Forgot to include the link mentioned in my last post.

http://www.peachparts.com/shopforum/diesel-discussion/368432-delivery-valve-o-ring-problem;-car-clacking-loud.html

Lots & lots of members give good advice. Diesel911 is one of the many. Search through his and other good guy's posts for info and then try to verify with a few others.

I make mistakes, but try to keep that to a minimum by lots of reading.