Valve wear

[KooLaid]

So I've read about two reasons how valves fall out of adjustment. Well 2 common reasons/excuses.

1. valves stretch (causing too loose)

2. valves pounding on the valve seats cause the valves to eventually sink
into the head slightly. (causing too tight)

So which one is it? I think it's just valve stretch. But I might be wrong.

[Bryce]

it's actually the valves and seats wearing and making the valve sit higher in the head to go tight or to go loose is caused by camshaft wear it's extremely unlikely that the valves stretch at all unless the engine is overheated in which cas the head of the valve can become concove (or more concave) which usually results in the valve staying partially open at all times and causin a pretty massive compression loss

[Anonymous]

engine is overheated in which cas the head of the valve can become concove (or more concave) which usually results in the valve staying partially open at all times and causin a pretty massive compression loss

To expand on that, you will feel it as well, and this is a real good way to crack your valves as the hot gases will heat them up, however without full and uniform contact with the seat they cannot transfer the heat away; they basically bake themselves to failure. This'll result in a massive power loss, and probably some funny colored smoke out the back end - you'll see the cracks (or rather, chunks of the valve missing) when you pull the head thinking it's just a gasket.

[Bryce]

engine is overheated in which cas the head of the valve can become concove (or more concave) which usually results in the valve staying partially open at all times and causin a pretty massive compression loss

To expand on that, you will feel it as well, and this is a real good way to crack your valves as the hot gases will heat them up, however without full and uniform contact with the seat they cannot transfer the heat away; they basically bake themselves to failure. This'll result in a massive power loss, and probably some funny colored smoke out the back end - you'll see the cracks (or rather, chunks of the valve missing) when you pull the head thinking it's just a gasket.

that is if you let it go that far