Oily soot on side of valve cover Cummins ISC
Ok, I've asked this question on the Cummins engine forum when I thought this might be an exhaust leak but I'd thought I'd throw it out to a wider audience here.
On a long trip last fall with a lot of uphill/downhill driving I started to notice some oily deposit on the side of the valve cover. It continued to increase in size and after six or seven days covered the entire side of the valve cover.
I just got it back from a very reputable diesel shop and they said they have thoroughly checked the exhaust gasket and manifold and they are fine (though they did catch my lift pump leaking). A second mechanic checked it after I insisted and came to the same conclusion, it's not the exhaust.
If not the exhaust, what can be causing this? I'm thinking maybe some oil was coming out of the slobber tube and being thrown up? Slightly loose valve cover?
Any ideas?. Pictures below, in the second one I ran my finger down the cover just to determine the type of soot.
Retired Canadian Army WO (1972-2000)
2003 4005 DSDP 350 Cummins/Spartan chassis
Toad 2103 Ford Edge w/ Patriot Braking system/Blue Ox base plate/Ready Brake tow bar.