Lycoming O-235 initial engine break in

RyanB

RyanB

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Tomorrow evening will be my first time flying a freshly overhauled engine on a 152 (>5 hrs on it). Ive been briefed on break in procedures, (flying it wide open or no less than 75% pwr and making power changes every 15 minutes). Planning to climb to altitude over the airport if anything were to go haywire and fly along the V airway on my XC to give the most available options during cruise. Was told to let the engine cool to the touch once landed before departing again. Anything else that you all could recommend to me? Thanks!
 
You probably know this, but make sure you've got straight mineral oil in the crankcase. I did this for the first 50 hours (Aeroshell 100, 50W) and then switched to an ashless dispersant oil. Good luck!
 
As I understand you should stay below 7000 msl or so in order to maintain 75% power or something like that. Should be no problem in a 152 :D
 
Read this and do as it says in section C, flight test. Don't reduce the power in the climb; that's for larger engines. I have broken in plenty of Lycs using this procedure and they all used little oil, except for one that was used for circuit work too soon after the test flight. It needs to be flown on cross-countries for ten hours or so to get the best ring seating.

http://www.lycoming.com/Portals/0/t...ating engine Break-In and Oil Consumption.pdf
 
SoCal RV Flyer said:
You probably know this, but make sure you've got straight mineral oil in the crankcase. I did this for the first 50 hours (Aeroshell 100, 50W) and then switched to an ashless dispersant oil. Good luck!
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From what I understand, mineral oil is being used for the first 25 hours and then the break-in will be evaluated at that point.

FORANE said:
As I understand you should stay below 7000 msl or so in order to maintain 75% power or something like that. Should be no problem in a 152 :D
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I'll be at 5500' tops in cruise, she's not an IFR bird and I feel better staying VFR anyway. Depending on wx, I'm gonna try to fly her from Chatt. to GKT and back.
 
SoCal RV Flyer said:
You probably know this, but make sure you've got straight mineral oil in the crankcase.
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This has been proven wrong many times over, any good quality AD oil will work, Phillips 20W50 from day 1 to TBO.
As long as there is no anti wear additives any oil works.
 
Few people realize you make enough BMEP at idle to seat rings.
 
Tom-D said:
Few people realize you make enough BMEP at idle to seat rings.
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Sorry tom that ain't what lycoming says,
"new, rebuilt or overhauled engine should receive the same start, warm-up and pre ight checks as any other engine. There are some aircraft owners and pilots who would prefer to use low power settings for cruise during the break-in period. This is not recommended. A good break-in requires that the piston rings expand suf ciently to seat with the cylinder walls. This seating of the ring with the cylinder wall will only occur when pressures inside the cylinder are great enough to cause expansion of the piston rings. Pressures in the cylinder only become great enough for a good break-in when power settings above 65% are used. "

Bob
 
unsafervguy said:
Sorry tom that ain't what lycoming says,
"new, rebuilt or overhauled engine should receive the same start, warm-up and pre ight checks as any other engine. There are some aircraft owners and pilots who would prefer to use low power settings for cruise during the break-in period. This is not recommended. A good break-in requires that the piston rings expand suf ciently to seat with the cylinder walls. This seating of the ring with the cylinder wall will only occur when pressures inside the cylinder are great enough to cause expansion of the piston rings. Pressures in the cylinder only become great enough for a good break-in when power settings above 65% are used. "

Bob
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Lycoming was the last to admit LOP was a good method, plus they haven't re-written the that service letter since the fine hone was invented.
 
fiveoboy01 said:
My engine builder disagrees.

I'll take their advice over yours.
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Old wives tales die hard. I've built over 100 engines and have always used Phillips 20W50, never an oil related problem.
ECI delivered thousands of cylinders and has always advised Phillips 20W50. I'll bet they have better research resources than your engine builder.
 
I spent an hour and a half in a racetrack pattern over the airfield for 1.5 hours at 2500 MSL at 75% power for 10 mins and WOT for 3 minutes in my O-320, as was the procedure set forth by the engine shop that did my 3 cylinders. I then landed, the mechanics spent about 30 minutes going over the engine looking for leaks or anything out of place. I then did a 40 minute cruise back to the home drome alternating 75% power and WOT, again at 2500 MSL. After that I did a 6.5 hour day in the air doing the same thing at 5.5, until I had to clear some mountains. 75% power for 10 ish, then WOT for 3 minutes. The first 1.5 I burned a quart. The second 1.5 I burned a quart. The third 1.5 I burned almost nothing. The fourth 1.5 I burned almost nothing. Did a 40 minute hop to the airport that did the engine, and they pulled the plugs. One still showed some oil on it, so still have to fly the crap out of the engine.

Last week I did another 5.5 hours and alternated between 2500 RPM and 2650 RPM whenever I thought about it. I added 1 quart at the end of the flight day. So burned about 1 quart in 7-8 hours, which I heard is about what it should be when oil consumption stabilizes. For all of this I was at or near full rich to keep the cylinders cool, as per the engine builder.

You will not go wrong with using the manufacturer's rules. There's a reason their instructions die hard... because they work good enough for the task for a long time, and FAR more accidents occur when people don't follow the manufacturer's instructions than accidents that happen due to FOLLOWING manufacturer's instructions.

