Blowing out oil from the dipstick when on the dyno??

[MDCmotorsports]

You must run a vacuum on the crankcase! If you don't, you'll have:

-Poor turbo performance. Most likely a leaky, smokey turbo that doesn't live long.
-Blow by on the piston rings
-Poor sealing or blown fron and rear main seals

If you're TB doens't have a vacuum port with a one way check valve:

-Run two dash 8 or 10 lines off the top of the valve covers into a sealed catch can. Make sure these lines are off the BOTTOM of the can.

-Run one dash 10 or 12 line to the intake off the turbo. Make sure this line is at the TOP of the can.

 

[ATL88Supra]

You must run a vacuum on the crankcase! If you don't, you'll have:

-Poor turbo performance. Most likely a leaky, smokey turbo that doesn't live long.
-Blow by on the piston rings
-Poor sealing or blown fron and rear main seals

If you're TB doens't have a vacuum port with a one way check valve:

-Run two dash 8 or 10 lines off the top of the valve covers into a sealed catch can. Make sure these lines are off the BOTTOM of the can.

-Run one dash 10 or 12 line to the intake off the turbo. Make sure this line is at the TOP of the can.

guess thats why my rear main seal leakes

 

[marc3]

-Run two dash 8 or 10 lines off the top of the valve covers into a sealed catch can. Make sure these lines are off the BOTTOM of the can.

completely at the bottom , or like half way. cuz once the oil accumilates, wouldn't it block those hoses, or just check it more frequently and make sure it's not blocking the entry.thanks!

 

[WhtMa71]

Like everyone else said..Fix you PCV system...
Oh and when i used to be into DSMs, i noticed a few companys that make a spring to hold the dipstick in the tube because for some reasome even with a proper PCV system, it would blow the dipstick out at high boost usually >20psi. This is on 4g63's btw.
Oh but before you go throwing parts at the problem,fix what you have been told to fix. :thumbup:

 

[Adjuster]

Have to chime in here.

For awhile, just ran a filter on the end of the hose, no vac to the TB, or valve cover vents, and as long as you don't run lots of boost, it works, most of the time.. however, upon adding more pressure/boost, you do blow oil out the dipstick, and the valve cover vents too.

Blowby the rings is normal, Excessive amounts is not, but some is normal. Your compression figures would indicate there is nothing wrong with your rings at the moment, but the advice to not run this way for very long is correct too. It can screw up your ring to wall seal, and then your compression will go down, and blowby problems increase.

So, to solve my problem, I added a quality oil seperator for a large air compressor setup. (About 50.00, but it will trap all the oil and allow me to run a nice sized line to the intake pipe, just before the turbo.)

On normal running, this provides all the vac the system needs along with the stock 88 TB one way vac fitting sucking on the valve cover vents. On boosting, the vac just before the turbo should be about as low as it can be on this engine, so in theory, it should draw out any blowby pressure from the engine, and keep my rings sealed up well, and prevent any main seal leak problems too.

So, cliff notes.
You need a hose from the intake pipe to your valve covers. You can put a catch can there if you want, or use a oil seperator if you want, but either way, you need to hook it up to stop the problem.