Blow by

[6speedsd]

Here lately, on multiple forums, I've seen a lot of mention about excessive blow by out the oil fill tube. Random people have random problems with their truck and someone will mention to check how much blow by they have, stating I'd it's excessive, you have major problems. What's causing the excessive blow by? Heads that need a good working over? Worn rings? How much is technically considered excessive? Light puffs of steam? A steady flow?

 

[Daniel@RudysDiesel]

My 6.4 has a steady stream when its hot at idle

 

[AirFishAutomotive]

My 6.4 has a steady stream when its hot at idle

one of mine are like that as well and there are no compression issues or head issues as its been comp tested, and heads were redone in the summer

 

[6speedsd]

Was referring to 6.0 but I assume its basically the same principle regardless of engine.

Just curious what is considered excessive. My 6.0 has a steady stream when hot just like y'all mention with your 6.4's.

 

[ghohouston]

Its usually caused by worn rings, when it'd excessive. Some is normal. Most people say if the oil fill cap blows right off when flipped upside down on the fill tube, blowby is excessive, if it just rattles around, you're in good shape.

 

[ghohouston]

And on my 2002, I had at least 350 psi across all 8 cylinders, and had a good bit of blowby when warm.
https://www.youtube.com/watch?v=sN65PhwFt1k&feature=youtube_gdata_player

 

[ghohouston]

This was a 6.4 company truck, with too much blowby

https://www.youtube.com/watch?v=j8fUllbhAos&feature=youtube_gdata_player

 

[6speedsd]

Thanks man! That's what I was looking for.