Blow By

[BigBearZach]

Ok so im pretty sure i have a good bit of blow by. I can tell because it is coming out of the dip stick, the oil filler neck and the tuna can. so why a i getting blow by so bad

 

[Big T]

If it's the '94, it's just due to age. How many miles on that thing? My son's '94 has blowby coming out the filler and the dipstick.

 

[BigBearZach]

It has 167xxx

 

[Big T]

It must have been overheated a couple times. They all have some amount of blowby at 167K, but pouring out of 3 orifices like you describe is a lot for 167K. Yours would not be the first '94 to have overheated. They can go a long way in this condition.

 

[tanman_2006]

Try a couple oil changes with auto rx. I'll post a video of my 95's blow by when I get home.

Sent from: Source Unknown

 

[BigBearZach]

now short of tearing apart the motor what can i do to fix it

 

[Big T]

Nothing can be done, except rebuild the engine or replace it.

 

[tanman_2006]

AUTO RX! It is an oil additive LOOK IT UP.

~220K on the engine 285K on the truck, I have ran amsoil w/ dual bypass since I got the truck @ 180K. Has buddy chip and gm4 with budget 3" exhaust.

[video]http://s597.beta.photobucket.com/user/tanman_2006/media/Green%20Beast/photobucket-18958-1360218252728_zps4dcb2382.mp4.html[/video]

 

[bison]

Pipe the CDR to the road,..it'll cut your oil burning by 90%.

 

[tanman_2006]

Mine is stock set up and I can go 10K w/o using hardly anything. Mine doesnt look like a steam engine either and if it did I might give a road draft tube a try.

W/ hx 35 and alot of flogging you will suck oil vapors faster, and if you added a stupid little cummins style filter then you arent flowing enough air.

 

[BigBearZach]

i was thinking about tieing my cdr in to the oil return line off of the turbo

 

[bison]

You can't do that.
You'll blow the seals and pop the dipstick right out.,...crankcase pressure(blowby) has to be released either by feeding back in the intake or to the atmosfeer.

 

[WarWagon]

Pipe the CDR to the road,..it'll cut your oil burning by 90%.

This much blow by is a bad idea to vent to the road! When you get off the freeway you will have so much blow by coming out of the tube your truck will look like it is on fire!

So ask yourself if you really NEED to fix it? I have only bothered on mine because the engine was leaking oil bad out the front seal from shot bearings. (And the other ate a foreign object requiring heads and pistons...)

AUTO RX etc. can free up stuck rings. Otherwise they are worn out, overheated and lost their tension, never broke in properly, or the cylinders need to be cleaned up with a hone. Some overheated rings you can nearly tie in a knot!

Severe blow by I pulled a 6.5 out and it had copper showing the the bearings and worn out rings. The 2nd had break in coating on the top half 2nd ring from not seating or improper assembly.

Best way to fix it is to deglaze the cylinders with a set of gapless rings put in.

 

[bison]

This much blow by is a bad idea to vent to the road! When you get off the freeway you will have so much blow by coming out of the tube your truck will look like it is on fire!

So ask yourself if you really NEED to fix it? I have only bothered on mine because the engine was leaking oil bad out the front seal from shot bearings. (And the other ate a foreign object requiring heads and pistons...)

AUTO RX etc. can free up stuck rings. Otherwise they are worn out, overheated and lost their tension, never broke in properly, or the cylinders need to be cleaned up with a hone. Some overheated rings you can nearly tie in a knot!

Severe blow by I pulled a 6.5 out and it had copper showing the the bearings and worn out rings. The 2nd had break in coating on the top half 2nd ring from not seating or improper assembly.

Best way to fix it is to deglaze the cylinders with a set of gapless rings put in.

It worked super on my wife's 98.before the road tube it was drinking as much oil as diesel,.afterwards only a ltr or 2 oil between changes.
She put another 100 k on it afterwards,the counter reads now 418000 km.
Yeah it smokes a bit underneath,....who cares?

 

[Big T]

It worked super on my wife's 98.before the road tube it was drinking as much oil as diesel,.afterwards only a ltr or 2 oil between changes.
She put another 100 k on it afterwards,the counter reads now 418000 km.
Yeah it smokes a bit underneath,....who cares?

Why would venting it to the air result in any different oil consumption than running it back through the intake? Is the intake sucking more blow oil out of the engine than otherwise dumped into a road tube.

 

[WarWagon]

Um... even the headlight smoked on that engine with a road draft tube. It was bad enough to have to care because the truck looked like it was seriously on fire. The engine was worn nearly to the point of spinning a main bearing when I pulled it.

I will agree that changing the pressure can affect the amount of oil vaporized.

 

[ak diesel driver]

Why would venting it to the air result in any different oil consumption than running it back through the intake? Is the intake sucking more blow oil out of the engine than otherwise dumped into a road tube.

IMO where they tie it into the intake boot is too close to the turbo and creates excess vacuum in the crank case. Literally sucking the oil laden fumes out of the engine rather than just capturing with a slight vacuum.

 

[Cali6.5]

IF the original issue was smoking orifices then wouldnt going to atmosphere (less vacuum from the intake) make more smoking from the other orifices? If the intake pulls a vacuum then that would decrease the amount of blowby coming out of the dipstick, wouldnt it? I have blowby comingout of my dipstick as well (225K mi) but it doesnt appear to burn oil.

 

[dangerousdave]

I tried the road draft tube and it increased the oil drips under the engine.
Then I went to a longer, larger diameter tube from the tuna can and decreased the oil consumption and eliminated the drips.
Increasing the ID of the flow from the CDR decreasec the velocity, given the same vacuum, the long inclined tube I have from the CDR to the turbo allows liquid flowback to the CDR, IMO.


I tried a lot of things on Cummins and Cats when I drove class A commercial. Each motor is different, whatever works for you.

If the motor needs a rebuild, what to you have to loose by trying some additives? Just saying...

I can't find any pics right now and have to run up to San Diego, maybe later.

 

[GM Guy]

so my 93 at a low stumbly idle puts out a tiny waft with the oil filler cap off, and at normal idle it doesnt put any out. I take it i am in great shape? stock CDR system.

how much blowby does it take to overpower the CDR at idle? as in if the CDR cant keep up, how bad is it, and if the CDR can keep up, just how much is still getting ran through?