Blowby video. How bad?
 

video >

http://i614.photobucket.com/albums/t...h_MVI_0791.jpg

I think the real test is to take the oil fill cap off and turn it upside down on the fill tube.If it just rattles off that is normal.If it is blown off by internal blow by then that is bad.

watch the video all the way through

Looks like a bit more than what I see on mine but it didn't blow the cap off. If its really cold out there maybe some of that is steam? Its the velocity of what I see that im sure about. Mine doesn't push out so fast.

nah its like 50 degrees today

youtube link

YouTube - 2002 for f250 7.3 new motor blowby

Is that a new engine? How many miles/hours so far? Sounds nice If it's a recent rebuild, then the blowby seems about normal to me.
Just my $0.02...

its a full rebuild new pistons rings rods etc. about 10k miles.

That is about what mine puts out and also does not blow off the cap. However, my motor also does not have the best compression either at 315 to 350 PSI

Hmm, 10k miles? In that case I think the blowby is excessive. Has it been like that for the entire 10k miles? Have you had the CCV mod since the rebuild or did you just recently run it to that spot behind the cab? I am wondering if maybe the hose froze up recently and the engine didn't have anyplace to vent the crankcase pressure. :confused:

i had the ccv mod/tube done with the motor so its pretty much had the same amount of blowby from the ccv and oilcap since i got it back 10k miles ago.. im wondering if the rings never seated

Question for yall....

with the CCV mod is the fill cap test still valid? wouldn't the vent give an escape route for the excess pressure and keep the cap from blowing off?

Me too, could be an issue with the rings.

You said "got it back 10k miles ago"...so I assume that means you had someone rebuild it for you? If it smoked like that since day one then I would take it back and see if they'll correct their work. I would expect some blowby on a fresh rebuild but it should clear up pretty quick...maybe 500 miles at the most.

Plug the CCV hose, put the oil cap on upside down and start the engine. If it blow right off then something isn't right.

EDIT: To clarify...if you plug the CCV and start the engine with the oil cap upside down it might topple off and that wouldn't necessarily prove anything. But if the cap shoots off like a projectile, then you probably have an issue. (sorry for the confusing post...)

Why plug the CCV? In stock form there is no restriction going into the intake. My opinion is the blow by is bad, but not critical.

pluged the ccv tube and did the oil cap test.. its not much worse cap still stays on but you can see the pressure is lifting it alittle more