Buying engine parts in lieu of saving $?

[ragedracer1977]

Well, not in lieu of, but as well as.  I know I'm going to need a rebuild eventually, flying 2-300 hrs a year.  Is there pieces I can buy and store for when that day comes?  I've rebuilt a dozen car engines over the years, but I have a feeling it's not as easy as going online at summit racing and ordering.  

What usually gets replaced in an overhaul? 

Edited June 25, 2018 by ragedracer1977

[MB65E]

Hi! Good approach!

I had a 1200 hr io-360 overhauled in 1985. The only internals that were worth saving this last time around was one rod, the accessory case, oil sump and crank. Everything else was shot. Used serviceable cases tend to be hard to come by. The rods and rod bolts tend to always need replacement. The rod bolts are tricky because there are about 3 different versions. Your accessory case and oil sump will probably need machine done, so a spare with the machining done already might help.  You could buy ring kits, bearing kits, I would keep track of all the lot numbers and S/Ns.  Track down a set of cylinders with Known total time. So many components, the TT is no longer tracked. Build it like a race car engine and you shouldn’t have any issues. Lycoming holds their distribution close so there are only a handful of distributors. Aviall and Spruce are the two major places where I get parts from. I would even buy a new cam shaft. You do run the risk of having issues with warranties expiring,  Service bulletins or the parts being superseded. However, I would rather them be on a shelf with others doing the testing than to find an AD issue with a part and need to tare into the engine to fix it. 

-Matt 

[RobertGary1]

So you re planning on  a field overhaul? You'll want to ensure you have a willing A&P. Most A&P's today will only send engines off due to the complexity and the expense of the manuals the FAA requires you to own to overhaul an engine. What is replaced is greatly influenced on how existing parts come back from inspection. 

 

-Robert

[Andy95W]

With all due respect to RobertGary, it's not really the complexity or the FAA.  

It's the liability insurance that skyrockets if you tell your carrier you are going to start doing engine overhauls.

[FoxMike]

One risk to buying and storing parts is the potential of an AD note applying to some of the inventory.  I think you have a reasonable plan if you start collecting maybe a year or so prior to overhaul.  

[N201MKTurbo]

Other than cylinders, if you plan to replace them, and gaskets and bearings and the other mandentory replacement items, it would be a crapshoot to pre buy anything else.

if you are going to overhaul your cylinders, you could collect cylinder parts.

[LANCECASPER]

A noble idea but I think the best thing to collect when thinking of an overhaul down the road are small pictures of Benjamin Franklin. You may not end up keeping the airplane and then you have all these parts to try to sell. Money is always the most liquid.

[ragedracer1977]

My cylinders are relatively new (350 hours or so).  My engine is a little odd and sort of hard to say just how many hours are on it.  It was remanned in 1997.  It has somewhere around 1600 hrs currently.   However...  In 2015, the case was replaced.  Don't know exactly why, the logs just state it was R&R for case replacement and a list of stuff they did when they were in there.  At that time they basically did a bottom end overhaul but did not log it as such.  It has been about 600 hours since that.  In 2016 all the cylinders were replaced with brand new ECI ( I think they're RAM now) nickel cylinders.  

So, it could be 1500 hours or 300 til I have to do something.

[EricJ]

1 hour ago, ragedracer1977 said:

My cylinders are relatively new (350 hours or so).  My engine is a little odd and sort of hard to say just how many hours are on it.  It was remanned in 1997.  It has somewhere around 1600 hrs currently.   However...  In 2015, the case was replaced.  Don't know exactly why, the logs just state it was R&R for case replacement and a list of stuff they did when they were in there.  At that time they basically did a bottom end overhaul but did not log it as such.  It has been about 600 hours since that.  In 2016 all the cylinders were replaced with brand new ECI ( I think they're RAM now) nickel cylinders.  

So, it could be 1500 hours or 300 til I have to do something.

