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Rebuild from bare case & crank?

sbalmos

Well Known Member
Just a theoretical question... There's a possibility I can get my hands on a perfectly good bare O-320-E2D case and crankshaft. No pistons, no accessories, nothing. I seem to get vague answers on whether or not this can constitute a serviceable core to trade in.

Secondly, since it's a completely bare core, and I know which compression pistons, alternator, starter, EI, etc I want... Could I get Penn Yan or one of the other typical rebuilders to do the necessary inspection to the core and case, mount on pistons, and leave some of the accessory mounting to me?

I'm just trying to think of various ways I might be able to save money off of a normal rebuild by the fact that I know exactly what accessories I want, and the engine being a bare case & shaft.

Thanks!
 
Scott, It is like you are reading my mind. I have been looking at new engines, but the cost is so high I am looking at other options. Unlike you, I don't know all the options I want. I change my mind on fuel injection or not, piston compression, what mags, starter, etc. After reading Bob's account of the Lycoming school, I think I would enjoy that. Maybe that would give me a better understanding of the engine and help pick what would work best for me.

I do know of a "core" for an O-360 I could get for a nice price, but like you, I do not know if the cost of the overhaul makes it a good deal or not. I know there are many great "local" shops that would do as good a job as one of the big places like Penn Yan, but then there are places I read about like FWF that have bad reputations. I don't mind paying for something, but I don't want to pay twice.

I will be interested in what others have to say about you rebuilding from the core. Keep us up to date on what way you go with your engine.
 
Scott, I would take what you have any day over a complete core since having it apart allows for easy evaluation of parts. Most shops use new cylinders and pistons. Find someone local to help you with the overhaul.
 
Scott,

Send the Case to Divco, Crank to Aircraft Speciality and build up from there. You will save a TON of money. :)
 
Scott,

Send the Case to Divco, Crank to Aircraft Speciality and build up from there. You will save a TON of money. :)

Ditto. Building up a Lyc engine isn't rocket surgery. Just do your homework (like you're doing here...).

Lots of sources on parts too. Some you want new, some good/used works nicely too. $125 for a new mag drive gear?! Uh, no.
 
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I like to do it myself

Just built a IO-540 from a core.

Had the case inspected by Divco
Crank done by Aircraft Specialties
Rods by Divco
Gears magnifluxed
Lifters, plungers, and Cam re worked by Aircraft Specialties
All new Cyl, Pistions, Piston Pins, rings etc. from ECI flow matched and with my requested compression.
Rebuilt one Bendix mag
One new Lightspeed ign.
New prop governor
rebuilt fuel pump
Fuel injection rebuilt and flow checked including injectors, lines and flow divider by Airflow Performance
New bearings for crank, rods, cam
New starter


All in all including the purchase of the core and extra parts I was into it less than $30K and had the exact engine I wanted.

A new IO-540 from van is $45k+ without the governor

Your milage may vary. It is somwhat of a gamble if you dont know if the parts you are buying as a core are good.
 
engine

This is an excellent way to build an engine on a budget. I have a ready to assemble 0 320 that I got one piece at a time. Make sure the crank passes the 505 sb or that you understand the consequences if it doesn't. I bought new Lycoming cylinders which include pistons and piston pins. Lots of new small parts from ECI and Superior. My total cost will be under 15k but that is not at todays prices.
 
This is an excellent way to build an engine on a budget. I have a ready to assemble 0 320 that I got one piece at a time. Make sure the crank passes the 505 sb or that you understand the consequences if it doesn't. I bought new Lycoming cylinders which include pistons and piston pins. Lots of new small parts from ECI and Superior. My total cost will be under 15k but that is not at todays prices.

My dad has a 320 crank fresh out of Aircraft Specialties that meets the 505 sb if anyone needs one. I don't think he is looking to give it away but it is a good crank with a fresh OH and tag.
 
I'm doing the same. A local repair shop is providing me with a good O-320 E2D core for cheap. We stripped down and dismantled the engine and had everything sent out for recertification. It will have new cylinders and pistons for higher compression to make it 160hp. I am putting FI and electronic ignition on the engine, and it will have new starter and alternator.

The nice thing for me is getting to help with the rebuild so I have some working knowledge of the engine.

I'll end up with a fresh engine built with exactly what I want for way less than the cost of a new one from Van's.
 
Bruce, ypu are right about learing more about the engine by working on it yourself. I really like the school rebuild class Bob was posting about. There is no better way to know what is going on up front than building or rebuilding it. Did you just check with the local shop or look for a core somewhere else too?
 
