Millenium Cylinder Break-in

[Rick_Champagne]

Scenario:
5 new Milleniums on my C-145-2.
(I had already done one a few yrs before)
Added EI 6 channel CHT monitor
Added Aeroshell 80 mineral
Primed through oil pressure line port
Motored with no ign or fuel.
So ,
I'd like to motor it more to see oil Pressure and pump lifters before actually starting it.
How about I turn the sump heater on and then give it more motoring? I am also in a heated hangar
Would that hurt anything as related to break in of the cylinders/ rings?
Considering the avg. OAT is 30-40 deg f, should I wait til above 50 OAT so that i can get and keep a good oil temp at or above 180 quickly, as to not prevent possible glazing? Located in Virginia
Any comments welcome!

[n2582d]

I recently replaced a Millenium cylinder on a friend’s 172. Followed these instructions:

Cylinder Replacement Instructions .pdf

(851.28 KiB) Downloaded 35 times

[Rick_Champagne]

Thanks Gary. I've used the Phillips Type M 20W50 on the last cylinder break in I did in the summer. Worked well. This time I went with the Aeroshell straight weight 80, (or 40W) like on some other Continental engines I have done. I do have the Superior document , and it's nice to see some of the other details Johnston uses. Considering just the oils, I believe they are both good .I just need to be sure with the OAT I can get the temp up quickly .

Rick

[n2582d]

Rick,
Here in California, if it’s below 60°F it’s too cold to go outside, much less flying! Here the concern has always been overtemping the cylinders — never gave a second thought to temps being too low. Section 7-2.4.1 “Engine Break-In” of the Continental Standard Practices Maintenance Manual warns in bold letters, Do not permit cylinder head temperature to drop below 300°F.” and, further down, “Carefully monitor engine instrumentation to maintain levels above the minimum specified cylinder head temperature and oil temperature.” In Bent Props and Blow Pots: A Pioneer Remembers Northern Bush Flying, Rex Terpening writes of draining the oil every night and then heating it up before pouring it back in the engine in the morning. Would that be an option for you during break in?

[Rick_Champagne]

Gary,
Interesting info on the low side. If I turn on the sump heater in the enclosed hangar, the oil temp would be good to start but hard to maintain after its running and even get above 100 f for takeoff with a short ground run, if the OAT is less than 50 or so. Its just a break in in concern. I blocked the cowling sump opening and cooling tubes. Superior said I should wait till avg oat is close to 50 , and then start it, check it ,and get airborne. I will still run the heater , and motor it a bit more with no ign or fuel to see if I can show oil press. and fill the lifters. I'm on a 3200' grass strip ,and VA does not usually see these low avg temps and the snow that has come and somewhat gone. I think some patience might be in order ... When it's right , then there can be flight.

[Bruce Fenstermacher]

Rick, at work we start a lot of new or overhauled engines, mostly i0-550. We follow Continental procedure which calls for pumping oil in the oil galley on one side of the engine till oil is seen at the pushrod tube at the other end of the oil galley on the other side of the engine. In most Continentals made in the last 40 years the place to pump is the oil pressure port on the aft left hand galley so we take the valve cover of the #1 cyl and wait to see oil. The oil pressure port on a C-145/0-300 in at the aft right hand side so I would take the valve cover of the #2 cylinder lookin for oil. If you want to be overly cautious you could remove all the valve covers and observe all the push rods. I takes about a qt oil oil to fill the galleys and see oil at the other side. If I pumped a quart of oil in the engine and did not see oil on the other side I would hand rotate the engine about 3 rotations to move the hydrallic units to another position and look for oil, which you are likely to see quickly after rotating the prop.

We NEVER crank the engine by the starter to see confirm pressure. The first time we crank the engine with the starter the ignition and gas are on and we intend to start the engine. In the last 5 years we had probably started nearly 20 engines and have never had any issues.

We use a regular qt size hand pump oil can to prime engines. Yes it is a lot of pumping and your hand gets a cramp. Twice I've uses a home brew pressure pot made from a gallon size plastic organe juice container. with about 20 lb of air pressure. The orange juice was specifically bought for it's container.

[cessna170bdriver]

The 50F OAT for break-in sounds about right if the goal is keep oil temperature above 180F. Without the oil and cooling block-off plates my engine runs 130 degrees above OAT. With all three plates installed it runs about 150 degrees above OAT.

[GAHorn]

I’ll question… What is the difference in “motoring” the engine until oil pressure is confirmed…. versus Starting and Running the engine until oil pressure is confirmed…? (and I’ll answer my own question….motoring it harms and possibly overheats the starter motor….. and starting the engine is the method which provides faster oil pressure. doh)

Yes, …Certainly… Pre-Lube the galleries…. But the engine SHOULD have been ASSEMBLED with all critical parts already lubricated during assembly…. therefore No Need to worry about this insignificant factor. IMO.