cummins isx 2009 international prostar premium

[Unilevers]

(06-10-2016 )seanmarl Wrote:  Hello,
while doing the soot cleanout of the intake/egr system etc. after pulling the manifold I was looking in the head with a flashlight and around I believe the #4 intake valve (about dead center of the intake port in the head) it is wet with what looks like oil. Is this most likely valve guides? or possibly a leaking injector? maybe when I get it back together I was thinking of doing the injector leak test as im thinking if the injector is leaking this is where it would be?
thanks and sorry if my logic doesn't follow, im pretty new to these engines.

honestly its most likely the valve stem seal. Pop the cover and look in the valve springs to see if you see the seals riding up near the top of the valves, they are supposed to be stuck to the top of the guides.