I'm in a similar boat, in that the previous owner of my airplane had a prop strike which led to a tear down with a lot of IRAN, bearing replacement, etc., etc.   At the same time it got a new prop, overhauled governor, overhauled mag, etc., etc.   I've had the fuel servo and distributor overhauled since I got it, so it's a pretty fresh engine from some perspectives even though it is officially 1500 SMOH.  No idea how long it'll actually last, so I'm just staying paranoid about keeping an eye on it.   I've determined that my policy is just going to be to run it until it clearly needs some attention and then decide what to do from there.   The case has something like 5k hours on it, and I'll be open to every option that's available (e.g., FRM, whatever) when the time comes.   Since I've no idea what direction I'll actually wind up going, I'm not going to bother with part accumulation.   I think you need a pretty good crystal ball to know what'll need replacing and what won't, assuming a field overhaul even makes sense at the time.   There'll be a risk that you buy stuff that you don't need or can't use.   Naturally, there's risk with waiting, too, so YMMV. 

 

 

[ragedracer1977]

1 hour ago, EricJ said:

I'm in a similar boat, in that the previous owner of my airplane had a prop strike which led to a tear down with a lot of IRAN, bearing replacement, etc., etc.   At the same time it got a new prop, overhauled governor, overhauled mag, etc., etc.   I've had the fuel servo and distributor overhauled since I got it, so it's a pretty fresh engine from some perspectives even though it is officially 1500 SMOH.  No idea how long it'll actually last, so I'm just staying paranoid about keeping an eye on it.   I've determined that my policy is just going to be to run it until it clearly needs some attention and then decide what to do from there.   The case has something like 5k hours on it, and I'll be open to every option that's available (e.g., FRM, whatever) when the time comes.   Since I've no idea what direction I'll actually wind up going, I'm not going to bother with part accumulation.   I think you need a pretty good crystal ball to know what'll need replacing and what won't, assuming a field overhaul even makes sense at the time.   There'll be a risk that you buy stuff that you don't need or can't use.   Naturally, there's risk with waiting, too, so YMMV. 

 

 

Sounds like parts accumulation is not the way to go.  I wasn’t sure if it was like rebuilding a car engine and it sounds like no.  I have no clue why they replaced the case on mine, but it wasn’t due to a prop strike,  the prop is the same since the engine was overhauled.  My guess is a crack or something, but who knows.

Edited June 26, 2018 by ragedracer1977

[RobertGary1]

12 hours ago, Andy95W said:

With all due respect to RobertGary, it's not really the complexity or the FAA.  

It's the liability insurance that skyrockets if you tell your carrier you are going to start doing engine overhauls.

the overhaul itself isn’t complex but maintaining all the current manuals and keeping all the tools certified is work for someone who doesn’t overhaul engines for a living. More complex that just taking it apart and putting it back together   

 

 -Robert

[Tommy]

Would you buy all the right tool$$$, learn how to remove an appendix off YouTube, then do one on yourself? 

It is doable... 

[Yetti]

Look at it this way.   The price of a factory overhaul equals the price of a Mooney C.   Find a C with a run out engine and do a rebuild on that engine, swap to your plane, rebuild the other engine and sell the other plane with a rebuilt engine.   Minus your time it could be a break even proposition.   My plan is to keep swapping cylinders till it make metal and needs a teardown and flushing.    May be tomorrow or may be several years who knows.

 

[mooniac15u]

2 hours ago, Yetti said:

Look at it this way.   The price of a factory overhaul equals the price of a Mooney C.   Find a C with a run out engine and do a rebuild on that engine, swap to your plane, rebuild the other engine and sell the other plane with a rebuilt engine.   Minus your time it could be a break even proposition.   My plan is to keep swapping cylinders till it make metal and needs a teardown and flushing.    May be tomorrow or may be several years who knows.

 

Do you have enough insurance to cover the liability if the engine you overhaul and sell fails and results in injuries?

