I have recently developed a distinct random tapping noise from the engine it normally does it at running temp and is more noticeable at idle. Could this be a injector, cam follower? I hope its not a piston skirt. What's ur all take on this

It isnt good.  Rod bearing or injector is typical for a tap.  I dont recall seeing any lifter issues.  You might get a clue by sending an oil sample in and seeing whats high...  

Edited September 8, 20168 yr by CSM

The odd part is it don't do it all the time it's quite random

It's also not a hard knock type of noise it sounds like a hydro. Lifter that won't build up

These have solid tappets though....

I'd start with doing the valve lash. Maybe you've got one a bit loose that is slapping around?

But wouldn't the lash being off do it all the time, 

Might, might not. Thick oil in there could stop it while it's cold. Depending on how the bridge falls off the rocker or stays on it and lifts off the valves can make a difference. Just thinking of cheap things first 

True, I guess I need to start checking it over good 

I vote lash as well otherwise get a northern tool 5 dollar stethoscope to help isolate location block or head.....

Also I'd say change the oil but put cheese cloth over the pan to filter oil through it can get messy so plan accordingly once drained pull cloth and inspect with daylight followed by the brightest light you have access to...  you likely won't see anything but with the light if you have issues the cloth will likely glint or glare from shiny metal if you see that jar up some drain oil and send it out for analysis.... best of luck 

Edited September 11, 20168 yr by WiscoRedkneck

Steven,

 

You may want to double check for an exhaust leak.  The ISB just seems to love cracking an exhaust manifold and/or losing an exhaust stud near #6 cylinder.    Rattle Monster happens to have both at the moment, and over the weekend buddies had trucks over and of the other three in my driveway, 2 were missing exhaust studs. 

 

Hope it is something simple like that!

 

Hag

I'll check that some time but now I'm fighting the nv5600 issues again