At bottom-dead-center (BDC) the inlet valve is closed and the compression stroke (b) starts. Work is done on the air/fuel mixture ... represents this behavior for a Mitsubishi direct injection engine ...

Along with a TIG welder and mechanical ingenuity bordering on genius-level, all of which come to bear on this fridge compressor to four-stroke engine build. The video posted by [Let’s Learn ...

Why are there four? And what is a stroke, anyway? A modern gas engine ... This is commonly how modern combustion engines work. Some engines use fewer strokes per cycle. A two-stroke engine ...