CAT3406E white smoke/Un-burned fuel smell?

What could be the cause of the engine knock? I understand the injector cut can be warped and not properly seating but after I had it changed out the engine now has a knock out of the cylinder?

 

sounds like a metallic knock. As if something is caught between valve and piston or something? Hoping it's not. But note that it only does it under acceleration and not at idle. Took the valve cover off and had the blow -by pushing the cover up from the pressure. Made sure it wasn't the rockers or any valve train parts. It appears to be coming from the cylinder. Cut the engine upon hearing that. Engine doesn't hesitate to turn over and start back up and again not noisy while idling. Gonna get it moved to the shop to see what else it could be. Can't trouble shoot it at my place any further? Shop stated next check would be pressurize the cylinder and drop the pan to see if liner is jacked. Anyone else that can chime in

thanks!

 

Oil pressure is steady at around 80cold.

 

Was a scored liner. Along with a cracked cylinder head. "in frame" here we come. Liner one was bad and the rest had glazed over. It was only a matter of time. At least we got it while it was here in town and not in never never land! Thanks to all who replied to this post. Issue has been resolved to the tune of around 13k plus or minus!

 

Yeah I almost bought a kit for the after market but after all the re do or bad stories I heard I went with CAT parts not to say it couldn't happen but just felt a bit more piece of mind.