why is the inlet valve timed to close after BDC?
why is the exhaust valve timed to open before BDC?
2007-10-01 06:33:36 · 2 answers · asked by Anonymous in Cars & Transportation ➔ Maintenance & Repairs
http://en.wikipedia.org/wiki/Four-stroke_cycle
2007-10-01 06:41:06 · answer #1 · answered by Mr. KnowItAll 7 · 0⤊ 0⤋
The exhaust valve usually closes a fraction After TDC, and opens again BDC, because the inlet valve is set to open and close, between the actions of the exhaust valve, (or visa versa, if you prefer,) because of the rotation of the engine, as one closes, the orther opens in rotation, thus giving fuel to the engine, (and after ignition of the fuel between the head and pistons) the exhaust opens to dispurse the "spent" fuel, "carbon monoxide", "exhaust fumes". If the inlet and exhaust valves were'nt "timed", in this way, the engine wouldn't start, if by some chance it did, it would simply blow up under the combustion pressure being created, and the exhaust gasses, having nowhere to go except perhaps "through" the engine, any way it can. hope this helps.
2007-10-01 14:31:24 · answer #2 · answered by peter e 2 · 0⤊ 0⤋