Breaking in Continental O-200A -- done right?

For those of us who are moderately inclined to read the engine manufacturer’s instructions:

Lycoming Reciprocating Engine Break­In and Oil Consumption

Lubrications Oil Recommendations

PART II – OIL RECOMMENDATIONS FOR ENGINE OPERATION AND BREAK-IN
A. All turbocharged engines must be broken-in and operated with ashless dispersant oil only.
B. O-320-H; O/LO-360-E series engines may be operated using either straight mineral oil or ashless oil. However, if the engine is delivered with ashless dispersant oil, it must remain on ashless dispersant oil. The Textron Lycoming oil additive P/N LW-16702 must be added to the O-320-H and O/LO-360-E engines at airframe installation, and every 50 hours thereafter or at every oil change. This lubrication recommendation supersedes the lubrication recommendations in Service Instruction No. 1392.
NOTE
If it is determined that a FAA approved lubricating oil being used contains, in the proper amount, an oil additive equivalent to LW-16702, the provisions of this Service Instruction are met.
C. In all IGSO-480 and IGSO-540 series engines equipped with Simmonds fuel injection systems, it is al- lowable to use SAE50 or SAE60 grade lubricant providing the engine oil pressure does not exceed the limits set forth in the Operator’s Manual.
D. All other engines must be operated on mineral oil during the first 50 hours of operation, or until oil consumption has stabilized. LW-16702 additive may be used. If an ashless dispersant oil is used in a new engine, or a newly overhauled engine, high oil consumption might possibly be experienced. The additives in some of these ashless dispersant oils may retard the break-in of the piston rings and cylinder walls. This condition can be avoided by the use of mineral oil until normal oil consumption is obtained, then change to the ashless dispersant oil. Mineral oil must also be used following the replacement of one or more cylinders or until the oil consumption has stabilized.

That (fuel capacity) would be an airframe issue, not one the engine manufacturer is concerned with

It is very strange that the airworthiness limits are set so high. For a 540 (almost 2x bigger) it is something like almost 2x higher i.e. about 1qt/hr. This is atrocious and would indicate something severely wrong with the pistons/rings. It doesn’t indicate wear elsewhere because all the oil pressure-fed to the bearings gets recycled, so a worn engine just runs with a lower oil pressure.

However I did manage to achieve such a high consumption, by bunging up the piston rings. This was solved with an unapproved method involving Mobil 1 0W20 for 5hrs before a service (I never wrote this). That engine was later dismantled (I did an engine exchange) and overhauled and was found to be pretty perfect.

I don’t know what mechanism Lyco had in mind for the very high oil usage but if it was anything else to the above then it must be something fairly serious.

alioth wrote:

Looking at that Lycoming document, it has a formula for the maximum allowable oil consumption of an engine – it turns out that Lycoming only consider an O-320 to be consuming excessive oil when it reaches 1 quart every 2 hours (which seems awfully high to me!)

I guess that the limit is set only to make sure that the engine does not run out of oil before it runs out of fuel!

Looking at that Lycoming document, it has a formula for the maximum allowable oil consumption of an engine – it turns out that Lycoming only consider an O-320 to be consuming excessive oil when it reaches 1 quart every 2 hours (which seems awfully high to me!)

This would not surprise me, Jacko, and (whether it is correct or not) it illustrates a frequently overlooked component of the true cost of engine work: the large amount of avgas which needs to be burnt afterwards to get the cylinder(s) to bed down properly. It is probably into four digits. Often, flights have to be done whether you want to fly or not.

I recently heard of similar advice from a Swiss engine shop but using straight mineral oil for 60 hours after top overhaul is unnecessary, contrary to the engine manufacturers’ instructions, and potentially harmful. Straight oil provides limited corrosion protection and many private owners will take weeks or even months to fly those 60 hours.

As soon as oil consumption stabilises, usually within 10 hours, I dump the mineral oil and get some good quality oil with a full additive package into the sump to see my engine through the winter.

Not « babying », but also not overheating, the engine in the cruise is the key. Note, for instance, that turbocharged engines are run in with ashless dispersant oil from the start.

Zorg wrote:

I didn’t get any instructions by the engine or repair shop

A shop overhauled my O-200 in 2015 ; I still have the break-in instructions that I can send you via email (mine is on my profile).
Very simple :
- run the engine at 75% minimum (not letting you climb too high)
- check pressure ratio after one hour
- oil change after 10 hours
- oil change after another 25 hours
- oil change after another 25 hours
Which brings you to 60 hours with mineral oil ; normal oil and use after that.

Michel, Grenoble

But I do hope Jacko and others are right and break-in will be successful, and I finally get to enjoy my airplane.

From what you have said i reckon it should be. Then again, an O200 is not a critical engine. Don’t baby the engine, let it run flat out until the first oil change and you will be fine.