But with engine break ins, it really seems like the best advice is... open that sucker up at low altitude, pour fuel into the engine to keep the cylinders cool, and find thick air to get the pressure in the cylinders as high as possible. Especially for the first couple of hours, pay close attention to the oil gauges. And if you're not gonna stick around the airport that did the work, plan a route that gives you plenty of options.
 
Tom-D said:
This has been proven wrong many times over, any good quality AD oil will work, Phillips 20W50 from day 1 to TBO.
As long as there is no anti wear additives any oil works.
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For my engine, a straight-grade mineral oil is recommended by Lycoming for break-in, so not exactly an old wives' tale. After 50 hours, I switched to Phillips AD 20W50, and my oil consumption is now less than one quart per 25 hours. I'd say the rings have seated well by following the advice spelled out in Lycoming's manual. I can't argue with that kind of success.
 
What is the benefit of allowing the engine to cool to the touch before departing again? Giving the cylinders time to contract after expanding? Is it a necessary step to proper break in?
 
At least for big bore Continentals, the manufacturer's recommendation is mineral oil for the first 25 hours, or until oil consumption stabilizes.

That "stabilization" can occur in as few as 4 or 5 hours. In that case, the recommendation is to get the mineral oil out and the A/D in ASAP, due to the better corrosion fighting additives in the A/D oil.

Most of the above was gleaned from the Cirrus Owner's site, where the topic comes up with some regularity.
 
Tom-D said:
Old wives tales die hard. I've built over 100 engines and have always used Phillips 20W50, never an oil related problem.
ECI delivered thousands of cylinders and has always advised Phillips 20W50. I'll bet they have better research resources than your engine builder.
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How many do you think Zephyr has assembled, collectively? The head assembler alone has been putting them together for almost 40 years. Do you think Lycoming has better resources than ECI and their questionable quality cylinders? They say straight mineral for break in.

Again, I'll take their(and Lycoming's) advice over yours and ECI's.
 
Is it possible the the choice of oil is irrelevant?
But that the break in procedure is the actual important ingredient in engine longevity?
 
fiveoboy01 said:
How many do you think Zephyr has assembled, collectively? The head assembler alone has been putting them together for almost 40 years. Do you think Lycoming has better resources than ECI and their questionable quality cylinders? They say straight mineral for break in.

Again, I'll take their(and Lycoming's) advice over yours and ECI's.
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You take Charley's advice to the bank, but he'll also tell you ECI recommends 20W50 Phillips.
 
With our 150 (0-200) we ran wide open throttle 2500-2600rpm cruise the first 10 hours. Phillips 20-50 is recommended by a lot of builders. About 100 hours on engine and I usually add less than one qt per 10 hours. Try not to idle for long periods of time.
 
Mike5250 said:
With our 150 (0-200) we ran wide open throttle 2500-2600rpm cruise the first 10 hours. Phillips 20-50 is recommended by a lot of builders. About 100 hours on engine and I usually add less than one qt per 10 hours. Try not to idle for long periods of time.
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You probably wasted a 1000 hours of useful life of your engine. The reason you are using 1 qt in 10 is because you over heated the oil control rings and they no longer have the tension they need.
After the test cell run, I install the engine, run it for leak check, look it over really well, cowl it up and tell the owner to fly their engine as they normally would. They never use a qt between 25 hour oil changes.

It's your money, you can waste it as you please
 
i thought mr milot retired . i worked with him and parker ,and jay
 
Tom-D said:
You probably wasted a 1000 hours of useful life of your engine. The reason you are using 1 qt in 10 is because you over heated the oil control rings and they no longer have the tension they need.
After the test cell run, I install the engine, run it for leak check, look it over really well, cowl it up and tell the owner to fly their engine as they normally would. They never use a qt between 25 hour oil changes.

It's your money, you can waste it as you please
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Less than a qt every 10 hours and I ruined the engine? If you read the comment above I pretty much followed exactly what you recommended to others. I get a few drops out of the breather vent which is probably equal to the small amount of oil added between changes.
 
Watch the Phillips 20W50. There are two types of it: The 20W50 X/C and the 20W50 Type M. The X/C is the ashless dispersant oil for normal use, and the Type M is an ashless non-dispersant for those who want a straight mineral oil for break-in or whatever.
 
Dan Thomas said:
Watch the Phillips 20W50. There are two types of it: The 20W50 X/C and the 20W50 Type M. The X/C is the ashless dispersant oil for normal use, and the Type M is an ashless non-dispersant for those who want a straight mineral oil for break-in or whatever.
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ECI and many of us do not require"M". 20W50XC is not considered to be an EP oil in their " Oil talk for Dummies" Extreme Pressure oils have antiskuff additives that we don't want in the engine during break in, Only Lycoming requires that a few of their engine must have it, such as the 0-320-H2AD.
 
Run it hard. O-235s have a tendency to run too cold because they make so little power.
 
Ted DuPuis said:
Run it hard. O-235s have a tendency to run too cold because they make so little power.
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Only when they have the old Lycoming cylinders on it, they must be worn out prior to preforming as they should.
 
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