PCV Valve / Rocker Cover Breather

munday

munday

Member +
Yes thats true, but i still wouldnt want the minimal amount of oil vapour going back into the inlet, as well as octane dilution you will have a thin layer of oil covering the inside of the intercooler, doing no good for its heat exchange properties.

If you dont want to vent to the atmosphere (which is illegal) does your catch can have anything inside? If not i would buy some metal kitchin scourers (heavy duty so they dont fall apart from vibration) and stuff them inside to give more surface are for the oil vapour to condense on :beer:
 
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Gee

Gee

Member +
munday said:
Yes thats true, but i still wouldnt want the minimal amount of oil vapour going back into the inlet, as well as octane dilution you will have a thin layer of oil covering the inside of the intercooler, doing no good for its heat exchange properties.

If you dont want to vent to the atmosphere (illegal) does your catch can have anything inside? If not i would buy some metal kitchin scourers (heavy duty so they dont fall apart from vibration) and stuff them inside to give more surface are for the oil vapour to condense on :beer:
Click to expand...

Is this in relation to weejohn's setup? And I thought venting to the atmosphere was illegal..they way you have worded it, it seems you mean the other way round.
 
munday

munday

Member +
Gee said:
Is this in relation to weejohn's setup? And I thought venting to the atmosphere was illegal..they way you have worded it, it seems you mean the other way round.
Click to expand...

Not referring to any setup in particular :)

Edited my post to make it more clear, you are right i meant venting to atmo is illegal
 
Gee

Gee

Member +
OK screw this.

Going to get a catch can that does not vent to the atmosphere. I will put a PCV valve back in place as where it should be.

So, is WeeJohn's setup correct? Do I need a catch can with 2 inlets? Or what about this setup that everyone seems to use? Is this OK or not? The hose on the other side of the catch can goes nowhere, so is this still venting to the atmosphere?

DSCN2765.jpg
 
WallaceGlanza

WallaceGlanza

Member +
Your old setup is venting to atmosphere yes. I was going to have the same setup but put the second hose t-pieced into the pcv valve hose so it still had a vaccuum source as in the original way toyota had it setup.
 
Gee

Gee

Member +
Hmm..

I don't have a F'ing clue which is the best way to set a catch can up, you would think it would be simple, but there seems to be lots of different opinions on how it should be done.

Octane dilution can't be a good thing :s
 
munday

munday

Member +
Yes the way weejon has done it is fine, personally i would just vent it to atmosphere, i believe a dum valve that vents to atmo is illegal too so not as if you are going to get collared for it. But you could do as i suggested earlier and stuff a load of wire wool in there

WallaceGlanza said:
Your old setup is venting to atmosphere yes. I was going to have the same setup but put the second hose t-pieced into the pcv valve hose so it still had a vaccuum source as in the original way toyota had it setup.
Click to expand...

Can you just clarify what you mean on how you were going to run your setup? Do you mean instead of the hose venting to atmo yo would t it into the pcv? :)
 
Rory

Rory

Lifer
I have the PVC gutted, and running into the same line from the cam cover breather.
In turn, that line runs into the catch can.
The other port on the can i run a line from it, under the car and facing away from the airflow.
This in turn acts as a vacume, to pull the gasses out and leaves the oil residue in the can.

Simple yet effective.
See below,

DSC_0434.jpg
 
Gee

Gee

Member +
Oh I see what you have done Rory..cool.

Does this have the same effect as Little Johns? So yours is venting to the atmosphere too then?
 
munday

munday

Member +
Rory said:
I have the PVC gutted, and running into the same line from the cam cover breather.
In turn, that line runs into the catch can.
The other port on the can i run a line from it, under the car and facing away from the airflow.
This in turn acts as a vacume, to pull the gasses out and leaves the oil residue in the can.

Simple yet effective.
Click to expand...

The crankcase is always under positive pressure though, so no need for the line to be under the car facing away from the airflow
 
Rory

Rory

Lifer
@ Gee - Yep same effect.

@ Munday - I would rather not have the gasses being vented in an enclosed space....
It also helps pull the gasses out.
Every little helps. ;)
 
weeJohn

weeJohn

Lifer
munday said:
Yes the way weejon has done it is fine, personally i would just vent it to atmosphere
Click to expand...

My set up does not dump to atmosphere, have a good look at it.

Apart from the second valve, all I have done is split the hose that runs from the pvc valve to the inlet manifold, and put a catch can in line with it, that is what a catch can is designed to do, catch harmful vapours that could be sucked into the inlet tract.

Have a look here, I know its a Honda but bear with me lol

http://www.c-speedracing.com/howto/catchcan/catchcan.php

Gee if your hoses are welded onto the rocker cover, thats not a problem. Remove 1 and take the filter off the catch can and fit it to the end of that hose.
Block up the hole on the catch can.
Fit the short piece of hose that was connected to the inlet mani back on, with the pvc valve on it correctly.
Fit a piece of hose from the catch can to the end of the pvc valve that would have been inside the rocker cover.
 
weeJohn

weeJohn

Lifer
munday said:
But you could do as i suggested earlier and stuff a load of wire wool in there
Click to expand...

My catch can came with what is basically steel wool in it, I have seen others with a gauze that runsfrom side to side basically dividing the can into 2 halfs, with a spout in each half.

Its just an big empty can if its not like that, that will do very little.

Gee I see your can has 3 spouts. I was under the impression these were for cars that have a 2 compartment rocker cover, like the twin cam, or for v engines.

The reason not to connect the 2 spouts on the top of the rocker cover is to allow a flow of air when the engine is under vacuum. If the vacuum was onto the 2 spouts there would not be a flow of air through the crank case. Its like trying to suck on a straw with your finger over the end in comparrison to the straw end unblocked.

Rory judging by the colour of your hoses to the can, you dont get much residue in your can, or do you?
 
weeJohn

weeJohn

Lifer
munday said:
The crankcase is always under positive pressure though, so no need for the line to be under the car facing away from the airflow
Click to expand...


Thats not always the case munday, pressure changes in there as the pistons moving up and down causes air turbulence inside the block, so there is negative and positive pressure in there.

Gee do you get much residue in your catch can?
 
Gee

Gee

Member +
Only had this setup for a couple of months WeeJohn so not sure. Also, I can't open it..would have to take the filter off and look inside.

Think I am just going to get rid of my current setup and start again.

-Sometimes because of the filter venting to the atmosphere the fumes come into the car when the heaters are on.

-The welder has not done a very good job and oil is getting through tiny holes getting oil over the rocker.

-It is setup wrong anyway LOL
 
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