Graham Singleton wrote:
>> I have now about 2 hours on the engine, and it is starting to cool down
>> considerably. Can't tell of course whether this is due to some cooling
>> modifications I made, or because the engine is now a little less tight.
>>
> Frans
> Engine "break in" as they say in the US, should be done at relatively
> high power settings. 60% minimum.
> Running at low power can cause glazing of cylinders and the piston rings
> won't polish squarely unless they are properly loaded. My understanding
> is that if loading on the rings reverses they will wear barrel shaped
> and start pumping oil.
I agree, but the problem is: HOW?
My understanding is that one should not load the engine before the oil
gets at least 70 degrees Celcius. Before that time though, the water
boiled already. The vibrations were also not really inviting to try some
higher power settings.
Now the engine starts to run much cooler, and runs smoothly, I plan to
do a few sessions with higher power settings. For breaking in, of
course, but I also won't let anyone test-fly this thing before I have
some confidence that the engine will be able to complete its take-off
run without boiling. ;-)
--
Frans Veldman
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