I think the valves on my 89 350 are out of adjustment. They are so mal-adjusted, I can't get the thing started. How can I adjust my valves without the engine running? I tightened/lossened a few valves a got the engine running decently, it would backfire a bit and it stalled out when it was put in gear. I hear 2 loud, sharp pops...could I have bent a push rod? Does that explain why she won't run now?