Field overhaul on my IO-540's?

stratobee

Cleared for Takeoff
Joined
Dec 18, 2011
Messages
1,112
Display Name

Display name:
stratobee
I'm not new to twin ownership, but I am new to my Aerostar. I got it cheap, knowing the engines were run out. In California where they levy a 9% user tax when you buy, it makes more sense to get in cheaper then upgrade then buy all dolled up. Engines are 300hrs over TBO. This doesn't scare me per se, and I fly it (as they don't make metal), but they do burn oil. Which would suggest the tops are bad, as they engines are clean and have no oil leaks. However, it doesn't make sense to do a top overhaul on a 2100hr engine.

I have gotten some quotes in, one from Heart Of Texas Engines for $21995. As I understood it, this included all accessories and the mags, but with overhauled cylinders and reusing as much as possible after NDT. Turbos obviously not included. This is a nice price, but I was wondering if there are some mom & pop A/P shops that have even less overhead and can offer a lower price? I want to avoid big shops if I can.

Does anyone have any recommendations in this regard where I could get a quote in? I'm based in So Cal, so ideally some leads on the west coast would be great. I would be willing to owner assist if this helps the price come down.
 
Last edited:
You've got some high power engines that are known for being worked hard. I'm assuming you want the overhaul to last a long time, like to TBO and beyond..

A mom-and-pop shop can do a good job, but it will reduce your resale value and you may or may not have good results. The variety is huge. When I'm looking at a plane, I pay attention to who did the engines and what limits they were overhauled to. You want new limits like we had our 520s overhauled to.

You also want new factory cylinders. New Lycoming cylinders virtually always make it to TBO without problem. I haven't seen an aftermarket Lycoming cylinder that's worked very well, especially on a high-power Aerostar engine.

Your exhaust is a potential area of headaches, as are turbos.

There was a local Aerostar owner (600A) who insisted he was better off with a low-cost overhaul. Within a few hundred hours, compressions were all low, engine leaking oil...

I'd be glad to talk to you on the phone if you're interested in my experience (I know a few things about these engines), but I would look at one of the shops that is experienced and specializes in turbocharged engines. I would also look into a factory overhaul. Yes, up front cost is more, but long term cost is definitely lower with a good overhaul.
 
Yon only get what you pay for -maybe. The parts and vendor services to do those 540's COSTS us over $20K with no labor, overhead or warranty figured in. Charlie Melot Zephyr Engines
 
Yahbut you make it up on volume.:p

Yon only get what you pay for -maybe. The parts and vendor services to do those 540's COSTS us over $20K with no labor, overhead or warranty figured in. Charlie Melot Zephyr Engines
 
Yon only get what you pay for -maybe. The parts and vendor services to do those 540's COSTS us over $20K with no labor, overhead or warranty figured in. Charlie Melot Zephyr Engines

A good data point, and about what I'd figure.

Another good data point: we chose Charlie for the 520s in the 310. 65-70 hours on them and very happy with the results thus far.
 
I don't think I could do it for that price either,

And I second replacing the cylinders with OE new
 
To OPs actual question, here are some data points I have:

Ben at KAJO makes a good engine, but he is a small shop and can get backlogged easily, particularly on two engines at once:

http://www.coronaengines.com/overhaul.html

If you know enough about engines to ask for specific limits and parts to be replaced, you can do well at One Stop in Oceanside. If you ask them to make you the cheapest possible overhaul, they'll do that too -- and I think it has earned them a subpar reputation. Apparently not a lot of people ask for the gold-plated overhaul, but rather the MOH-to-sell-it overhaul. The only set of 20-over cylinders I've seen on a running engine came from there :)

Tims in LGB is good, but very slow AND expensive.

We have had difficulty getting warranty support from Performance at POC.

$0.02

- Mike
 
Thanks Mike and others.

I would love to do a factory reman, but I honestly don't know how anyone can afford to do so. List price is $43K/engine. On top of that you're gonna spend $10K for hoses and lifting it in and out as well as another $10K to overhauling the turbos. Maybe there are people who can afford $110K for an engine overhaul, but I certainly am not one of them. And if I were, I'd put that money on the purchase price and get a much better equipped aircraft with engines already O/H'ed.

I will have to find cheaper solutions and so far Hearts Of Texas sound like the most competitive. I'm waiting for quotes from Corona and I will look into Oceanside.
 
