Picture of timimg marks for the 3.1

The cam pulley should have three oval holes and one smaller circular one. That smaller one should line up with a dot on the crank pulley. At the same time the cam pin will be at 3 o'clock and the key way will be at 10:30/11 o'clock. Google is your friend for diagrams!

After tear down, was the timing chain and or components 'obviously' in need of replacement on this 3.1 GM engine? .. What were the symptoms that lead to this conclusion .. Just courious.