Lycoming engine break in

4RNB

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4RNB
New engine being installed on my C172. I do not have the break in instructions in hand so have been reading and watching youtube videos, Mike Busch and I think SI 1427C from Lycoming. Busch seems to suggest new Lycoming engines have steel cylinders and take maybe 5 hours to break in, maybe he mentioned to change oil within first 10 hours. Video did not specify, but I assumed then just go fly normally. Lycoming SI 1427 only talks about some brief periods on the ground and 2 hours in the air.

A friend hired out some CFIs to break in his engine, I thought he had them fly like 50 hours.

What does Lycoming and/or Busch and/or other subject matter experts say to do beyond the two hour flight in the SI 1427c? Is there some 40-50 break in?

Basically the AP installing the engine is going to do the 2 hour flight, then hand off to me. What should I expect?

Thank you.
 
It's not a sugar wafer Conti. Run it at 75% for a couple hours, don't baby it for the rest of its life, and you're G2G.
 
@4RNB Follow the engine builder's instruction to the letter as your warranty will likely depend on it. Use the oil they recommend and break-in procedure. The first 2 hours steel cylinders will initially break-in. Most instructions want you to run full power to facilitate ring seating in the fresh cylinders. CHT's will drop rapidly once ring seating occurs.
 
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In a 172 there isn't much to do, its not constant speed, or turbo charged.
Avoid prolonged idling, firewall it, and go enjoy.
 
In a 172 there isn't much to do, its not constant speed, or turbo charged.
Avoid prolonged idling, firewall it, and go enjoy.
Yes firewall it!
I broke in a lycoming 320 couple years ago my self. I installed the motor with my IA mechanic. Followed the instructions from lycoming . After 2 sessions on the ground, I flew it at 75% power for 2 hours and then the last 30 minutes wide open throttle. Burned a qt of oil in 2.5 hrs.
Second flight was 65-75 power for 2 hours and then wide open throttle for 30 more minutes. Burned maybe a half quart of oil in 2.5 hours. Then the third flight was 2 more hours and it did not burn any oil. I was amazed. From then on it stopped burning oil for the most part. It was broke in at about 7 hours.

I just flew it to 400 hrs this past weekend, it burns a qt of oil every 14 or so hours and has run flawless so far. Installed it July 2020, coming up on 2 years now.
 
Lycoming service instruction 1427, "Lycoming Reciprocating Engine Break-In and Oil Consumption," is available from Lycoming here. It's pretty much as @Gary Ward described. 1427 is not just "some brief periods on the ground and 2 hours in the air," it says to run the engine at 65-75% power until oil consumption stabilizes. In my case that was pretty noticeable and took a bit more than 2 hours, probably somewhere between 5 to 10. I'm about to start the process again, we'll see how that one goes. When Mike Busch warrantees my engine I'll do what Mike Busch suggests, in the meantime I'm going with Lycoming.

Nauga,
high, hot, and overshot
 
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