ok, this might sound like a dumb question, so im putting on my flamesuit now:

for all you guys running catchcans and/or catch cans with a pcv setup..what are you doing with the hose going from the charcoal canister to the center iron?? for intance, say we follow this set up (pic by pvillknight7 in another thread):



the center iron nipple now goes to a catch can, so what happens to the hose/line the WAS there that leads back to the charcoal canister? is it capped? thanks

 

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/crankcase-vent-906841/

 

In stock form, the charcoal canister goes to the lower iron nipple via a T. I have found that this can push a lot of oil into the canister, which ends up dripping out the bottom and on to the fender. So T it into the upper nipple instead.

 

hmm...is this the same on an NA? i went and looked earlier and mine has NO tee...the canister (only speaking of the port which runs back to the iron) connects into a hardline which is secured to the firewall and then comes out to a rubber line which connects to the center iron, no tee.....

either way, so idealy then aaron i should tee that line (green line in image)into the blue line (in image) between the filler neck nipple and the pcv valve like so?

 

I'd keep the canister on the upper nipple in an NA application as well. It will help prevent oil from making it's way into the canister. Alternately, a check valve can be placed in the canister line but it is hard to find small weak check valves.

Edit...Yes, that last diagram you posted is correct.

Note that if you don't have a standalone, the "filter" on the catch can is actually a hose that goes from the can to the tube between the AFM and throttle body.

 

Haha that cheesy paint picture...when I drew it I was thinking of my S4 TII setup. I run an E6k and no emissions or charcoal canister.

 

thanks guys, i was just looking over other people's catch can setups to see what i would do with my own and started thinking about it. thanks again

 

My car has the charcoal canister removed. Is the charcoal canister absolutely necessary to have? I know I should probably get one, I just wanted to make sure first.

 

I don't have one either, and was considering integrating its function into the catchcan, just unsure as to the exact routing. Should the lower nipple on the center iron just be capped off?

 

Old post, but question pertains to it. In the picture above it shows a PCV in line for the canister/oil filler neck. Will a small one way check valve work for this? Is there any concern of it failing when the engine is boosted? I don't know of a vacuum source to use that won't see boost. My air filter is direct to turbo, so I can't put it in front of the turbo.

 

i know its an old thread, but i REALLY fail to see what the charcoal canister has anything to do with any of this
oil dripping out of the bottom of the cc? i think not
the cc is part of the evap system, which under 0 circumstances would involve oil
only thing the cc does is collect the fuel vapor from the fuel system (hence evap) and when the vent solenoid and control solenoid are activated, pumps those vapors into the intake system........
the pcv system and catch can i can understand being talked about, but the cc has nothing to do with either

Lloyd

 

I and the FSM beg to differ. See jpg from........the FSM

 

Normally you would be right, but the FC is too primitive. On the FC the crankcase ventilation system and evaporative emissions system are Tee'd together because it is simpler and cheaper than having two independent closed systems. If you are doing emissions reduction there really is no need to connect them together. You can vent the evaporative emissions system completely but retain the PCV valve. You could also vent the evaporative emissions system and delete the PCV, running both crankcase vents to an open-vented catch can.

Usually on 90s and later cars (such as the FD) there is an evaporative emissions solenoid which controls flow of fuel vapors. The solenoid is duty controlled, like a boost control solenoid, to regulate the flow. Here is a diagram of the FD evaporative emissions system:



Notice that it is completely separate from the 1992-1994 FD crankcase ventilation system (FD only has a filler neck vent):



95+ FD had no PCV valve.

 

can i use a charcoal canister 89 on a fc 86?