Excuse the noob question but I need help to where to connect the hoses for my temporary oil catch can. I have one line connect from the OEM oil filler neck nipple to the "IN" side of the catch can. I had "OUT" line connected into the nipple of the UIM. I disconnected UIM hose to the catch can because there was a squeaking nose coming from the UIM. I capped the UIM nipple.

I have seen some people run the "OUT" hose to a nipple on a intake pipe connected to the turbo, but I don't have that. I have a cone clamped directly to the turbo.

Am I able to cap the "OUT" side of the oil catch can( its not vented)? Or what other options do I have to connect the "OUT" side of the oil catch can. Again ,this is just a temporary set up but I still don't know where the lines should go.

 

Lower Oil filler neck nipple to in on the can and then leave the out open

Lower oil filler neck nipple to in on the can and run the out to the intake somewhere

lower oil filler neck nipple to the in on the can and run the in to the stock location on the intake manifold with a check valve

theres no "wrong" way to install it unless you install it wrong. If the can is vented then you can run both oil neck nipples to the can. In or out doesn't matter. The whole point of the can is to provide a relief for crank case pressure. With that in mind it must have a vent or relief in the path somewhere and not be subject to positive pressure.

 

With the stock oil neck I recommend plugging one nipple and running the second one to a catch can. The can itself must be vented. A sealed system will not work if you eliminate the second path that dumps into the stock turbo inlet. Pop off the cap you have on there and get a small breather filter. The nipple you have circled on the intake manifold under the throttle cable bracket is supposed to go to the brake booster. Hook that back up or you will have no brake assist. I would also re-route the hose going over the downpipe. It is likely to fail from heat.

 

The FSM outlines how the stock PCV works. Rob Robbinette did an early write up on blocking the PCV that goes from the filler neck to the TB and installing a catch can in the line that goes to the primary turbo, https://robrobinette.com/pcv.htm. I followed this procedure with a non-vented can in the line to the turbo. It filled up quickly at the track. Later, I changed my oil cap to an aftermarket cap that had a plug in the middle, why, who knows. Anywho, that plug blew out at the track and spewed oil everywhere in the engine compartment. While the can was vented to the turbo, there was still significant crankcase pressure to blow out that plug. I have since changed to a vented catch can (still routed to the turbo), and my blow-by is next to nothing. I am sure the oil i was initially catching was caused by the crankcase pressure. Bottom line, use a vented can regardless how you plumb it

 

https://www.rx7club.com/3rd-generati.../#post12314769

That Jaz catch can is the way to go. Read for more info.

Dale