searched already!!! just a quick oil catch can question

[White Comet]

i hate creating threads for a topic that has been covered before, which i know this one has. i've searched and through all the posts im still not 100% on how to hook up the catch can. upon purchasing my car, it looked like this, w/ a breather

do i connect the oil catch can to the part of the "T" in the valve cover that has the breather or to the back part with the hose? if it goes to the hose what do i do w/ the preexisting hose?

i think i have the other hose from the catch can right (correct me if i am wrong), but it goes to the intake tubing, correct? if it matters or anyone cares this is the catch can i went withhttp://www.frsport.com/Circuit....html

thank you for all ur help.

[Tr0uble]

With the breather at the front of the T disconnect the black hose at the back of the T. Run a hose from the back of the T to one side of the catch can. Then run a hose from the other side of the catch can to the hose you disconnected. If you don't have a male/male connector to hook the hoses together then pull off the black hose where it mates to the bottom end and hook the catch can hose to there. Whichever appeals to you visually. Personally i'd purchase some silicon hose colored to your tastes and hook it up.

[White Comet]

ohhh, thanks man. i could have sworn u hook one end up to the intake though? hmmm maybe i read the other posts wrong

[Tr0uble]

ohhh, thanks man. i could have sworn u hook one end up to the intake though? hmmm maybe i read the other posts wrong

The reason why I say attach it like that is because if you have ever seen the stock catch can, it's hooked in that way. Check an SR20DET FSM and you'll see what I'm talking about. Or maybe you can google some engine pics and find it. Its black and bout the size of 2 boxes of 5.56mm AR15 rounds.

[Steve Lloyd]

ohhh, thanks man. i could have sworn u hook one end up to the intake though? hmmm maybe i read the other posts wrong

You are correct, he is not. From the factory there is a hose that goes from the T (where the filter is) to the intake. Whoever swapped your car removed that hose, but this is where you put your catch can. You want a vacuum source to pull through the catch can. The stock can relieves crank case pressure and the vacuum from the intake aids in that. The air is sucked up from the engine, through the factory catch can and into the intake. AS it is right now, you have no vacuum to suck the air from the bottom end.

I hope this made some sense............

[White Comet]

made perfect sense, thank you both for your help

[nicku]

I have the same problem. I got my car with the factory catch can. But the other side of hose where the breather is in this picture, there is nothing. just an open hose. Should I connect back to the intake or put a catch can there?

[cheapscheisst]

I have the same problem. I got my car with the factory catch can. But the other side of hose where the breather is in this picture, there is nothing. just an open hose. Should I connect back to the intake or put a catch can there?

it goes to the intake tubing

[jdm180]

the way i have mine set up is there is a hose from where the breather is on the T vavle and it goes straight into my catch can. and thats it. easy as that. if you want to reroute it back which there is no point really IMO then the other side of the catch can should be a hose that goes back to the stock position.

[nicku]

i am kinda confused now. mine is one side of the T goes to the stock catch can. and the other side of T is an open hose. Its supposed to go to the intake tube, but the intake tube is plugged by something. should i just connect it back or should i put the other catch can there?

[jdm180]

the way i understand it works and how mine is set up is like this.

on the T fitting one side that is facing the firewall goes back into the block. the other side facing the front of the car goes to the catch can. the can should have 2 opening one to take the hose from the T fitting and the other to go back to the intake.

[nicku]

mine stock catch can is right in front of the firewall. and it connects to one side of the T ...and the other side which is closer to the front of the car is open. and is it supposed to conncet to the intake tube or another catch can?

[jdm180]

i would say either or is good. people just use the other catch can as a place for oil/sludge to go. you can just let it go to the atmosphere but if you have a lot of blowby it could leak on the ground.

oh and if its open meaning the T fitting has nothing on it on that side that is not a good idea cause oil can leak on somethin hot and start a fire. just connect some garden house and re route it. **** i used to put it into a soda can before i finally broke down and bought an actual catch can.

