Hours on your Continental 310 hp 550 Cylinders

[carusoam]

47 minutes ago, irishpilot said:

how far on the lean side are y'all running to see less than 300 CHT?

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Fortunately/unfortunately… 

My IO550 is NA…

Typically, I am cruising above 10k’ agl on the east coast…

operating at a few °F LOP…

Maximizing fuel to noise conversion…

 

The one difference that stands out… the combination of IO550 and Mooney cowling… there aren’t any cowl flaps…

 

The one oddity… when discussing the LL conversion to its by-products… this is a temp dependent chemical reaction… where it is the temp inside the cylinder that counts….  
 

The one temperature we can measure… is on the outside of a chunk of aluminum… the CHT… 

The coolest point where rings are at risk of crud… has oil cooling being sloshed around on the back side of the piston’s skirt…

 

Not bad for 90s technology!

 

PP thoughts only, not an instrument engineer…

Best regards,

-a-

 

 

[irishpilot]

 
Cold winter days are a big factor.

I flew into Colorado Springs over Christmas break and OAT was -10F. I saw 315-330 CHT. However, ops tested that my cabin heat can't keep up with that kind of cold.

The cowling and baffling are different in a Lancair than they are in a Mooney. May be the difference in CHTs.

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[Niko182]

2 minutes ago, irishpilot said:

I flew into Colorado Springs over Christmas break and OAT was -10F. I saw 315-330 CHT. However, ops tested that my cabin heat can't keep up with that kind of cold.

The cowling and baffling are different in a Lancair than they are in a Mooney. May be the difference in CHTs.

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I’ve always been lucky with my heater. Even at 16500 I still get some pretty hot air coming out with the heater on so, normally Im fine in a t shirt and some sweat pants or jeans. 
as far as engine cooling goes, the ovation has always been an airplane that doesn’t usually come with cooling problems. 

Edited February 1, 2023 by Niko182

[Little Dipper]

1 hour ago, irishpilot said:

how far on the lean side are y'all running to see less than 300 CHT?

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On long hops I fly ROP,   On short hops I fly 24/24  between 12.8 & 13.3 gph and I would see under 300 on two cylinders.

 

[Canadian Gal]

6 minutes ago, irishpilot said:

I flew into Colorado Springs over Christmas break and OAT was -10F. I saw 315-330 CHT. However, ops tested that my cabin heat can't keep up with that kind of cold.

The cowling and baffling are different in a Lancair than they are in a Mooney. May be the difference in CHTs.

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-10F is still pretty warm.

[jetdriven]

15 hours ago, Little Dipper said:

-20 lbs on two cylinders...    I fly too much hard IFR to fart around with an engine that eats too much oil and has low compression and am not in for experimenting.     Not run like a rocket ship,  engine was never over heated, excellent mechanics,  oil changed every 25 hours, pre heated before starting cold, etc.    The top half of my first engine went much longer than this one.   I'm still wondering if this is normal for 310 hp 550 Continentals?  

   

Continental still hasn't seem to have proven themselves to have worked beyond their issues with being able to machine valves and guides properly. So at about 800 hours or so the valves to start walking around on the seats and then they have low compression. You can send those cylinders to Cunningham over at powermasters and he will rebuild them to where they will last you for the rest of your flying career.. There is also a guy next to us that has a cylinder shop that is rumored to be the same kind of reputation but I havent installed his stuff yet. 

[MooneyMitch]

1 hour ago, Canadian Gal said:

-10F is still pretty warm.

Here on the central coast of Kalifornia.................we're feeling cold as our nighttime temps are dipping down into the low 40's................spoiled we are, I say!

 

[Niko182]

17 minutes ago, jetdriven said:

Continental still hasn't seem to have proven themselves to have worked beyond their issues with being able to machine valves and guides properly. So at about 800 hours or so the valves to start walking around on the seats and then they have low compression. You can send those cylinders to Cunningham over at powermasters and he will rebuild them to where they will last you for the rest of your flying career.. There is also a guy next to us that has a cylinder shop that is rumored to be the same kind of reputation but I havent installed his stuff yet. 

