Bottom End Knock.

[zachmckinney98]

200k miles on engine. Truck ran low on oil had slight knock. Topped off oil, knock went away.
2 weeks later engine started knocking bad, oil level was good.
Knock is louder from the bottom of the engine and knocks about half of engine rpm. Slow but hard deep knock
I get the engine taken apart, top end everything looks good but one lifter has a loose roller. Figured that's what my hemi tick was.
Get to the bottom end take out all rod bearings and they all look fine. Couldn't find play in any of the rods as well before taking apart. Crankshaft seems solid. No scoring on crank.

What could the knocking have been?
I want to make sure it's fixed before putting all back together.

 

[AEDELGOD]

If rods and bearings look good, and the top end looks good, the only thing I can think of is a piston ring or wrist pin coming loose. Those would usually show obvious scoring in the cylinder walls. How do your cam bearings look?

 

[zachmckinney98]

Cylinder walls look good. Haven't looked at my cam bearings yet but the cam it self looked good.
Spark plugs were a little past due, maybe spark plug bad? I've read alot about possibly that but the noise seemed pretty hard hitting to be that.
Also had a exhaust leak before the knocking. But again, I don't know if either of those sound that loud.

 

[zachmckinney98]

Also , oil pressure never dropped. Stayed the same as before any knocking started. Around 50 psi running mid 30s at idle. Not fluctuating either.