We all know what our engine's blow-by looks like when it's warm/up to temp... minature vapor cloud/stream depending on the severity...How about when my son was cranking for about 10 seconds and I was bleeding off the HP lines? Just clear air.Same when allowed to start the other day.... about a minutes worth... just clean clear air. I had to check twice with my thumb to confirm there was air movement.... I could stop the air easy coming out the pipe, and in about 5 seconds, I could finally feel a little pressure under my thumb. There was a slight 'poof' when I let go but no steam or vapor.Safe to assume this is vacuum pump gone amuck? Most of my ag diesels will instantly have some variance of smoke, vapor, or bunny fuzz right at start-up.Got a Goulds' kit on the way.. I'll need to check the downstream lines too.I got my intake valve leak isolated... #1. I have a pretty good idea this was already on the way out, and opening up the intake system to do the IP allowed me to hear it! I gotta get some hay hauled asap, and I guess I am going to take a chance and run it as is until the truck can sit for a couple days.This could be a gamble, I am aware that if it is a foreign body, then there could be a large string of crap to R+R. But, if it's just a blob of carbon that needs a '3000 rpm tune up'... Either way, I'll know soon!

Vacuum pump blow by is typically created by a vacuum leak in one of the hoses. Broken or cracked piece of plastic tube, harden rubber connectors, etc.I would look at the simple stuff first before yanking put the vacuum pump and power steering box combo to rebuild that vacuum pump. Unless you have a oil leak there too. All diesel engines will have a certain amount of blow by but my rule of thumb is as long as the blow by isn't serve enough to blow oil out the breather tube your fine.

That's what I needed to know! (where the source of vacuum leak typically is) The oil leaks all over this thing made me start this whole process of 'search and rescue' any and all leaks.which originally started as a vp replacement, then steering gear r +r, front main seal, 'the right stuff' on the front cover, set the valves, new idler, belt, new ac condensor, fixed the broke peg on bottom of exchanger, hammered out the deer imprint in the front bumper.what still needs doing is replace ball joints, pull head and fix whatever need fixing there.

Oil Leaks locations

[*]Front crank seal

[*]Rear Crank seal

[*]Tappet cover gasket (or AKA cam cover gasket)

[*]Vacuum pump

[*]Valve cover gasket (rare)

[*]Turbo drain (hose connection)

Vacuum leaks

As for vacuum lines for the plastic just remove them and flex the line in a big arc and if the line is crack it will continue to crack or break when you bow the plastic because it just plan brittle from age. I just grab some vinyl tubing and replaced all the lines on MoparMom's 96 Dodge for the same issue. Other than that the vacuum pump becomes a air compressor and imitates blow by issues.

Personal note: I need to catch you phone call I'll be home tonight!