Wednesday, May 13, 2020

3 hours at 160+

MPH.

No, seriously.

Airspeed, and the groundspeed was pretty close to that, average.

See, I got 6 cylinders on my 182 redone. And the conventional wisdom is that they need to be run hard for "Break-In"...

For 10 hours. at 75% power.

75% at 5500 feet works out to be 142 knots. a knot is 1.15 statute miles per hour. You can do the math.

Now, I am not sure why the "Break-In" time is a magical 10 hours....It would seem to me that after an hour or so the rings and cylinders would be worn together...I mean, I have rebuilt hundreds of other types of air cooled engines and they are considered "Broken-In" after 30-45 minutes....the rings and the cylinders have worn together and at that point oil consumption goes to whatever is "normal". I mean, I am talking from 5 hp mower engines to high compression multi cylinder air cooled diesels. All had the same break-in characteristics and roughly the same timing. the general wisdom was an hour under a half or better load to seat the rings and wear the cylinder finish to properly hold the oil for compression.

But I don't get a warranty unless I do (and log) the break in time as per recommendations. So I am doing the break in per the specs.

Today, 3:19 ....450 miles more or less. One landing. About half flown by hand, the rest I let the autopilot ("George") fly. Got the engine nice and warm burnt a lot of fuel.

I gotta say that central Indiana and Illinois are still having lots of traffic on the roads.  Aaron says that his area is way down in traffic, but I did not see that on the roads over which I flew. Larger state highways, Interstates, US highways...all fairly normal. Even Indianapolis roads were not terribly empty, at least not on the north side.





3 comments:

Old NFO said...

Have you changed the oil and filter yet? That's usually recommended after 3-5 hours at 75% to get rid of the iron filings. One of the reasons, from what I remember, is that it takes roughly 10 hours to get the sleeves 'smooth' so that you don't get peaks/valleys that will gum up. Also, I 'think' you were supposed to keep oil temp below 240 degrees initially. YMMV, and that was years ago.

B said...

Nope, they wanna do that at 10 hours.

And yes I am keeping the oil temp at the specified limits.

Old NFO said...

Interesting...