Exasperating --to be sure
Was the engine/prop/fuel,flown and tested as a unit before the contest?
I presume fuel used at contest was same mix/type oil?
I have never seen inside a BME110 but have seen /repaired overheated/siezed/ melted engines .
Only one thing will do it
too much heat .
too much heat can be caused by
too little oil
too lean a mix
too heavy a prop load
poor airflow.
It is strange these did not show up in precontest flight tests
At a recent contest -we had a friend get a deadstick on a flight - transition had gone bad-
the obvious points were covered and we then suggested that he drop the prop size to lessen load on the engine --to reduce heat (it was a hot day).
That fixed it
The hot day and big prop load simply combined to cause a condition not previously seen.

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