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Lycoming io390


ESPN168

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Let’s look at what some people had to say in the past...

https://mooneyspace.com/search/?q=Io-390 io390

Essentially, it is an improvement over the previous design... but is it worth it...? 
 

if you only see an improvement in cruise climb... how much of an improvement are you looking for?

Some people like the roller bearing technology...

Other people don’t fear their cam self destructing...

What makes you ask this question?

Is it time for an OH?

Best regards,

-a-

 

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51 minutes ago, carusoam said:

Let’s look at what some people had to say in the past...

https://mooneyspace.com/search/?q=Io-390 io390

Essentially, it is an improvement over the previous design... but is it worth it...? 
 

if you only see an improvement in cruise climb... how much of an improvement are you looking for?

Some people like the roller bearing technology...

Other people don’t fear their cam self destructing...

What makes you ask this question?

Is it time for an OH?

Best regards,

-a-

 

putting in an offer for plane with 1975smoh and having heard about discussion regarding pilot might experience an engine out at one time in their lifetime...if the io390 will reduce this risk then it might be in a consideration to just get a new one from Lycoming.. what would a 390 reduced the risk of an engine out considering all is treated equal ?

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23 minutes ago, ESPN168 said:

putting in an offer for plane with 1975smoh and having heard about discussion regarding pilot might experience an engine out at one time in their lifetime...if the io390 will reduce this risk then it might be in a consideration to just get a new one from Lycoming.. what would a 390 reduced the risk of an engine out considering all is treated equal ?

Maybe... maybe not. New design vs known known. Get a glider rating instead, deal with an engine failure when and if it happens, and focus on the other stuff that causes 80+% of the fatal mishaps. Especially the pilot-caused 70+%  

https://www.aopa.org/training-and-safety/air-safety-institute/accident-analysis/joseph-t-nall-report/non-commercial-fixed-wing

-dan

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31 minutes ago, ESPN168 said:

putting in an offer for plane with 1975smoh and having heard about discussion regarding pilot might experience an engine out at one time in their lifetime...if the io390 will reduce this risk then it might be in a consideration to just get a new one from Lycoming.. what would a 390 reduced the risk of an engine out considering all is treated equal ?

When I asked Jimmy Garrison, he said there was no resale premium for an IO-390. I bought a Lycoming factory rebuilt IO-360-A3B6 which is on the type certificate (so it doesn't require an STC) and is less expensive. The most important improvement is the roller lifters which probably negate camshaft spalling and Lycoming puts that in every new and rebuilt engine nowadays so you don't have to get the IO-390 for that. Keep in mind that camshaft spalling hits your pocketbook but the engine will still run pretty well with a chewed up camshaft so it's not so much of a reliability issue.

Also, keep in mind that if that engine has flown regularly and not been kept in a region of high humidity, it may be just fine. In fact, it might be the most reliable it's ever been, right now. If it has been serviced with Camguard, that may be a plus. If it has been serviced with Aeroshell 15W-50 that may be a minus.

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With all due respect to Parker, if I had an M20J I would want an IO-360 A3B6 engine (2 separate magnetos) with roller tappets and a PowerFlow exhaust. 
Throw in 10:1 pistons and a scimitar prop and I bet you’d run nicely with an IO-390 for less money. And there’s a decent chance you’d outrun it. 

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29 minutes ago, Andy95W said:

With all due respect to Parker, if I had an M20J I would want an IO-360 A3B6 engine (2 separate magnetos) with roller tappets and a PowerFlow exhaust. 
Throw in 10:1 pistons and a scimitar prop and I bet you’d run nicely with an IO-390 for less money. And there’s a decent chance you’d outrun it. 

Didn't the 10:1 pistons have all kinds of trouble?

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4 hours ago, ESPN168 said:

putting in an offer for plane with 1975smoh and having heard about discussion regarding pilot might experience an engine out at one time in their lifetime...if the io390 will reduce this risk then it might be in a consideration to just get a new one from Lycoming.. what would a 390 reduced the risk of an engine out considering all is treated equal ?

+1 for thinking out loud...

Some people really enjoy buying a plane with a run-out motor... this way they can have some free time to decide how they will rebuild what is driving their plane...

+1 for planning on having an engine out...

Statistically everyone gets to have one.  When it happens to your new engine... they have a name for that.. they call it infant mortality...

+1 for knowing there are OWTs to go with those STCs...

Our favorite MS owner that has carried the torch for having the 10:1 CR STC... is @Sandman993 who graciously shared the decision process and the performance results... and  still has the engine set up with the 10:1 pistons... last I knew...

+1 for reading up on all the details...

Some STCs are so well written/created the product lasts longer than the STC writer.  Some STC writers have not befriended everybody along the way...

+1 for additional training, discussions, hardware...

All the additional training like a glider rating, IR, tail-dragger, and hardware like an engine monitor can help improve your performance during your obligatory engine out operation...

+1 for planning ahead...

Some of those engine outs are not related to a broken engine... break the accident chain for running out of fuel as often as possible... VFR  pilots have a tendency to run out of fuel, or fly into IMC...

+1 on getting the IR...

You have upped your game.  Like having a four wheel drive vehicle... you will still get stuck, just when you get stuck... you will be deeper in the wilderness when it happens...  

+1 on considering additional Engine performance mods...

Improving HP 10% overall can seem like a small number... For T/O performance and climb speed, the additional excess power is what is being measured... consider the Missile while buying an M20J...