To OPs actual question, here are some data points I have:

Ben at KAJO makes a good engine, but he is a small shop and can get backlogged easily, particularly on two engines at once:

http://www.coronaengines.com/overhaul.html

If you know enough about engines to ask for specific limits and parts to be replaced, you can do well at One Stop in Oceanside. If you ask them to make you the cheapest possible overhaul, they'll do that too -- and I think it has earned them a subpar reputation. Apparently not a lot of people ask for the gold-plated overhaul, but rather the MOH-to-sell-it overhaul. The only set of 20-over cylinders I've seen on a running engine came from there :)

Tims in LGB is good, but very slow AND expensive.

We have had difficulty getting warranty support from Performance at POC.

$0.02

- Mike

We just sold a plane with a corona engine on it. It took the two years parked before we bought it no worse than any other, and better than some.
 
What were the O/H cost estimates that you used when making the decision to buy a run-out?

Thanks Mike and others.

I would love to do a factory reman, but I honestly don't know how anyone can afford to do so. List price is $43K/engine. On top of that you're gonna spend $10K for hoses and lifting it in and out as well as another $10K to overhauling the turbos. Maybe there are people who can afford $110K for an engine overhaul, but I certainly am not one of them. And if I were, I'd put that money on the purchase price and get a much better equipped aircraft with engines already O/H'ed.

I will have to find cheaper solutions and so far Hearts Of Texas sound like the most competitive. I'm waiting for quotes from Corona and I will look into Oceanside.
 
I estimated about $50-60K based on loose quotes, deferring turbos. They're in OK shape. But this doesn't mean I have this saved...:D

I don't want to finance aircraft and this is a good way for me to upgrade as I earn the money, rather than owe some bank for it. Any financing would cost at least $50-100K over a 10 year period in interest, negating any savings/deals one might do on engines already being O/H. Add to this California's 8.75% User Tax on top and this makes more sense for me. Pay as you earn. I dislike debt.

As for Aerostars - they fly fine on one engine. Granted, what they don't do that well is fly on one when you lose one during takeoff. Need to get to blue line, feather and raise gear pretty quick to eke anything out of it. At least the heavier 601P. The gap between Vmca and blue line is over 20kts and it takes a long time for the speed to build between those two numbers. Once you get above 110kts, they climb at 2000fpm.
 
Last edited:
Understand in California the County that your plane is registered in sends you a paper every year asking about engine times, any radio upgrades etc. they will raise your tax on it if you are honest. If you lie and they catch you, we'll let's say it is not so pretty. In Ventura County it is not too uncommon for a call from the tax man to say he will be meeting you at the airplane next week, bring all logs.
 
Last edited:
Understand in California the County that your plane is registered in sends you a paper every year asking about engine times, any radie upgrades etc. they will raise your tax on it if you are honest. If you lie and they catch you, we'll let's say it is not so pretty. In Ventura County it is not too uncommon for a call from the tax man to say he will be meeting you at the airplane next week, bring all logs.

And that makes reason # 783271 for NOT living in California..:nonod::hairraise:
 
That's true. But the yearly luxury tax to the Board Of Equailzation is manageable. I don't know exactly how much it is per year, but probably below $1K. My old plane was exempt as it was so old and was displayed 12 times a year. It's the one time sales tax on the purchase price that's the killer. State of California is insane, but I like the place so whaddya gonna do?:mad2::rolleyes2:
 
Last edited:
An Aerostar is not the plane you want to lose an engine in.:no::nonod::(

Very true, my primary flight instructor was killed in an Aerostar that lost an engine just after rotation. The torque from the good engine rolled it on its back and that was the end of that.

Very sobering when you read that the guy that taught you bought it.
 
I'm sorry to hear that. This is however true for almost all twins.
 
There's two major elements to the overhaul. Materials, and workmanship. If Charlie has +$20k into the materials, and you use the same materials he does, then it comes down to who can put the bits in the right place correctly. I guess I would find an individual who has at least 10 or so rebuilds under his belt, and all of them are still working. Experience counts for something in this work.

Most of the planes I few were field OHs, and I never had a worry about them. not sure if a factory or big name shop would be better, but they generally have a reputation to maintain.
 
I have seen plenty of good engines from Pacific Continental at Whitman.

And I agree with living in California. I live in Camarillo and there is no place other that I would want to live.
 
