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valve adjustment F or T mark???

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The "F" mark is TDC so is the best to use but the "F" mark is ok, just a little before TDC. I use the "T" mark with the cam lobes down or both rockers loose to make sure the engine is at TDC firing rather than at TDC Overlap. Some check for air pressure from the plug hole to verify the engine is on the compression stroke when approaching the "T" mark.

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Yeah cause ive been using the F mark then i tried the T mark after doing my rebuild yesterday and i couldnt get it right with the flywheel on the T mark. So ill probably just stick with the F mark. The F mark is ok to adjust valves on right?

Thanks

Greg

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Valve adjustments are made at top dead center (the T mark) of the compression stroke.

Four cycle engines hit top dead center twice during their four cycles . . . once on the compression stroke and again on the exhaust stroke. If the T is showing in the sight glass, it is at top dead center but it could be on either the comperssion stroke or the exhaust stroke.

I always take my valve caps off and watch the intake valve as I slowly turn the crank. When I see the intake valve open and close, I know that the next T is see in the window is top dead center on the compression stroke.

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Valve adjustments are made at top dead center (the T mark) of the compression stroke.

Actually T +/- 90 degrees of crank rotation is all the same for valve setting.

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Thumpinoke is correct the "T" is top dead center and the reference point for valve adjustment. The "F" mark is used to set the timing with a timing light and is the factory setting for a stock engine.

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