Quote:
Originally Posted by bigdano711
...
...
When they're tight like that, it means the valves are not closing all the way?
|
Yup! Well, they have to be pretty tight to prevent them from closing all the way, but yup, that's it. The real problem is that the hot exhaust gas blowing past the valve seat will eventually damage the seats and valve.
Too loose, you get tappet noise but the valves definitely close. They may not open all the way to let the fuel/air in or the exhaust out efficiently. Performance issue for sure. It essentially changes timing of the combustion cycle.