Everyone has a Different Break-in Procedure. What’s Yours?

MBDiagMan

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About to get my freshly overhauled O200A in the 140. It will have spanking new cylinders.

What is your favorite break-in procedure and advice?
 
About to get my freshly overhauled O200A in the 140. It will have spanking new cylinders.

What is your favorite break-in procedure and advice?
What do the people who did the overhaul say to do?
It will probably be the advice given above, but with more detail, such as avoiding prolonged idle until it is broken in.
 
Fly it like you stole it..
OK, I have no idea. With cars, it's usually a good idea not to just cruise along at the same load/rpm for the first couple thousand miles. How that translates to aviation, I have no idea. Looking forward to reading the advice from those who know.
 
Not really difficult. At least 75 % power, stay low (1,000 ft), keep temps cool as possible, vary the power from high to low, minimize low power descents. Broke in 2 engines in the last 10 years and both hardly use oil and are 77 + on compressions.
 
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I'd follow TCM's recommendations or the over haulers if they are providing a warranty on the engine. Western Skyways gave me a sheet with essentailly the same thing that I followed so I didn't void the warranty.

==========================

Engine Break - In Teledyne Continental Motors, Inc. Recommended Break-in Flight Tips:

1.Conduct a normal take-off with full power full rich conditions and monitor the engine RPM, oil pressure, cylinder head temperatures and oil temperatures.
2.Reduce to climb power in accordance with the flight manual and maintain a shallow climb attitude to gain optimum air speed and cooling.
3.Level flight cruise should be at 75% power with best power or richer mixture for the first hour of operation.
4.The second hour power settings should alternate between 65% and 75% power with the appropriate best power mixture settings. Vary the power setting every 15 to 30 minutes utilizing best power settings. Best power mixture settings are necessary to maintain high cylinder combustion pressures.
5.Engine controls or aircraft attitude should be adjusted, as required, to maintain engine instrumentation within specifications.
6.The descent should be made at low cruise power settings with careful monitoring of engine pressures and temperatures. Avoid long descents with cruise RPM and manifold pressure below 18 In. Hg. If necessary, decrease the RPM sufficiently to maintain manifold pressure.

Best power mixtures occur between 75 and 125 ̊F rich of peak exhaust gas temperatures. Mixtures richer than best power actually reduce cylinder pressure sand cylinder temperatures and can increase the time required to properly seat the piston rings. Best economy mixture settings reduce cylinder pressures and should be avoided. Reduced cylinder pressures with increased cylinder temperatures can result in “glazed cylinder walls,” which can only be corrected by removing the cylinders to re-hone the barrels and replace the piston rings.

====================================

Cheers,
Brian
 
Just broke in the engine on my arrow 3. I flew it wide open throttle and only used RPM to change power. Full mixture. Stayed below 4,000 feet
 
Just broke in the engine on my arrow 3. I flew it wide open throttle and only used RPM to change power. Full mixture. Stayed below 4,000 feet
You wasted a lot of fuel to do nothing.
 
Okay, use Superior’s break in procedure then...:)

http://www.superiorairparts.com/downloads/serviceletters/L96-08.pdf

Cheers,
Brian
  • Continue flying at 65-75% power with mixture adjusted to approximately 75°F rich of peak EGT on subsequent flights until rings have seated, oil consumption stabilizes, and cylinder head temperatures drop. This is a sign that the cylinders are broken in. Refer to Pilots Operating Handbook for leaning with fuel a flow meter or leaning without fuel flow or EGT meters.

    That will happen in about 5 minutes with the new cylinders
 
About to get my freshly overhauled O200A in the 140. It will have spanking new cylinders.

What is your favorite break-in procedure and advice?
Following the manufacturer’s directions.
 
Most I’ve read before ‘breaking in’ my factory new IO-390 is that the bulk happens in the 1st few hours, <5 or so. I flew higher power, low altitude, on the rich side, watching CHTs. Mine had also flown over 1 hour by the installer, so there’s that, plus some time on the Lycoming ‘test stand’. This included a very early ‘mineral’ oil change(mineral oil continued), 1.5 hour point.

Did I fly/break-in my engine ‘correctly’? That somewhat depends on who you ask.
 
Just fly it normally, staying within landing distance/altitude from an airport as much as possible for the first few hours. I always figured the break in instructions are at least 90% OWTs, won't do any harm but probably not do much good. Did airlines have a special break in procedure back when they flew recips?

For a good laugh about break in (not aviation or engine related), see this:

https://www.mojo-audio.com/blog/breaking-in-cables-and-components/
 
  • Continue flying at 65-75% power with mixture adjusted to approximately 75°F rich of peak EGT on subsequent flights until rings have seated, oil consumption stabilizes, and cylinder head temperatures drop. This is a sign that the cylinders are broken in. Refer to Pilots Operating Handbook for leaning with fuel a flow meter or leaning without fuel flow or EGT meters.

    That will happen in about 5 minutes with the new cylinders
Here we go again :rolleyes:

While break-in often happens quickly, sometimes it doesn't. Follow the instructions given to you. Us people on the internet won't replace your cylinder if you follow our advice and it is wrong!