+1 with all the good stuff, there is always some baggage that comes with that... an IO550 burns more fuel, chance of running out just got larger... now there are two extra cylinders and four extra plugs to cause some additional challenges...

Keep thinking... keep discussing... keep an open mind... look for the good and the baggage... keep improving...

PP thoughts only, not a CFI...

Best regards,

-a-

 

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My attempt at avoiding future cam spalling was to add the centrilube stc to the new cam at overhaul. Although the old chewed up cam didn’t really become unreliable, it did send metal fragments through the prop governor (ruined that housing $) and oil pump damage $. Those are parts you guarantee at overhaul and mine wouldn’t pass standards. Rollers are probably a good way to go, but can’t weigh in on those since didn’t go that way. 
 

Wish I could’ve talked myself into doing a dual mag setup instead of keeping the Siamese twins...research at the time seems like it would be around another 9k and I was already getting my clock cleaned pretty good with the 10.1’s and the new cam stc’s.

Been dialing back a bit on the manifold pressure lately as the da in this colder weather has been substantially in the minus and the placards are staring at me. It’s kinda cool to reduce mp back to 28” and it still scooby do’s. IMO, one would probably be pleased with the 390 as long as he or she can live with the cost... I suspect a lot of wholesale changes and hidden costs to make that work where a 360 is supposed to go.

 

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As a general rule in Lycoming angle valve engines, increased displacement is directly proportional to increased output. This is because the angle valve engine has a tuned intake, improved port and valve flow and a well optimized intake flow path.  

Expect 8% more HP from an IO390. In real world terms, the IO360 angle valve is a 195HP engine. During certification years ago, such a discrepancy was previously allowable. Today, it's not. Hence the 210HP rating (210HP is 8% more than 195HP) 

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When the 390 hit the market, the replacement cylinders were twice the cost of normal angle valve cylinders, which were twice the cost of nearly every other cylinder out there. I think someone recently said that isn't the case now, but you should check before considering the leap.

The 390 was also only approved with the Hartzell Top Prop... Which may or may not matter to you.

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I would also like to add, at previous engine overhaul by the former owner...NEY Nozzles were installed. For those unfamiliar, NEY nozzles are oiler nozzles aimed at the cam lobes to facilitate lubrication. Both the intake lobes had substantial wear and for those that don't already know, two intake lobes are double tapped as they carry intake valves of all four cylinders. Ney nozzles in my engine didn't do the trick. The FWF people maintained the centrilube system would afford me the luxury of never having to buy another cam for this engine. I'm hopeful.

 

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Neither prevents lifter face corosion and spalling, which is the real problem here


Agree if I remember right I remember a thread some time ago that this was explained to him that the centri cam would not prevent spalling. I guess we didn’t type loud enough.


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16 hours ago, jetdriven said:

Neither prevents lifter face corosion and spalling, which is the real problem here

I concur... after reading myself to sleep on the subject more than once, watch those oil samples closely for corrosive contamination, water etc, run the engine in flight minimum once a week to operating oil temp 175 degrees or better for at least 15 min. Change oil and filter 25-30hrs...  And pray... that should go a long way towards cam and lifter longevity in what seems to be one of the top weakest links in the chain. Certainly one of the most expensive, but preventable issues.

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20 hours ago, jetdriven said:

Neither prevents lifter face corosion and spalling, which is the real problem here

I just can't let this go without adding how important it is to operate the engine frequently and properly based my previous statement on the centrilube stc. Taking for granted, operating the engine regularly as a given. Also, the notion that all cams are created equally may not be accurate. Now and then, there can will be a dink in a bunch of new ones in terms of hardness. At some point I was told that putting trust in a cam that has made it to TBO once and can be used again is a viable option over purchasing new.

Just looked at some serious degradation on a couple lifters inside a big continental last week viewing through a bore scope inserted into the oil filler tube. So, while the cam placement is lower in the Conty, they aren't immune to corrosion either. There was one extended period in the mid time engine where it was dormant for an extended period.

This is a long way from the intended subject of the OP...sorry for the hijack. I'll go back to sleep now.

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Yes, if you can guarantee that the airplane has never sat more than three days since it was overhauled, you’re probably right. But we all know that real life gets in the way, and airplanes sit for two weeks or three weeks at a time, and often.   Just a few episodes of this is enough to start the corrosion process on the lifter faces which leads to pitting and then spalling, and then camshaft destruction. And then the engine has to be redone. It’s happened almost every person I know with an IO360.  Roller lifters fix this problem. I think the new DCL coated diamond lifters from Lycoming look like they will too. But a plain set of iron lifters, especially the reground ones? They’re good for 1000 hours. I mean it’s a $30,000 engine  and it just lasts 1000 hours instead of twice that. 
“fly it often” doesn't work anymore. Relic from a bygone time. 

Go look at the tools in your hangar toolbox, rust all over those. What makes you think the inside of the engine isnt doing that too? 

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One of the issues with pre-roller-lifter Lycoming engines is that the camshaft is lubricated by oil splash from the crankshaft. When the engine rpm is less than 1,000 there is not enough splash to lubricate the camshaft lobes. This is exacerbated during cold engine operation using straight weight oil. Ney nozzles are one solution, and avoiding corrosion by frequently flying is also important. But avoiding engine rpm of less than 1,000 may be important as well.

Another advantage of the A3B6 engine is the ability to replace the right magneto with an EIS-40000 electronic ignition. Electronic ignition, not only provides a hotter spark, but also allows spark advance when the manifold pressure decreases as altitude increases. This increases horsepower at altitude and likewise climb rate and airspeed. 

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