when did i join cessnamotoring?

just kidding, welcome to NAM!

 

Thanks! In my case is would be Cirrusmotoring! But who's counting. The Cirrus site like NAM has been a source of great learning. You can post a question there and within minutes have an inbox full of very qualified responses. I am finding NAM very useful though I am not sure I am getting full value as I haven't yet learned how to effectively search...but I will! Just for the record I did own a Cessna once and still fly one regularily.

 

The RPM's run and the engine layout will contribute to your experiences, but they can not and should not be used to compare break in procedures for an engine that rev's several times higher. And the stresses being applied with a low speed motor are very different than the ones on a car engine.

And yes.....welcome to NAM

 

The question that lingers in my mind is that the key in seating the rings would be to get the engine hot quickly and leave it there for at least an hour. I don't understand why that would differ with any engine. But I want to...I ready for my education and thank all guru's in advance!

 

I don't know of a single car manufacturer or engine builder that recommends that you cruise on the highway at a constant rpm to break in their engines. In fact, they all will say that you need to be varying the rpm's and try to make sure you are not reving the engine too high.

 

Perhaps, we should try strapping some wings on a MINI and taking it to 12K feet for an hour, then check the rings vs. ground level driving? OR, take the Cirrus (nice plane) down the highway at full throttle for an hour . . . Personally, I'd rather see the Cirrus on the highway!

I, too, am a pilot. We also need to consider the temp differences at altitude. Even though 12K feet isn't that high, there can still be a considerable temp difference. Try running your MINI is a refridgerator for an hour. Turbos wouldn't be very happy, but naked MINIs would have to work even harder to get to temperature.

 

Now that is a job I want...

 

Hondo, looking at that engine specs, it's a 9+ liter 6 cylinder. 5.25" bore x 4.25" stroke. That's a pretty undersquare engine meaning at 2700 rpm, the pistons are moving ~2300 ft/min. That's putting along pretty gingerly in the grand scheme of things (probably for reliability sake).

One of the professors at my university did quite a lot of engine building for Winston Cup, etc. They broke all the engines in on a dyno. After tuning or whatever else they were doing on the dyno, they'd tear the engine apart, re-ring it, and put it back on just long enough to break in the rings.

 

There are obvious differences. I flew to St Louis yesterday morning and wanted to be there by 7:30 am, good news: I made it at 7:30 with the help of a 40 knot tail wind (I was doing 223 kts across the ground). No real bad news, I did pay to leave the heater (engine) plugged in while I was gone until 3 PM and when I started the oil temp was already at 150 degrees with an outside air temp of 30. The heater allowed the engine to maintain the left over heat from the run over to STL, even with the oil cap off which I always do to release the condensation that builds up from cool down, reduces the opportunity for internal corrotion.
"A friend of mine" did an hour flight at wide open throttle (about 175 knots) only climbing to avoid power lines. A few cars were surprised as I understand it. Army helicopters will rountine fly NOE (nap of the earth) to avoid being a target for any longer than necessary. By the way the temp where I was cruising yesterday were -8 (C). Cylinder head temps didn't get much above 200 (F) during the flight, 'normal' is about 300 (F). Didn't make the trip the night before because of weather and I almost drove the Mini just for fun (6 hrs) but they were talking hail so no Mini trip.

 

Thanks, good info, I 'assumed' something like this but didn't know. Interesting.