I'm pretty sure I'm not in the mainstream on this one. I just got done overhauling a O360 in a Cherokee. I had the benefit of the Lycoming course that Bob Axsom recently wrote about - and, while it's not rocket surgery, there is enough to it that I'd be hard pressed to say to go at it without training.

Dan
 
I'm pretty sure I'm not in the mainstream on this one. I just got done overhauling a O360 in a Cherokee. I had the benefit of the Lycoming course that Bob Axsom recently wrote about - and, while it's not rocket surgery, there is enough to it that I'd be hard pressed to say to go at it without training.

Dan

And there's something to be said that there are better ways of handling overhaul tasks and techniques than the way Lycoming spells out in their classes and the OH manual. I would never dream again of putting one together with silk string but thats they way they teach.
 
And there's something to be said that there are better ways of handling overhaul tasks and techniques than the way Lycoming spells out in their classes and the OH manual. I would never dream again of putting one together with silk string but thats they way they teach.

Just did my last one with Silk thread and sealant with no leaks but I am open to better ways.

Whatchya got up your sleeve? or is it confidential?
 
I've always used the silk thread and the aviation grade permatex in the plastic bottle... let tack, lay thread. With proper case bolt torque, no leaks. :)
 
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overhaul

Just bought a O-540 A1d5 myself that had been zeroed last overhaul, logs to day one. $5500 and had Custom Airmotive fog it and install dehydrator plugs for another $100. Kind've nice to live in Tulsa and walk all the parts in to the shops you guys are talking about. I think there will continue to be good deals out there as the certified continue to shrink especially twins. I really don't need injected just to save 1-1/2 gallons per hour at 12k.

Don
 
Is a prop strike engine worth a look?

In looking for a core and at engines, there are always "prop strike" engines available. Some say checked and dialed to .001 or .002. My limited understand of engines has me thinking that if a prop strike happen, it is going to cause all kinds of problems other than just a crank. Am I wrong? Is it worth looking at an engine that has had a prop strike that has been checked and "dialed" as an engine that could be trusted without complete overhaul? Or does it only have value as a core?
 
In looking for a core and at engines, there are always "prop strike" engines available. Some say checked and dialed to .001 or .002. My limited understand of engines has me thinking that if a prop strike happen, it is going to cause all kinds of problems other than just a crank. Am I wrong? Is it worth looking at an engine that has had a prop strike that has been checked and "dialed" as an engine that could be trusted without complete overhaul? Or does it only have value as a core?

It doesn't have a core value. Lycoming says in SL250A it must meet 6 criteria to be a core, it flunks #4.

4. Operable ? The exchange engine core must have been able to operate and perform to a level that
safely permitted its use ?in flight? up to the time it was removed from the airframe. The operable
condition must be preserved until the exchange engine core arrives at the Lycoming Engines factory.
 
If it doesn't have core value, is it just a throw away at that point? What is the procedure that needs to be followed to put the engine back in service? I know it is done, I just don't know how it is done. I do not want to buy an engine that is worthless. What I really don't want to do is buy an engine that is not safe! Im all for saving money, but not at quality or risking my life.
 
It doesn't have a core value. Lycoming says in SL250A it must meet 6 criteria to be a core, it flunks #4.

4. Operable ? The exchange engine core must have been able to operate and perform to a level that
safely permitted its use ?in flight? up to the time it was removed from the airframe. The operable
condition must be preserved until the exchange engine core arrives at the Lycoming Engines factory.

I think Rockwood was talking about a core to overhaul (at least that is the way I read it). A prop strike would not necessarily rule out an engine as a "good" core for overhaul. Many, many engines with prop strikes have been returned to service. That said, there is a very real risk that the crank, case or cam won't be serviceable for any number of reasons, regardless of prop strike. If you get a core cheap enough that you can replace a major component and still be ok financially, go for it. If you are paying full core price, I would look for a deal where the seller guarantee's the crank and case. Some of the salvage yards will provide this guarantee.

As far as a prop strike being a core for a factory engine, I disagree with David. If the engine was airworthy at the time of the strike I would send it in. If a major component isn't serviceable the factory will charge regardless of a prop strike.

Just my $.02.
 
correct

Robert, you are correct. I was thinking about an overhaul if I got an engine that had a prop strike. I don't understand if when they say it dials out at specifications (.001 .002) and has been inspected according to Lycoming requirements.

I can't see any way I would even consider an engine that had a prop strike that did not have a complete overhaul. Too many things could be missed in an inspection - especially by someone trying to sell an engine. Maybe I am better just sticking with new. It is not an easy choice.
 