Personally, I don't think I would buy a plane with a "homebuilt" engine.  It's not that it isn't possible for an owner to do a quality overhaul it's just that as a buyer you have no idea of the actual quality of the work and no recourse in the event of any issues.

[Yetti]

2 hours ago, mooniac15u said:

Do you have enough insurance to cover the liability if the engine you overhaul and sell fails and results in injuries?

Personally, I don't think I would buy a plane with a "homebuilt" engine.  It's not that it isn't possible for an owner to do a quality overhaul it's just that as a buyer you have no idea of the actual quality of the work and no recourse in the event of any issues.

What I have learned following behind the decades of certified mechanics in my plane and a couple others is there are good mechanics and some that rush things and have different degrees of precision.  Most of the people that I know that work on planes are much more careful a)because their butt is on the line and b)because they are not under time constraints to make a buck.   Unless you are more involved in maintenance than signing the check for your plane, you really don't have a good idea of how airworthy the plane is. The IA and I have a good understanding that the signature is only good till the plane exits the hanger.   Since IA have no way to control how the pilot breaks in or operates the engine, warranties are limited at best. Obviously gross negligence can occur anywhere.

Edited June 27, 2018 by Yetti

[N201MKTurbo]

When I bought my first Mooney (M20F) the engine had a problem which required a major repair. I decided to do it myself. With the supervision of a certified mechanic. Well he was in the same city most of the time anyway. I was lucky because the office I was working at was 3 doors down from Superior Air Parts in Denver.

I disassembled it and sent all the parts to the appropriate shops for overhaul and inspection. I ordered all the mandatory replacement parts, painted everything and reassembled it. The hardest part was getting the correct push rods. When you rework the cases the distance from the lifters to the rockers changes. They must be within 0.020 to 0.080 of valve lash with dry lifters. Measuring the length and procuring the correct length was a PITA!

Anyway, that was the best engine I ever had. It made it to TBO with zero issues. In 86 it cost me about $7000 in parts and services.

I think you get better work done at the different shops when you are a 29 year old kid trying to fix his plane then just some random shop sending parts in.

[Yetti]

The grumpy IA has been redoing a Cherokee 180 for the last year.   He rebuilt the engine for about $11K or so.

[mooniac15u]

1 hour ago, Yetti said:

What I have learned following behind the decades of certified mechanics in my plane and a couple others is there are good mechanics and some that rush things and have different degrees of precision.  Most of the people that I know that work on planes are much more careful a)because their butt is on the line and b)because they are not under time constraints to make a buck.   Unless you are more involved in maintenance than signing the check for your plane, you really don't have a good idea of how airworthy the plane is. The IA and I have a good understanding that the signature is only good till the plane exits the hanger.   Since IA have no way to control how the pilot breaks in or operates the engine, warranties are limited at best. Obviously gross negligence can occur anywhere.

Are these the same careful owners who are making homemade jacks from wooden tabletops, conduit, and hose clamps?

If someone on MS asked for opinions on a Mooney for sale with 0 hrs since overhaul by an owner I expect the majority opinion would be to not price it as a fresh overhaul and more than likely many would recommend walking away from it.

[N201MKTurbo]

22 minutes ago, mooniac15u said:

Are these the same careful owners who are making homemade jacks from wooden tabletops, conduit, and hose clamps?

If someone on MS asked for opinions on a Mooney for sale with 0 hrs since overhaul by an owner I expect the majority opinion would be to not price it as a fresh overhaul and more than likely many would recommend walking away from it.

I would have to talk to the person who rebuilt it. They would have to convince me they knew what they were doing and they did it right. 

You don't always get that opertunity when dealing with a big shop. It’s more about the parts in the engine than who tightened the bolts. 

My current engine is a factory reman, but I found three different sized through bolts, so the case was pretty tired when it was reused. That was not captured anywhere in the engine paperwork. 

There have been plenty of people who have had issues with engines from some very well respected shops. 

BTW an owner can’t rebuild an engine. Only an A&P or repair station can rebuild an engine.

