With exhaust valves, the clearance can become tighter over time as the valves or valve seats wear down ... lobes or rocker arms using thin feeler gauges as pictured above. (The camshaft must ...

it's the cut of the valve face and its corresponding seat on the cylinder head that determine how well it'll seal and how well air will ultimately flow past it. You see, a valve spends most of its ...

A compression test reveals the condition of your engine's valves, its valve seats, and piston rings and ... STEP 2 Start the threaded end of the compression gauge in a spark plug hole by hand.