expense directly related to getting new powerplants to market that can be drop-in replacements for legacy piston-powered airplanes.  The reason why those are so expensive is because of the obvious:  the OEMs return on investment.  

As to why the factory OH route is so expensive is a mystery to me because legacy certified powerplants were monetised decades ago by the OEMs.  I think its merely a marketplace commodity factor and nothing else, which will not be sustained long-term.  

It'll take agency and private industry partnerships to make anything sustainable happen (much like we now see taking shape nicely on the avionics side).  Until then, we should be planning on spaces in the mausoleum of legacy piston airplane boneyards . . .