---------------------------------------------------------- Engines-List Digest Archive --- Total Messages Posted Sat 11/22/03: 4 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 06:29 AM - Engine break-in question (Dave Ford) 2. 06:54 AM - Re: Engine break-in question (Edward Chmielewski) 3. 09:06 AM - Re: Engine break-in question (Tedd McHenry) 4. 01:46 PM - Re: Engine break-in question (Archie) ________________________________ Message 1 _____________________________________ Time: 06:29:35 AM PST US From: "Dave Ford" Subject: Engines-List: Engine break-in question --> Engines-List message posted by: "Dave Ford" I have read some recent posts regarding starting a new or rebuilt engine and have some questions. I had picked up a package while at Oshkosh from Lycoming regarding some of their service instructions. One of them outlines the procedure they recommend for breaking in a new or overhauled engine. Their comments about breaking in the rings ranging from a cylinder that has new rings only or a completely overhauled engine, are that the procedure is the same. I don't have the instructions with me at the moment, they are at the airport but basically goes like this: Start engine to verify oil pressure and if no oil pressure shut down before 30 seconds. If oil pressure is fine run engine at 1000 rpm until oil temp comes to 140 degrees. After reaching 140 degrees run engine at 1200 rpm for 15 minutes monitoring cylinder temps and making sure they do not exceed limits. Shut off, let engine cool while checking for oil leaks. After engine cools moderately restart and bring oil temp back to 140 then bring to full airframe rpm for not longer than 10 seconds. Fly at full throttle for 2 hours then alternating at 75 and 60 % power until oil consumption stabilizes. This is the basic outline for the engine preliminary startup according to Lycoming, (it is from memory so may not be exact) before flying which contradicts the theory I've also heard from others of minimal engine start for no more than 30 seconds for checking oil leaks, then take off and fly full throttle for at least 1 hour. My question lies between the first 30 seconds and the runup procedures of basically warming the engine and oil, a short duration full rpm runup, then full throttle flight. I have a completely overhauled engine I will be flying shortly so am concerned about cylinder glazing preventing a quality break-in but am also wondering why there is a contradiction between Lycoming and the " don't run the engine on the ground" theory? I want to make sure that my engine runs ok for at least the time I can get to altitude (for sure) but don't want to inhibit the break-in procedure. Anyone have any helpful information? Dave Ford RV6 getting close ________________________________ Message 2 _____________________________________ Time: 06:54:02 AM PST US From: "Edward Chmielewski" Subject: Re: Engines-List: Engine break-in question --> Engines-List message posted by: "Edward Chmielewski" Hi Dave, By all means warm the engine up prior to full-throttle operation, 15 minutes shouldn't harm anything. You'll be amazed at how hot the cylinders will be (to touch) during the first 3-5 hours, then they'll be quite warm but not so hot you can't touch for a second or two. Buy or borrow an infrared gun, I've seen them for the R/C cars as low as $35. Good to 1 percent. The rest of your post sounds right, the only thing I would warn against is leaning more than 50 deg. rich of peak. Had an owner here in Michigan who ran a pair of Continental 520's on a Cessna twin at peak, very little break-in, and glazed all 12. Compression in the 40's. TCM had the cylinders analyzed, stepped up to the plate and covered all but the shop labor to remove/remount. This guy then took the first flight and started leaning again, did not follow the break-in of 'high power for 1st 2 hours'. I expect the shop will be seeing him in the near future. BTW, I've got about 3,000 hours behind TCM 520's and Lyc. 540's. Ed ----- Original Message ----- From: "Dave Ford" Subject: Engines-List: Engine break-in question > --> Engines-List message posted by: "Dave Ford" > > I have read some recent posts regarding starting a new or rebuilt engine and have some questions. I had picked up a package while at Oshkosh from Lycoming regarding some of their service instructions. One of them outlines the procedure they recommend for breaking in a new or overhauled engine. Their comments about breaking in the rings ranging from a cylinder that has new rings only or a completely overhauled engine, are that the procedure is the same. I don't have the instructions with me at the moment, they are at the airport but basically goes like this: > > Start engine to verify oil pressure and if no oil pressure shut down before 30 seconds. > > If oil pressure is fine run engine at 1000 rpm until oil temp comes to 140 degrees. > > After reaching 140 degrees run engine at 1200 rpm for 15 minutes monitoring cylinder temps and making sure they do not exceed limits. > > Shut off, let engine cool while checking for oil leaks. After engine cools moderately restart and bring oil temp back to 140 then bring to full airframe rpm for not longer than 10 seconds. > > Fly at full throttle for 2 hours then alternating at 75 and 60 % power until oil consumption stabilizes. > > > This is the basic outline for the engine preliminary startup according to Lycoming, (it is from memory so may not be exact) before flying which contradicts the theory I've also heard from others of minimal engine start for no more than 30 seconds for checking oil leaks, then take off and fly full throttle for at least 1 hour. > > My question lies between the first 30 seconds and the runup procedures of basically warming the engine and oil, a short duration full rpm runup, then full throttle flight. I have a completely overhauled engine I will be flying shortly so am concerned about cylinder glazing preventing a quality break-in but am also wondering why there is a contradiction between Lycoming and the " don't run the engine on the ground" theory? I want to make sure that my engine runs ok for at least the time I can get to altitude (for sure) but don't want to inhibit the break-in procedure. Anyone have any helpful information? > > Dave Ford > RV6 getting close > > ________________________________ Message 3 _____________________________________ Time: 09:06:36 AM PST US From: Tedd McHenry Subject: Re: Engines-List: Engine break-in question --> Engines-List message posted by: Tedd McHenry > Start engine to verify oil pressure and if no oil pressure shut down before > 30 seconds. What I've always done is remove the spark plugs and crank until I get oil pressure. In an airplane you can probably get some pressure to register just by hand propping. Is there any reason that would be a bad idea with a Lycoming? Tedd McHenry Surrey, BC ________________________________ Message 4 _____________________________________ Time: 01:46:08 PM PST US From: "Archie" Subject: Re: Engines-List: Engine break-in question --> Engines-List message posted by: "Archie" I have a checklist to give to customers which highlighted contains: 1.Fill oil filter until element is saturated, then install. 2.Remove all plug wires, and lower spark plugs. 3.Make sure oil is installed, then spin engine until positive pressure is attained. 4. Continue spinning for at least one minute additional. 5. Install plugs & wires. 6.Start engine using normal procedure. 7. Do not allow engine to idle below 1500 rpm for the first 15minutes. (this is especially important with new, or refaced lifters and/or camshaft) The reasons for this procedure are obvious, and is utilized whether a stock or racing engine. On the racing engines, there is no break-in. They are ready to "kill" in about 5minutes running. Archie > > Start engine to verify oil pressure and if no oil pressure shut down before > > 30 seconds. > > What I've always done is remove the spark plugs and crank until I get oil > pressure. In an airplane you can probably get some pressure to register just > by hand propping. Is there any reason that would be a bad idea with a > Lycoming? > > Tedd McHenry > Surrey, BC