Last edited:
Thanks - my mechanic mentioned Pacific Continental as well. Will check with them.
 
Thanks Mike and others.

I would love to do a factory reman, but I honestly don't know how anyone can afford to do so. List price is $43K/engine. On top of that you're gonna spend $10K for hoses and lifting it in and out as well as another $10K to overhauling the turbos. Maybe there are people who can afford $110K for an engine overhaul, but I certainly am not one of them. And if I were, I'd put that money on the purchase price and get a much better equipped aircraft with engines already O/H'ed.

I will have to find cheaper solutions and so far Hearts Of Texas sound like the most competitive. I'm waiting for quotes from Corona and I will look into Oceanside.

From your post here, it sounds like you're on the budget plan. So I'll give you the following recommendations and then bow out. I think you're on the path for expensive ownership experience.

If your engines are still within limits (compressions good, oil consumption decent, minimal leaks, oil pressure good, etc) then just keep on flying them. If you are thinking the engines need to be topped, then either re-ring them or buy 12 new Lycoming cylinder kits and throw them on. Then when you do your overhaul, you'll already have good cylinders you can use.

You will waste your money entirely if you do a bargain overhaul on an Aerostar, and you would be far better off waiting and saving some more so you can buy a good overhaul.

If you do a bargain overhaul, you will end up paying the price difference later in higher maintenance costs and other problems. Charlie's numbers give you a good reference for what you should be looking at cost wise.

And as another data point, my former boss who has a Navajo and is an A&P (ie free labor) and will always go for the low cost item for higher labor only buys factory overhauls for his Navajo. Throws them on, doesn't touch them for 1,800 hours, sends them back again.
 
Last edited:
Whatever you decide - an overhauled cylinder on these engines is a bad decision.

These are high dollar maintenance machines. Buying a run out to save money is overlooking the fact that all the accessories and hoses are likely to be run out as well. I can easily see each nacelle costing you $50K in the first 3 years.
 
I will keep flying them for a little bit, but they do burn oil. About half a qt/hr. It's not leaking, it gets burned. This tells me the rings and the valves and valve guides are bad. I thought about a top overhaul, but at these high times it doesn't seem like a sensible plan. Better to O/H. Engines don't make metal, so the bottom is probably still OK. I'd have to pull a few cylinders and have a look at the cam to see if there's any spalling or corrosion to be extra sure. I should probably do that regardless.

But it's a thought - do a top overhaul with new cylinders and then do the bottom down the line. It just feels like I will pay the mechanics twice then for essentially the same work.
 
Last edited:
I will keep flying them for a little bit, but they do burn oil. About half a qt/hr. It's not leaking, it gets burned. This tells me the rings and the valves and valve guides are bad. I thought about a top overhaul, but at these high times it doesn't seem like a sensible plan. Better to O/H. Engines don't make metal, so the bottom is probably still OK. I'd have to pull a few cylinders and have a look at the cam to see if there's any spalling or corrosion to be extra sure. I should probably do that regardless.

But it's a thought - do a top overhaul with new cylinders and then do the bottom down the line. It just feels like I will pay the mechanics twice then for essentially the same work.

Who overhauled the engines last time they went through? Have you done a wobble check? What are the compressions? What kind of cylinders are they? First run? When were they installed?

Have you dealt with many overhauls and seen the outcomes from a cut rate job? It involves paying mechanics many times over for the same work, and usually expensive work.
 
Compressions are all in the mid 70's except for one that's just barely 70. Strange thing is that 4 cylinders on each engine are chrome cylinders, so they must have been replaced at some point. Or maybe it got O/H with chrome and the metal cylinders are the ones that got replaced. Logbooks are mostly hand written with very bad hand writing, so it's hard to read. O/H was done in 1983's, so that's also something not speaking in favour of just a top overhaul. It should be taken apart.

I've not done full O/H before, but I have done a few top O/H.
 
Last edited:
I think Ted is onto a good plan that compromises equity and safety, if there is such a thing. Maybe do six new jugs on one side and see how the plane reacts. If your oil consumption goes down as expected, and you aren't making metal on the bottom end, you can fly for a while. When the engine comes off for MOH, just hone and re-ring the jugs that you have and put them back on. Remember, there is no set statement about what SMOH means. Although your jugs and pistons will not be new, they will be in limits and that's all the general term means.

