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Valve adjustment question again
Hi, I have already read most of the valve adjustment articles and Wayne's article as well. Can anyone please explain why you need to turn the engine 120 degrees to get to the next set of valves? I know it has something to do with a 4-stroke engine turns 2 revolutions of total 720 degrees to complete one firing cycle.
Thanks,
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10-08-2003, 09:37 AM
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You need to get to a point where both valves are fully closed. This occurs once for every two revolutions of the crankshaft; the crank spins at twice the speed of the cams.
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10-08-2003, 09:38 AM
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And if you want to stay on the "same side" of the engine....turn every 240 degrees....
---Wil Ferch
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10-08-2003, 12:21 PM
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And you turn 120 degrees because you have a 6 cylinder engine. If 720 degrees is one firing cylce for one cylinder, then divide by six and you find out when each one fires. If you want to do it by bank instead of firing order, then you can do what wil says and go 240 to skip the other bank and to the next cylinder on the one your working with.
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10-08-2003, 12:27 PM
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Does it matter if the TDC is at compression or exhaust stroke?
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10-08-2003, 01:07 PM
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TDC is supposed to be on power/comp stroke, this way both are closed. The other TDC is in between ex/in stroke and both valves will be open. So i believe your looking for compression stroke.
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10-08-2003, 01:16 PM
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"The other TDC is in between ex/in stroke and both valves will be open."
Question, at exhaust stroke TDC, valves will be open?
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10-08-2003, 02:15 PM
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Quote:
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10-08-2003, 03:50 PM
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 By looking at this picture, at the TDC of exhaust stroke, 360 degrees, when the valves overlaps, the valves are partially open.
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10-08-2003, 04:15 PM
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