Please see this thread:
https://www.pilotsofamerica.com/com...broken-in-properly.117955/page-2#post-2707997
 
Just fly it normally, staying within landing distance/altitude from an airport as much as possible for the first few hours. I always figured the break in instructions are at least 90% OWTs, won't do any harm but probably not do much good. Did airlines have a special break in procedure back when they flew recips?
Run it like you normally would? You willing to put up $12K for a new set of cylinders on an IO520 with that advice (or $4K in the OP's O200)? Running an engine LOP at 65% power (which is where I "normally" ran my Bonanza) right after over haul is the worst thing you can do to the cylinders, but hey, it's your money and plane do as you see fit. I'd rather follow the guidance from the manufacturer who holds the warranty and also a bit from Mike Busch at Savvy Mx, which is close to what the OEM outlines: https://www.aopa.org/news-and-media/all-news/2019/january/pilot/savvy-maintenance-breaking-good

Run it hard out of the gate, ROP while keeping cylinder temps below 420 (Conti) or 440 (Lycoming) is the bottom line with new cylinders.
 
Run it like you normally would? You willing to put up $12K for a new set of cylinders on an IO520 with that advice (or $4K in the OP's O200)? Running an engine LOP at 65% power (which is where I "normally" ran my Bonanza) right after over haul is the worst thing you can do to the cylinders, but hey, it's your money and plane do as you see fit. I'd rather follow the guidance from the manufacturer who holds the warranty and also a bit from Mike Busch at Savvy Mx, which is close to what the OEM outlines: https://www.aopa.org/news-and-media/all-news/2019/january/pilot/savvy-maintenance-breaking-good

Run it hard out of the gate, ROP while keeping cylinder temps below 420 (Conti) or 440 (Lycoming) is the bottom line with new cylinders.
This isn't a 0-520. This is a 0-200 with Superior standard steel cylinders with cast iron rings with 1 top chrome ring. This ring/cylinder combination the rings will be seated, oil consumption stabilized by the time you get to pattern altitude. Running hard and hot simply removes the temper from the rings, then they simply loose their tension to the cylinder wall and their ability to do thier job.
And that is what causes you to think the cylinder is glazed.
 
I like to follow the recommendations of the overhaul shop
probably not bad advice....;) Also, do a "gradual" climb....no nose high attitudes till it's broken in.

If you had an engine monitor.....it happens when the CHTs drop 20-30 degs. I ran mine at +75%HP and CHTs below 400. Once the rings set the temps dropped down to 370's....and it took my Nickels about 35 minutes to get there.
 
TCM didn't build these cylinders. (Superior did).

Well that certainly changes everything. Maybe one can copy the break in from the company Superior copied the cylinder from. Just saying.
 
RTFM. Follow the rebuilder's instructions. The usual instructions are to run the engine hard during the initial hours, minimizing idling or low-rpm operation until the rings seat properly and oil consumption stabilizes. Doing crash and dash with a new engine would be a good way to ruin it. Same thing for a new cylinder, too.

I've generally found that break-in occurs within an hour or so. Quite a bit of oil consumption during the first flight of 60-90 minutes, then almost no oil consumption after that. That's usually a good sign of break-in. I've never had an issue with break-in on a half-dozen single cylinders and one rebuilt engine.
 
What is your favorite break-in procedure and advice?
Break-in procedures aren’t something you should just experiment with. Go by the manufacturers or overhaul shop recommendations by engine type, even though it’s pretty similar across the board. Lots of money you’re playing with.
 
One must remember all the companies must deal with the CYA thing, If they went with the wild new breakin procedures, all the old timers wouldn't believe it and the lawyers would have a Field day.
 
One must remember all the companies must deal with the CYA thing, If they went with the wild new breakin procedures, all the old timers wouldn't believe it and the lawyers would have a Field day.

Huh?
 
One must remember all the companies must deal with the CYA thing, If they went with the wild new breakin procedures, all the old timers wouldn't believe it and the lawyers would have a Field day.
So what's your point? Are you telling the OP not to follow the instructions given to them?
 
My point is simple, what we did in the 30's isn't the way we do things now
I don't believe Lycoming's and Continental's break-in service letters are dated from the 1930s. The ones I used were no more than a few years old, and when I followed them to the letter the engines used almost no oil and still had high-70s compression 2000 hours later.
 
One of the Pitts S-S's I had awhile back got the new cylinders broke in with a nitrous kit :)
For real!
It was in the logs fresh top overhaul and nitrous oxide kit added :D
 
Break-in procedures aren’t something you should just experiment with. Go by the manufacturers or overhaul shop recommendations by ENGINE type, even though it’s pretty similar across the board. Lots of money you’re playing with.

Not mention differences between cylinders.

Also, for NA engines, those in Denver might want to follow different instructions than those in Florida in regards to altitudes and time to expect it to be broken in.


Tom
 
My point is simple, what we did in the 30's isn't the way we do things now
We still follow instructions for break in, as provided by the engine manufacturer or the entity who did the overhaul.
 
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