99 FG. Am I correct in my observation that the 4d34 in my 99FG lacks a PCV system and is simply vented to atmosphere as if we still lived in 1963? All I'm seeing is a tube coming from the back left side of valve cover terminating beside the starter. I assume this means there was a loophole for medium duty trucks when it came to emission requirements? Even my old 70's Mercedes diesels vented the crankcase into the intake manifold somehow.
4d34 PCV system
- Thread starter kerry
- Start date
I have been getting some puffs of blue smoke at times so I removed the turbo intake hose to inspect and that is what made me think about the PCV system. I am used to seeing a fair amount of oily grime in there on my other diesels which feed crankcase fumes through the turbo. There was only a slight oily residue. I haven't looked closely at the PCV hose while running but looking in the vicinity of the hose, I'd say I have very little oil exiting the PCV pipe It would be easier to install a catch can if it didn't have that goofy aluminum hose. I guess I'm surprised that since Californians discovered venting the crankcase to atmosphere causes smog in the later 1950's that it's taken this long to require PCV systems on trucks, especially in California.