The TBO of the whole engine is based on the TBO of some of the major wear components like the exhaust valves and rings where most of your oil is getting through. It's more than probable that your crankshaft is well within tolerance on the bearings and could go another 1000 hours. Of course, you still have the hoses, turbos, mags, and acc to deal with but at least your not splitting the cases yet.

Edit: I guess I'd also like to know how you operate this hi perf beast? Are you running it as fast and hard and hot as possible, or do you loiter around at 55% power, up high and cool? That will make a potentially large difference in how I would approach the deal.
 
Last edited:
I would love to do a factory reman, but I honestly don't know how anyone can afford to do so. List price is $43K/engine. On top of that you're gonna spend $10K for hoses and lifting it in and out as well as another $10K to overhauling the turbos.

Most of the lycoming remans come with an overhauled turbo, controller and the exhaust components up to the turbo. That is why they are so sinfully expensive. So unless you know 100% that your exhaust components are good, going with the 'expensive' reman that includes the components can be 'cheaper' than buying the components piecemeal at $3000 increments.

There is a reason that the Navajo is the only old twin that you can actually sell and dont have to give away for free.
 
Compressions are all in the mid 70's except for one that's just barely 70. Strange thing is that 4 cylinders on each engine are chrome cylinders, so they must have been replaced at some point. Or maybe it got O/H with chrome and the metal cylinders are the ones that got replaced. Logbooks are mostly hand written with very bad hand writing, so it's hard to read. O/H was done in 1983's, so that's also something not speaking in favour of just a top overhaul. It should be taken apart.

I've not done full O/H before, but I have done a few top O/H.

So it sounds like a field OH done before with a few new cylinders along the way, currently with good compressions and just burning some oil. That is probably an oil control ring, maybe valve guides. You do want to check the valve guides, but if you're having no morning sickness then you're probably fine.

Given what you've told me, I would likely keep flying it with just dumping oil in and save up money to do a factory remans in a few years, provided you don't have any morning sickness and your valves aren't wobbling. With chrome cylinders, it's probably the cylinders/rings causing the oil consumption. Do you have wide deck or narrow deck cases? Narrow decks are identifiable by the internally wrenching nuts on the cylinder bases (ie not a standard hex). A factory reman will come with a wide deck case (stronger and less prone to cracking). There will likely be a host of other little things that, if your engines haven't been home in over 30 years, will get improved when you hang them back on.

Edit: I guess I'd also like to know how you operate this hi perf beast? Are you running it as fast and hard and hot as possible, or do you loiter around at 55% power, up high and cool? That will make a potentially large difference in how I would approach the deal.

Since he's the new owner, I'd rather know how the previous owner flew it.

Balancing equity and safety is very doable. We do it with the 310 and did it with the Aztec. High dispatch reliability and (relatively) low costs.

Most of the lycoming remans come with an overhauled turbo, controller and the exhaust components up to the turbo. That is why they are so sinfully expensive. So unless you know 100% that your exhaust components are good, going with the 'expensive' reman that includes the components can be 'cheaper' than buying the components piecemeal at $3000 increments.

There is a reason that the Navajo is the only old twin that you can actually sell and dont have to give away for free.

Exactly. This, to me, is the biggest reason for sending a turbo Lycoming to the factory for a reman.

And this is from someone who's really not a fan of Lycoming - there's a reason why we kept the plane with Continentals.
 
Thing is, the Aerostars don't come with a TIO-540, they come with a IO–540 that has been turbonized by Ted Smith Aerostar as an STC and part of the certification. Everything after the engine, including the exhaust, is a separate system than what Lycoming provides. The Aerostars have Machen inconel exhausts and RayJay turbochargers. Don't know who originally made the wastegates, but they're now made by Aerostar Aircraft Corp, who owns the TC for the Aerostar.

I fly very low power settings mainly - long range cruising at 55%.

I failed to mention - the engines don't make any metal, except for higher chrome values. Which tells me the chrome cylinders are shedding. Hence why I'm eager to get rid of them.
 
Last edited:
Thing is, the Aerostars don't come with a TIO-540, they come with a IO–540 that has been turbonized by Ted Smith Aerostar as an STC and part of the certification. Everything after the engine, including the exhaust, is a separate system than what Lycoming provides. The Aerostars have Machen inconel exhausts and RayJay turbochargers. Don't know who originally made the wastegates, but they're now made by Aerostar Aircraft Corp, who owns the TC for the Aerostar.

