Maintenance & Avionics - Breaking in Continental O-200A - (2024)

Zorg

01

I finally got the top overhaul (1) of my Continental O-200A done (new cylinders, pistons, valves, …) and am now breaking in the engine.

I did two test flights of 1 hour each. I didn’t get any instructions by the engine or repair shop, and unfortunately I don’t have the operator’s or maintenance manual for the O-200.

Did I do this right?

• Using mineral oil
• Prolonged cruise flight at 2500-2600 rpm; with some leaning even below 3000 ft altitude
• Some leaning on ground
• Short descend and taxiing
• Let run for a minute to cool down before shutting down

Also, unfortunately, I leaned a little on take-off and the brief climb (2-3 minutes) — that shouldn’t be a problem for the break-in, right?

Thanks,

Michael

(1) See this thread for background info.

Last Edited by Zorg at 04 Nov 15:16

Zorg

Maoraigh

02

Maoraigh

Peter

03

The current Lyco break-in instructions are here.

These should be followed, because if you glaze a cylinder (even just one) you will be looking at a high oil consumption for perhaps well past 100hrs; in some reported cases indefinitely until the cylinders are removed and re-honed. Here is a thread on a possible solution to glazing, but it is really for the brave

Peter

Zorg

04

And how important are the first 1-2 hours vs. the following 10-15 hours for the break-in?

In hindsight, I probably didn’t follow the instructions perfectly during these first two flight hours (climbed pretty steeply for about 5-10 minutes with some leaning / used 2500-2550 rpm in cruise, which might be a little too low / needed to taxi 10 minutes longer than ideal for get fuel).

Could this already affect break-in?

Zorg

Peter

05

It is critical that the first 1-2hrs are flown at a high power, as specified.

If you fly it at say 50-60% then you will glaze cylinders. Don’t ask me how I know For a non-turbo engine, it means no Eurocontrol IFR flights because FL080+ means too-low power.

Peter

terbang

06

terbang

Zorg

07

Zorg

Mooney_Driver

08

Mooney_Driver

Zorg

09

Honestly I don’t know whether it was that good.

In the first operating hour:

• The mechanic told me that he did a short (15 minute or so) test flight after finishing his work.
• Then we did another flight for 20 minutes together, but we spent probably 10 minutes testing / taxiing.
• Then I did another 10-minute flight.

So in the first operating hour, about half an hour was probably spent taxiing or in low-rpm descent. :(

Sorry if I sound like I’m going a bit crazy on these datails, but I’m honestly quite traumatized from all the trouble I had with this airplane since the day I bought it. (And I spent about the purchase price just in fixing it up.)

I would hate to have a failed break-in out of ignorance / lack of instructions / stupidity.

I’m also very surprised that the first 1-2 hours are crucial for the break-in. Why is that the case? I thought it was a 25-50 hour process …

Last Edited by Zorg at 05 Nov 16:00

Zorg

Airborne_Again

10

Zorg wrote:

I’m also very surprised that the first 1-2 hours are crucial for the break-in. Why is that the case? I thought it was a 25-50 hour process

As far as I understand the first few hours are the really critical ones. My club did the break-in of two Lycoming engines this year. Lycoming’s Service Instructions call for high and alternating power settings the first 2-3 hours, including 30 minutes at full throttle. After that, the engine should be run at 65-75% power “until oil consumption has stabilised”. There is no mention of 25 or 50 hours, but it is not so easy to determine exactly when “oil consumption has stabilised”. I guess the recommendation of operating at 65-75% for 25 or even 50 hours is to make absolutely certain that oil consumption has become stable. On the advise of the CAMO, we ended the break-in period on one of the engines after about 30 hours with no ill effect.

Airborne_Again