Edited June 27, 2018 by N201MKTurbo

[mooniac15u]

1 hour ago, N201MKTurbo said:

I would have to talk to the person who rebuilt it. They would have to convince me they knew what they were doing and they did it right. 

You don't always get that opertunity when dealing with a big shop. It’s more about the parts in the engine than who tightened the bolts. 

My current engine is a factory reman, but I found three different sized through bolts, so the case was pretty tired when it was reused. That was not captured anywhere in the engine paperwork. 

There have been plenty of people who have had issues with engines from some very well respected shops. 

BTW an owner can’t rebuild an engine. Only an A&P or repair station can rebuild an engine.

I think everyone here knows an owner can't sign off on rebuilding an engine...

People reporting individual issues with engines from major shops does not provide any objective measure of quality or any means of comparison with the quality of doing it yourself.  No product or service has 100% quality and unhappy customers are far more likely to speak up. If you choose a reputable shop they will stand behind their work. If you buy a plane with a one-off local overhaul it's unlikely to come with a transferable warranty.  Caveat emptor.

[N201MKTurbo]

5 minutes ago, mooniac15u said:

I think everyone here knows an owner can't sign off on rebuilding an engine...

People reporting individual issues with engines from major shops does not provide any objective measure of quality or any means of comparison with the quality of doing it yourself.  No product or service has 100% quality and unhappy customers are far more likely to speak up. If you choose a reputable shop they will stand behind their work. If you buy a plane with a one-off local overhaul it's unlikely to come with a transferable warranty.  Caveat emptor.

Just being devils advocate here.

The longest warrantee I could find was 24 months or 36 if you use it at least 40 hours a month.

So after two years your argument doesn't hold water. My experience is that if something is going to go wrong it goes wrong rather quickly. After a few years it is more how it is operated than how it was put together.

[RobertGary1]

1 hour ago, N201MKTurbo said:

 

BTW an owner can’t rebuild an engine. Only an A&P or repair station can rebuild an engine.

Anyone can rebuild an engine. An A&P must supervise.

-Robert

[N201MKTurbo]

3 minutes ago, RobertGary1 said:

Anyone can rebuild an engine. An A&P must supervise.

-Robert

If the A&P signs it off, the FAA must assume he rebuilt the engine. He can have as many helpers as he needs.

[mooniac15u]

19 minutes ago, N201MKTurbo said:

Just being devils advocate here.

The longest warrantee I could find was 24 months or 36 if you use it at least 40 hours a month.

So after two years your argument doesn't hold water. My experience is that if something is going to go wrong it goes wrong rather quickly. After a few years it is more how it is operated than how it was put together.

Warranties in airplane engines are certainly nothing to write home about.  However, the strawman presented was to overhaul an engine and sell it more or less immediately in an M20 airframe.  Two or three years of warranty sounds a lot better than no warranty.

Would you buy the airplane with the owner overhaul rather than a comparable airframe with a runout engine where you control the overhaul process? I'm just not sure you can find a buyer that will pay enough for the one-off field overhaul to make it worth your while versus just selling it as a runout engine. Doing your own overhaul on a plane you plan to fly so you can save money and feel good about your engine is an entirely different value proposition.

[RobertGary1]

19 minutes ago, N201MKTurbo said:

If the A&P signs it off, the FAA must assume he rebuilt the engine. He can have as many helpers as he needs.

Well, specifically they will assume he personally supervised the work to the extent he felt necessary being done. Not necessarily that he touched any of it.

 

A person working under the supervision of a holder of a mechanic or repairman certificate may perform the maintenance, preventive maintenance, and alterations that his supervisor is authorized to perform, if the supervisor personally observes the work being done to the extent necessary to ensure that it is being done properly and if the supervisor is readily available, in person, for consultation. However, this paragraph does not authorize the performance of any inspection required by Part 91 or Part 125 of this chapter or any inspection performed after a major repair or alteration.

 

-Robert