I fly very low power settings mainly - long range cruising at 55%.

Depends on the Aerostar. Lycoming built both complete packages and naturally aspirated engines designed for the kit to be bolted. I'd forgotten to ask which one you had, now we know.

That does remove the turbo side benefit to a factory reman, but the other benefits are still there. This engine still runs hard.

I maintain my suggestion of make sure the valves are good and keep flying until you can afford a GOOD overhaul. If nothing else, you will likely have a bunch of other airframe expenses in the next year.
 
Thing is, the Aerostars don't come with a TIO-540, they come with a IO–540 that has been turbonized by Ted Smith Aerostar as an STC and part of the certification. Everything after the engine, including the exhaust, is a separate system than what Lycoming provides. The Aerostars have Machen inconel exhausts and RayJay turbochargers. Don't know who originally made the wastegates, but they're now made by Aerostar Aircraft Corp, who owns the TC for the Aerostar.

Hence the word 'most'.

In a way you are better off then. That advantage of the factory overhauls/remans doesn't really have any bearing on your decision.

You mentioned heart of texas engines earlier. On beechtalk, someone chronicled his dealings with this particular shop and the principal behind it. While the thread also had some posts from people who were happy with his work, well, you probably should read it before you send your engines and your money.

Have you talked to your A&P whether he is comfortable to put his name under an extensive 'repair' involving 6 cylinders of an engine overhauled when Reagan was president ? I know, there is no hard rule under part 91 of when you have to overhaul, but still, someone has to put his 'return to service' into your logs.
 
Tried to sign up to Beechtalk, but they ask you what you fly and I put "Aerostar" in there and haven't heard a word since. Maybe they only allow Beech owners to sign up.
 
Tried to sign up to Beechtalk, but they ask you what you fly and I put "Aerostar" in there and haven't heard a word since. Maybe they only allow Beech owners to sign up.

There are Aerostar folks over there. Maybe check your spam folder for approval. Not sure how long it normally takes...
 
Tried to sign up to Beechtalk, but they ask you what you fly and I put "Aerostar" in there and haven't heard a word since. Maybe they only allow Beech owners to sign up.

Lots of aerostar defectors over there :D

There are two people who own the site, they just have to get around to approve your signup. They insist on real names.
 
In Ventura County it is not too uncommon for a call from the tax man to say he will be meeting you at the airplane next week, bring all logs.

What if you don't bring them because you lost them in your safe deposit box? The plane is worth a ton less without logs right :confused:
 
Based on how you fly the plane, I think I'd go with the jugs on the engine that is using most oil and solve that problem. However, I'd also have a look at the turbo in case you are loosing oil through the shaft seal on that.

The simple, and modestly effective way to test that is to take the oil return line from the turbo off and block it, then take the supply line to the turbo off and supply about 15-20PSI of oil to it, and see if the seal seeps. No, this is not the way it 'should' be done, but yes it will give a general indication of the seal and shaft condition. If you get seeping on the hot side, just bite the bullet and have it rebuilt.

I don't know why the turbo rebuild should be so costly. Auto turbos are rebuilt for under a grand all the time, and that includes a balance. I'm sure there are hot section inspections on the aviation turbo that are not on the car, but still, it can't be that bad, and I'm a real stickler for paying 5X the cost to a shop just cause it's used on a plane.

As for the rest of the exhaust stuff, I'd do IRAN on that. Lots of still good parts on these costly engines get replaced whether they show need or not. It's easy to say just do the whole thing, but there's the aspect of infant mortality, or getting a part that is worse than the one in service, which has happened to me before.
 
Turbos are about $2K each to get O/H. There are two on each engine. Yes, we did inspect the turbos on the annual and there's the slightest oil leak, but nothing really to worry about for now. The reason they need to be done at some point is that they run out of steam to provide good MAP and keep the cabin pressurised at altitude.
 
To jump on Ted's comments

When we brought our Navajo onto our 135 ticket we got one with timed out everything, and replaced every life limit part. Coming up on 500 hours now and the thing has been almost 100% trouble free. We did loose a fuel pump a couple hours after the end of the 100hr warranty, but poop happens there. Including the money spent getting the plane up to snuff, this 500hrs has cost less in maintenance than the last one, where the owner looked for the cheapest way to fix something.
 
Back
Top