I’ve heard both Gann and power masters does really good valve work and most people that have their engines make it just fine to TBo. Viktor does as well however at a hefty price.

[MooneyMitch]

10 minutes ago, jetdriven said:

You can send those cylinders to Cunningham over at powermasters and he will rebuild them to where they will last you for the rest of your flying career.

Agree............Bill rebuilt my IO-550 back in 2014.  He reworked the new TCM cyclinders prior to installation on my engine.

Regarding TCM cylinder longevity................my experience with my former Ovation..............I purchased the plane with a high time engine [about 1700 hours if I recall correctly].  The previous owner installed a new engine upon his purchase of the airplane, and flew it [LOP about 300 hours per year] all over the country and Canada for business purposes.  The engine had good quality consistent maintenance over its lifetime with the previous owner.

I in turn, added an additional 600 hours or so on that engine prior to overhaul............Same TCM cylinders throughout, never removed for overhaul.

At my visit to Powermasters during the overhaul process, one tech said he knew the engine was run LOP always, as it was super clean inside when he took it apart...............

[KSMooniac]

1 hour ago, jetdriven said:

Continental still hasn't seem to have proven themselves to have worked beyond their issues with being able to machine valves and guides properly. So at about 800 hours or so the valves to start walking around on the seats and then they have low compression. You can send those cylinders to Cunningham over at powermasters and he will rebuild them to where they will last you for the rest of your flying career.. There is also a guy next to us that has a cylinder shop that is rumored to be the same kind of reputation but I havent installed his stuff yet. 

This seems to be the consensus opinion on Beechtalk with lots of supporting data.  It doesn't matter how much you fly or how you run your engine if the valves are not installed properly, and that still seems to be the case with TCM/CMI factory cylinders.  They just don't last, no matter what the pilot or mechanic does, or doesn't do.  SOP for Powermasters is to re-work all new cylinders since it is their warranty and reputation, and then they will run just fine for a full TBO run.

[Schllc]

17 hours ago, Little Dipper said:

-20 lbs on two cylinders...    I fly too much hard IFR to fart around with an engine that eats too much oil and has low compression and am not in for experimenting.     Not run like a rocket ship,  engine was never over heated, excellent mechanics,  oil changed every 25 hours, pre heated before starting cold, etc.    The top half of my first engine went much longer than this one.   I'm still wondering if this is normal for 310 hp 550 Continentals?  

   

There is no difference in the engine. 
the stc is only a prop governor adjustment, fuel flow and different prop.
If there is a difference in cylinder life it would be luck of the draw or how it’s run. 
my two ovations were well past 1500 hours on original cylinders  and they have been flying for four and two years since I sold them. I haven’t had any issues with my turbo 550’s cylinder either.  
But obvioulsy I’m a small sample…

[Pinecone]

4 hours ago, Niko182 said:

I’ve always been lucky with my heater. Even at 16500 I still get some pretty hot air coming out with the heater on so, 

My problem is, it is aimed straight back between the seats.  So my feet and lower legs get chilly.

[T. Peterson]

4 minutes ago, Pinecone said:

My problem is, it is aimed straight back between the seats.  So my feet and lower legs get chilly.

Does it ever concern you that the fuel selector gets so hot? My wife doesn’t like cold so I run the cabin heat generously, but that durn fuel selector gets so hot I almost burn my fingers switching tanks! Makes me a little nervous but I shrug it off. If it was dangerous they would not have designed it that way?

[PT20J]

12 minutes ago, T. Peterson said:

Does it ever concern you that the fuel selector gets so hot? My wife doesn’t like cold so I run the cabin heat generously, but that durn fuel selector gets so hot I almost burn my fingers switching tanks! Makes me a little nervous but I shrug it off. If it was dangerous they would not have designed it that way?

