We found the source of the noise. The timing belt idler pulley failed. We found ball bearings and other pieces all over inside the lower timing belt cover. I am suprised that it made it the last 10 freeway miles that I drove after the noise started.
Here is a close up of the timing belt tensioner that is just a spring tensioner.
Pistons 1 & 3 had the most oil on them. Nothing majorly messed up.
Here is the Cylinder Head (8-valve SOHC with jet valves)
Huge intake valves & jet valve right next to the spark plug.
Oil pump pickup & crankshaft (engine is rotated upside down)
The only major wear found internally was bearing wear on the #4 connecting rod bearings. Everything else was normal.
You can still see the hatch marks in the cylinders after 80,000 miles.
Stock, oily pistons and rods. You can see the stock rods are very strong for a 114 horsepower engine.