[nicku]

okay...i think you didnt get what i mean...the T got two different hoses on it. one side which is close to the firewall is connected to a stock catch can. the other side is supposed to connect to the intake tube, but it is not for some reason. I dont know why, the car came like that with oil splash all over. should I connect it with a new catch can or connect it back to the intake tube?

[jdm180]

i understand what you are saying and you can do either or.

[IanS]

this is how it should be hooked up, if you dont have a catch can, just run the front line straight to the intake tube. The other side of the tee should be connected to the factory oil seperator.

as Steve mentioned earlier, the line is connected to the intake tube to create a vacuum in the crankcase, this vacuum helps equalize the pressure helping the piston rings to do thier job, without vacuum the piston rings can wear prematurly causing excessive blowby. Connect it or fail

[jdm180]

i like your art work hehe j/k yeah that is what i was trying to explain but its easier with pics sometimes

[Tr0uble]

You are correct, he is not. From the factory there is a hose that goes from the T (where the filter is) to the intake. Whoever swapped your car removed that hose, but this is where you put your catch can. You want a vacuum source to pull through the catch can. The stock can relieves crank case pressure and the vacuum from the intake aids in that. The air is sucked up from the engine, through the factory catch can and into the intake. AS it is right now, you have no vacuum to suck the air from the bottom end.

I hope this made some sense............

Check the pics dude. Hooking the catch can up your way is bogus.The engineers at nissan designed for the stock catch can to be where it is.

Do this. Get a cup of water with a straw and carry it around with you. When you start feeling thirsty blow into the straw instead of sucking on it. Do this for a whole 9 days with this being your only source of liquid and see what happens. Imagine your stomach being the catch can. Ask yourself this... how much fluid did I collect?

Hooking the catch can up your way serves absolutely no mechanical purpose.

[jdm180]

i dunno bro. i think you are way wrong. any car that i have seen with a catch can has the hose coming off the front on the T valve(the part facing the front of the car)go to the can. i have never ever seen a hose connecting to the catch can from the back(part facing the firewall) of the T valve.

[White Comet]

i'm not sure who to listen to, although i do like the cup and straw analogy lol

[Steve Lloyd]

Check the pics dude. Hooking the catch can up your way is bogus.The engineers at nissan designed for the stock catch can to be where it is.

Do this. Get a cup of water with a straw and carry it around with you. When you start feeling thirsty blow into the straw instead of sucking on it. Do this for a whole 9 days with this being your only source of liquid and see what happens. Imagine your stomach being the catch can. Ask yourself this... how much fluid did I collect?

Hooking the catch can up your way serves absolutely no mechanical purpose.

So why then did the Nissan engineers design the front of the T to hook up to the intake?? You must have a magic engine if you can get vacuum from your valve cover. Every vacuum source I've ever seen on ANY engine is on the intake. The valve cover has no way to create vacuum like you illustrated in your picture. Do you understand how the PVC system works?? There is a check valve in the PVC so that air doesn't flow INTO the valve cover area, so why would the catch can system blow INTO the valve cover?? Aslo, if the valve cover created vacuum(suction) how would the check valve ever open?? The valve cover is pressurised(blows air) and the PVC system relieves this pressure.

[nicku]

now...im confused!!! what am i supposed to do? since the back of the T has the stock catch can...should i just connect the front of the T back to intake?

[White Comet]

or an aftermarket catch can (from what ive been told)

[White Comet]

thank you all for your input, i just installed mine today and will post pictures shortly. just to let anyone know if u go w/ the same catch can i did, the hose they provide is just a little too tight to go over the t fitting on the valve cover. a quick run to pepboys and i picked up a little larger diameter black hose. fits like a glove and it looks more stock than the clear hose provided.