It doesn't get all that cold where I live. But I often fly at altitudes where the OAT is freezing or below. In my M20J, I only crack the heat knob, or more commonly open it a little farther and mix with cold air to get more control. If I open it more, it gets uncomfortably warm. This is in cruise with the cowl flaps closed -- the head output is noticeably less with the cowl flaps open,

My airplane had the foam insulation on the sidewalls from the factory. When I had the interior out, I removed all the old fiberglass that they still used on the ceiling and baggage compartment and replaced it with the same foam which I bought from a MSC. I think that made a difference. My hangar isn't insulated and in the winter and it is often in the thirties (F). When I want to do some work in the cockpit, I throw a little ceramic heater in the baggage compartment on a low setting and it keeps it very comfortable inside.

Skip

[A64Pilot]

14 hours ago, PT20J said:

I don't think it's LOP vs ROP -- I suspect it's power. Run them hard and they don't last as long. Mike Busch runs pretty low power. I asked him once what power he ran and he said he had no idea but it was probably 60-65%. He just has a fuel flow that he likes to run at and watches the head temps and adjusts mixture accordingly. He summed it up with, "I'm a longevity guy, not a speed guy." The airlines used to run the big radials at around 55% rated power for economy and longevity. 

 

That’s it exactly, if your cruising at say 8,000 ft full throttle and 2500 RPM LOP your producing significantly less power than the guy who’s doing the same but running best power mixture.

So yes ROP can certainly be harder on a motor, but not because it’s ROP, but because it’s higher power.

When traveling I push the throttle open and don’t touch it again until the descent to land and I suspect I’m not the only one.

At 7 to 8 thousand feet wide open you only get roughly 22 to 23 MP.

Lycoming has put in print that for max engine longevity run at 65% or less power.

[A64Pilot]

2 hours ago, Niko182 said:

I’ve heard both Gann and power masters does really good valve work and most people that have their engines make it just fine to TBo. Viktor does as well however at a hefty price.

Gann ports and polishes, does a seven angle valve job and hones not reams the guides to very tight tolerances, he also balances everything to 1 gram.

I have one of his performance engines, a Lycoming but I suspect he build his Conti’s to just as close tolerances.

I believe it’s gotten common for good builders to take brand new Continental cylinders out of the box and rework them

[Niko182]

1 minute ago, A64Pilot said:

Gann ports and polishes, does a seven angle valve job and hones not reams the guides to very tight tolerances, he also balances everything to 1 gram.

I have one of his performance engines, a Lycoming but I suspect he build his Conti’s to just as close tolerances.

I believe it’s gotten common for good builders to take brand new Continental cylinders out of the box and rework them

How do you like your gann engine?

[A64Pilot]

11 minutes ago, Niko182 said:

How do you like your gann engine?

I’m extraordinarily impressed, but I’m a Georgia boy and have much prior knowledge of his engines, it was probably the biggest reason I bought the airplane, that and the bladders, airplane has old instrumentation and should be painted, so those turned me off, but a 500 hour Gann performance engine is hard to find. My lowest cylinder is 78/80 and that moves around, they are all pretty much nearly zero blow-by.

He doesn’t do his valve jobs, someone else does. Not that I’m a NASCAR fan but I believe that’s his background and may be where he got the guy that does his cylinder work for him.

It’s honestly the smoothest 4 cyl I’ve ever run, normally to be honest I don’t like the Lyc 4 cylinder engines very much, they are rough engines, but not this one, and with the factory injectors you can run it so lean the airplane just wallows in the air before the engine begins to stumble, I mean ridiculously lean as in stupid lean, of course there is no reason to ever run that lean but it’s interesting that it will.

The IO-540W1A5D that I built with new Millenium cylinders and Gami injectors wouldn’t run LOP worth a darn

[A64Pilot]

51 minutes ago, T. Peterson said:

Does it ever concern you that the fuel selector gets so hot? My wife doesn’t like cold so I run the cabin heat generously, but that durn fuel selector gets so hot I almost burn my fingers switching tanks! Makes me a little nervous but I shrug it off. If it was dangerous they would not have designed it that way?

The only part that’s really getting hot is the lever, the actual selector valve has cold fuel running through it and I’d expect doesn’t get even warm

[GeeBee]

10 minutes ago, A64Pilot said:

I’m extraordinarily impressed, but I’m a Georgia boy and have much prior knowledge of his engines, it was probably the biggest reason I bought the airplane, that and the bladders, airplane has old instrumentation and should be painted, so those turned me off, but a 500 hour Gann performance engine is hard to find. My lowest cylinder is 78/80 and that moves around, they are all pretty much nearly zero blow-by.

