"Patrick Johnson" wrote in message
ink.net...

It sounds like
someone is tapping on the block with a small hammer. Could this be the
rod
cap issue coming back to haunt me?

Could be.

The more the engine runs, the less
frequent the knock occurs. Could this be lifters?


Could be that too. It is possible that you aren't getting enough oil
pressure to one of the lifters, or that the lifter is bad. It is common for
a worn lifter to collapse when the engine is not running, and then take a
while before the oil pressure expands it back out. During this time you get
a very load "clack" from the valve train (higher on the engine) then
diminishes and finally goes away after a few seconds of operation

A rod knock, on the other hand, originates lower in the engine, is a more
solid knock, and doesn't go away.

The first thing I would do is remove the valve cover and visually inspect
the rocker arms. Rotate the engine slowly by hand and watch the operation
of each valve. If one looks different then focus on that.

If you can remove the rocker arms one cylinder at a time you might want to
remove one cylinders at time and see if it makes the knock go away. It
shouldn't effect a rod knock, so if you make the sound go away you have
found the culprit.

Rod