Oh well you already know the answer to that question... If you pull the head you should replace the gasket.
You would probably be fine if you reused the same gasket for a test and tune session to see if something you did inside there made a difference as far as the timing chain popping off but you risk losing some compression because the gasket is designed to squish down into the little imperfections on both sides the mating surface and once you move it from that exact spot it won't reform.
Can you tell anything from looking down the timing cover? I figured if one of the guides came ut of it's holder/ broke you'd be able to see that by peering down the length of the cylinder.
|