Denali08

I have an issue with RX catch can not collecting oil at all.

I have RX Catch Can w/ Dual Check Valve. RX Catch Can w/ Dual Check Valve

Initially, I used a Breather Oil Fill Cap with built-in, one-way check valve and it used to smoke at the back of the truck during long idle. Probably because of no enough vacuum and no vent out on valve cover or oil fill cap. So, I removed the internal check valve inside the breather fill cap and the smoke stopped for good. But the catch can would never collect oil while the fill cap filter get full of oil.

Now I put back stock oil fill cap because of the bigger turbo and I installed a small breather filter on passenger side valve cover. Still same issue, no oil in the catch can while pass side valve cover breather filter is full of oil and it splashes after WOT boost runs on the intake. Now, I have it extended with long 3/8 hose and placed the breather filter behind the front pass headlight where stock filter used to be. Now after WOT boost runs, oil is all over the front bumper pass side corner and pass front fender side.

The catch can has one of the dual check valves connected to the back of the driver side valve cover and the 2nd check valve connected to the intake behind the throttle body.

The none check valve tap on the catch can is connected to a hose barb fitting between the turbo and air filter for vacuum source when under boost.

Does anyone know why my catch can is not collecting oil and my pass valve cover breather filter splashes oil.

I am thinking my pre-turbo vacuum fitting connection is not pulling enough vaccum through the catch can because of the big 6" filter. I have seen the vacuum tap on some setups placed on the front comp housing of the turbo.

REDCYCLE13

iTrader: (6)

It looks like the vacuum source is too far away from the turbo impeller to see much vacuum. I run the same Rx catch can with my vacuum line immediately in front of the impeller. The fitting on the discharge will only see boost I believe.

Tootall

iTrader: (79)

you need to seal up you block . . . meaning no breathers on the valve covers to make the catch can work.

You also need a port pre turbo

Noah Burns

iTrader: (5)

use the turbo to "suck" from the catch can in turn sucking out of the crank case basically right Tootall?

Tootall

iTrader: (79)

pretty much, it's the only way to do it. After the turbo will only pull vac at idle

Denali08

It's already pre-turbo port, on the cold air inlet tube to the turbo.

I had it sealed with vented oil file cap with with built-in check valve meaning it would allow air in but not out of the pass side valve cover. It will smoke at idle.

REDCYCLE13

iTrader: (6)

You do have it in the intake, but it's too far from the turbo impeller. That's where the strongest vacuum is when the turbo is spooled up.

Choda

iTrader: (1)

I remember reading and posting in a thread about catch cans and someone said pre turbo vac source is not enough, especially at idle.

Denali08

At idle, it will get vacuum directly from the intake. The line between the catch can and intake is connect to check valved port on the catch can so that it will prevent boosting into the catch can.

Probably my intake did not have enough vacuum during idle and this cause the exhust smoke after long idle. This was resolved by puting a breather filter vent on the pass side valve cover.

What I'm after is why this breather filter splashes oil after WOT boost runs!!!

Do I drill and tap the front of the compressor housing to relocate the pre-turbo vacuume from the intake tube to the compressor housing for better vacuum source when under boost?

Also, it came to my mind that propably, my catch can is too small for the job. It has 3/8 lines but the taps on the catch can are diffently smaller than 3/8 ID. Maybe I should get bigger can with -8 or 10AN fittings/lines.

I might try connecting both valve cover vents with Tee to catch can. It should splash oil to catch can instead of the breather filter.

blownescalade62

For my setup I just ordered RX Monster catchcan and 1LE breather. Its recommended for over 9psi.