[Tr0uble]

So why then did the Nissan engineers design the front of the T to hook up to the intake?? You must have a magic engine if you can get vacuum from your valve cover. Every vacuum source I've ever seen on ANY engine is on the intake. The valve cover has no way to create vacuum like you illustrated in your picture. Do you understand how the PVC system works?? There is a check valve in the PVC so that air doesn't flow INTO the valve cover area, so why would the catch can system blow INTO the valve cover?? Aslo, if the valve cover created vacuum(suction) how would the check valve ever open?? The valve cover is pressurised(blows air) and the PVC system relieves this pressure.

Jesus dude. Look what the PCV line runs to. The Intake manifold. Vacuum pressure is located there. Its not a magic engine. Look in the picture. The stock oil catch can is located at the back of the T. Crack open an FSM and look at the Vacuum Diagram.

This is what you said- "Every vacuum source I've ever seen on ANY engine is on the intake."

My response- I say again, Look where the PCV is hooked!!!The Line from the valve hooks directly into the top of the intake manifold.

This is what you said- "So why then did the Nissan engineers design the front of the T to hook up to the intake??"

My response - To burn the fumes from the crack case. The whole purpose of a catch can is to separate out the oil so that the fumes can be burned in the combustion chamber. The vacuum created is greater than the pressure of both the crankcase blow by and valve cover blow by combined. Without relieving this excess vacuum problems would occur.

Why even have those oily fumes flowing through your intercooler/intake in the first place? When the fumes can be sent the same way the fumes produced in the valve cover are burned.

Just hook the catch can like I said so the fumes flow through the valve cover through the pcv and into the combustion chamber via the intake plenum runners.

This will save your Intercooler and inlet turbine from getting mucked up.Remember this. Fumes still contain residue from whatever it burned off from.

Just a little FYI, I do know how a PCV works. The question is DO YOU??Obviously not by this statement.This is what you said - " There is a check valve in the PVC so that air doesn't flow INTO the valve cover area, so why would the catch can system blow INTO the valve cover?? Aslo, if the valve cover created vacuum(suction) how would the check valve ever open?? The valve cover is pressurised(blows air) and the PVC system relieves this pressure."

My response - Taken Straight from the PCV section of my LS1 ASE Engine Performance Booklet

The PCV (Positive Crankcase Ventilation) valve (along with the Breather Element) re-circulates unburned gases back into the engine to be re-burned, cutting air pollution. A plugged PCV can cause rough engine idle and many other problems, including engine damage. It is quite important that the PCV value be working properly in your car. The PCV valve should be checked/changed every 30,000 miles.

First off lets look at the work check valve. This allows air to flow only in one direction. "how would it ever open" A check valve is always open unless air flows in the direction that it is not supposed to. It then closes to prevent this.Check Valve means one way flow. Sigh....

Next, Positive Crankcase Ventilation. Let's take a look at this. Hmm... How bout this helps ventilate the fumes/blow by gases created in the crankcase.

"Valve Cover is pressurized" Yes and No. Pressure is created by blow by from combustion, however the vacuum created by the intake manifold sucking on the PCV is greater. So that the unburned fumes can be recirculated back into the Combustion chamber to be burned to reduce pollution.These same fumes are "blew by" into the crankcase creating a positive pressure. Hence the need for a Positive crankcase ventilation system.

Seriously dude if you don't know what you are talking about especially something as simple as a PCV valve do us all a favor and don't give anyone mechanical advice.

I'm ASE certified. I know who's right and who's not. Do whatever you want. I'm not going to argue anymore.It's not my car.

On to the next topic.Peace out.

Modified by Tr0uble at 2:40 AM 8/18/2007
Modified by Tr0uble at 2:45 AM 8/18/2007

[Emperor_Tha]

my boy took his civic, 35r b18 engine, on the dyno on the first time and when he got full boost, oil would shoot out his dipstick. this was cause from the positive pressure that was build in his crankcase. he didn't have a catch can or any source to vacuum the pressure because all he had before was just a filter on the pcv nipple. now since he got a catch can, no more oil is shooting out.