He doesn’t do his valve jobs, someone else does. Not that I’m a NASCAR fan but I believe that’s his background and may be where he got the guy that does his cylinder work for him.

It’s honestly the smoothest 4 cyl I’ve ever run, normally to be honest I don’t like the Lyc 4 cylinder engines very much, they are rough engines, but not this one, and with the factory injectors you can run it so lean the airplane just wallows in the air before the engine begins to stumble, I mean ridiculously lean as in stupid lean, of course there is no reason to ever run that lean but it’s interesting that it will.

The IO-540W1A5D that I built with new Millenium cylinders and Gami injectors wouldn’t run LOP worth a darn

I will second what AH64 said. I had a Gann built O-320B2B that was without a doubt the smoothest, best running Lycoming I ever had and it turned up more that rated power on the dyno right out of the shop. I recently flew between two Continentals he did that were really fine too. The problem with Continentals is their Zero Time prices are hard to compete with for a shop that has to buy parts on the market.

[T. Peterson]

1 minute ago, A64Pilot said:

The only part that’s really getting hot is the lever, the actual selector valve has cold fuel running through it and I’d expect doesn’t get even warm

Good point. Thank you. My wife can be as toasty as she desires and I won’t worry about that hot selector!

[ilovecornfields]

50 minutes ago, GeeBee said:

I will second what AH64 said. I had a Gann built O-320B2B that was without a doubt the smoothest, best running Lycoming I ever had and it turned up more that rated power on the dyno right out of the shop. I recently flew between two Continentals he did that were really fine too. The problem with Continentals is their Zero Time prices are hard to compete with for a shop that has to buy parts on the market.

What’s the advantage of a zero-timed engine over one from a good overhaul shop? I thought the only reason it was zero timed was because the parts came from so many different places they couldn’t put a time on it. Can’t any shop that chooses to rebuild engines to “zero timed” tolerances?

[GeeBee]

1 minute ago, ilovecornfields said:

What’s the advantage of a zero-timed engine over one from a good overhaul shop? I thought the only reason it was zero timed was because the parts came from so many different places they couldn’t put a time on it. Can’t any shop that chooses to rebuild engines to “zero timed” tolerances?

Zero time means the engine comes with a new and blank log book. Only the factory or its contracted and authorized builders can give you a zero time engine. It does not mean it is better. In fact a "field overhaul to new tolerances" like Gann does is a better engine, but it is not a zero time engine. It retains the same logbook it arrived with. What "factory zero time" does is reassure the buyer that the engine was torn apart, inspected and reassembled correctly and not by a Bubba with an A&P. I've seen field O/H that were a thing of beauty and would bring tears to your eyes, I've seen field O/H that would terrorize you just to start them. There is no such thing as "zero time" tolerances. There is new tolerances, there is overhaul tolerances, there is rejected tolerances. Most factory zero time use overhaul tolerance, but only the factory can call an engine "zero time".

[ilovecornfields]

1 hour ago, GeeBee said:

Zero time means the engine comes with a new and blank log book. Only the factory or its contracted and authorized builders can give you a zero time engine. It does not mean it is better. In fact a "field overhaul to new tolerances" like Gann does is a better engine, but it is not a zero time engine. It retains the same logbook it arrived with. What "factory zero time" does is reassure the buyer that the engine was torn apart, inspected and reassembled correctly and not by a Bubba with an A&P. I've seen field O/H that were a thing of beauty and would bring tears to your eyes, I've seen field O/H that would terrorize you just to start them. There is no such thing as "zero time" tolerances. There is new tolerances, there is overhaul tolerances, there is rejected tolerances. Most factory zero time use overhaul tolerance, but only the factory can call an engine "zero time".

So you’re basically paying for a blank logbook?

[jetdriven]

Yes, the only difference in a FOH and a Factory reman is the zero time log book.  There are several shops that can build a great engine but only the MFR is allowed to call it zero time.