Core

I bought an 0320 E2D with no log books,
Only rumored to be low time. It sat for many years
unpickled. It was a risk and you don't know what you
Have until you break it all down and inspect and send the case
and all the steel parts out for magnaflux and certification with a
Yellow tag or a white serviceable tag. I lucked out and now have
a fresh rebuilt engine that I did with a local retired very experienced
AP. I ended up replacing some parts but not many. I had the cylinders
Rebuilt and bought all the parts lycOming requires of a major overhaul.
In fact it could have been certified less the piston upgrade.
I spent far less money than a new engine.

Bottom line. Buy a good core and rebuild it. Sell
The crank and case on eBay and pay for most of what the core
Would cost. With only a case and crank, buying all the other parts
Including cylinders will cost way more than a good core.
 
Just did my last one with Silk thread and sealant with no leaks but I am open to better ways.

Whatchya got up your sleeve? or is it confidential?

I've always used the silk thread and the aviation grade permatex in the plastic bottle... let tack, lay thread. With proper case bolt torque, no leaks. :)

Talk to me when your engine has 1500+ hours on it. Not a single one I've ever opened up wasn't leaking in two particular spots: 1. bottom under the main bearing and 2. on the top just forward between #3 and 4, or on a 540 5&6. These are the areas where the cases fret the most and in every instance I've found the string completely gone.

Two engines I've done with silk string 100% by the book are leaking.

I used proseal on the last two. Not a drop. I helped a friend do the heads an banks on a Merlin and thats what Nixon (shop that overhauls Merlins) recommends. If its good enough for a 100K+ overhaul...
 
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Did you just check with the local shop or look for a core somewhere else too?
I did look around online and was seriously considering getting an ECI or Superior kit to build. The guy who owns the local repair shop is a neighbor and made me an offer I couldn't turn down. He has built lots of engines and offered his labor for free - and I get to assist in the rebuild. The core engine was at 2000+ hours when it got pulled off a C-172 and replaced with a new engine. No damage. The parts all came back in spec, and he guaranteed the crank, case and cam. He provided a rear accessory case that has the correct fuel pump needed for FI. Cylinder heads also got drilled for FI nozzles. I should save well over $10K from a comparable engine from one of the usual suppliers for RV builders.

As for the silk thread discussion, he says they use and have great success with Yamabond (used on Yamaha engine cases).
 
I don't think a crank and case pair would be enough.
Just consider pricing all the little pieces, the ones you would re-use if they qualify. You need sump and accessory cases, intake tubes rocker covers oil drains accessories gears crankcase vent, mags, oil pump etc etc etc....
Even if you could get a good price on these, consider the time you will spend tracking them down, pay shipping or sales tax etc.
It's much easier to start with a whole core, which gives you something to work from.
 
I'm actually pleasantly surprised that this seems to be a popular route when dealing with engines. It's taken me another morning of re-reading the thread to digest everything.

So, for both my and Rockwood's edification, it looks like there's the following path if someone knows exactly what parts they want on the engine:

1. Get bare crankcase & shaft
1a. Get bare case and shaft outright, either by pure luck or purchasing from Divco & Aircraft Specialty or others.
1b. Buy bare core from a repair house
1c. Buy run-out engine, prop strike, some fully-built engine.
1c gets hairy in its decision tree, which I'll get to in a moment.
2. Buy up cylinders, pistons, etc from whatever sources - Spruce, eBay, ads, etc. Send for repair as necessary.
3. Build up engine on own, with A&P supervision.
3a. The kicker - Can I just buy up the parts piecemeal, send it to a repair shop, and have them build everything up, test-run it, balance, etc?

I would love to go the 3a route, where I go to a repair shop, preferably one that I buy the bare core from, and either say "here's exactly what carb, starter, mags, cylinder compressions, etc I want, get them and rebuild that engine", or more likely "Grab a core off the shelf, here's the parts, rebuild. You also supply the screws, pins, small stuff I forgot."

1c, for Rockwood I think, is the interesting part, which I was trying to avoid. When I read about normal rebuild rates from repair shops, they usually say "rebuild includes new or rebuilt carb, alternator, etc". I want to avoid buying a run-out engine, sending it in for a rebuild, and then secondly having to tear off what I don't like and replacing it with what I wanted in the first place. So in his, or maybe my, case, we could buy a normally run-out engine, prop strike, or something (from a place like Wentworth), tear off everything down to a bare case, and we're back to square one with the plans to send out the case, shaft, etc for servicing, and the existing pistons, alternators, etc that we don't want we just sell off by ourselves on eBay or such?
 
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