I have checked in your save, the rocker shaft was completely destroyed (can be noticed by missing springs). And btw, your distributor and fanbelt tightness are badly alligned. I'll allign them for you. You'll also need to replace the starter and water pump soon.
Tips for tuning:
-When your engine is chirping/ringing, that means the spark timing is too advanced. Loose the screw and scroll up until it stops. You should get max. power and fuel economy.
-For fanbelt tightness, keep it 2 ticks from fully tight (1 tick = 0.5 of tightness)
Here's the save. I fixed the spark timing, fanbelt tightness and gave rockershaft 20 percent of condition.
