Quality - What's that? You (customer) are the test lab.
BTW that probably has a sight glass on top unseen in your picture.
You read it like this look for better in color or videos as needed if unsure.
Crude basics like this,

This is read while operating at a raised idle,
BTW that probably has a sight glass on top unseen in your picture.
You read it like this look for better in color or videos as needed if unsure.
Crude basics like this,
This is read while operating at a raised idle,
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