I have a 2004 Ford expedition 4.6 triton. the wife drove it to work and it would not start when she went to leave. While cranking it over I noticed it sounded like no compression. The timing chain rails went out so I am replacing the timing chains. I removed the valve covers and on the Driver side I found every one of the rocker arms laying in the head. I have read that the lifters may have collapsed and let them fall out. I also noticed that all 8 of the rocker arms are cracked. Can someone advise me on if I can replace the lifters and rocker arms and what's the chance I lost valves in this head.

 

How many miles on it?

 

You are going to have to borescope it and possibly pull the head. You may have piston damage.