How To: Change your stock PCV Valve and Venturi Set Up

[dougefresh_]

Part A: How to replace your stock PCV Valve.

Step 1: Remove Manifold, and all the attached wires, etc. There are several 'how to's on this, here's a couple: HOW-TO: Intake Manifold Removal and here How-To: Injector & Intake Manifold Removal

First thing I did was cover my intake runners with some shop towels, as I knew I'd be fighting with OCC hose under the car for awhile, and I work outside:



Current Matt Damond SM OCC Set up. Here are the two lines (pretty much on top of one another, and where they go). He has really good install instructs with his OCC kits:



The hose on the right is attached to the stock PCV Valve:


Remove the 8 bolts that hold the black box things to the crank case. Guess what size bolts? lol I left the hose there for reference.. that's you pcv valve and occ line (runs to top of OCC):


OCC hose detached from PCV Valve. This coolant hose kept getting in my way, so I took it off. Not too much coolant came out as my car was jacked up:


With that gone, I had super easy access to get the bolts off:


Here's the black box thing that holds your stock pcv valve:


Now comes the fun part! Getting this damn black plastic retainer clip off. It literally took me longer to get that off without breaking it than getting the mani and everything off. I still almost broke the damn thing! :


Success!!


Now just pop in your new OEM PCV valve, pop the retainer clip back in place, put the 8 bolts holding the black box thingy back in, and put the coolant line back on. If you took the coolant line off, make sure you snake it all the way on nice:



Part B: Making your OCC a 3-port Venturi set up.


Things you'll need:
Some OCC hose 6-10' to be safe (in case you replace some of your current hose or w/e).
One brass "T" fitting 3/4" all sides
One brass 90* elbow fitting 3/4" both ends
Some clamps (6-8 size for OCC hose)
Jegs Crank Case check Valve
1/2 NPT to 5/8" brass fitting

I have my SM OCC attached to one of my horn brackets. Here's what we're going to do:


Remove bolt holding OCC can to horn bracket to buy some wiggle room:


Remove Hose from bottom port of OCC, and replace with hose with T fitting attached. I clamped up everything I could tightly before running hose. I test fit once, and then cut about a 3" piece going to the "T" and then a longer section attached as pictured above. Now cut your hands to shreads as you jam that new OCC hose w/ the "T" fitting onto the BOTTOM port of the OCC. Be mindful of which way your clamps face, because there is very little room down there. Here is the "T" fitting attached to the BOTTOM PORT of the OCC:

^That view is from the ground up. You can see my OCC can off to the right. The bottom hose I added to the "T" fitting, and I had it face straight down. Attach a long section of hose to this, as this is the venturi line. Clamp everything tight!!!

Now, I didn't have a elbow fitting with my Jeg's Crank Case check valve, so I just added about a foot or so of hose to the mani. This allowed it to curve down without kinking. I also put a SURE mani spacer in while I was at it:


Here's a pic from below. You see the hose from the intake mani running down w/ the Jeg's CC check valve:


I need to connect these two hoses, as the one on the left goes back to the bottom port of the OCC:


So I cut one end, and put on my brass 90* elbow bend:


Cut the other piece coming down, and attached it to the other end of the brass 90* bend, and clamped everything tight:


I then snaked the excess OCC line to the exhaust about the frame, and zip tied it out of the way. I also used an 02 plug on the end, and clamped it tight so I don't have any leaks between now and when I see the welder:



Here's a short vid that sums it all up in a minute!

YouTube - ‪Mazdaspeed6 3-Port OCC Venturi Set up‬‏

YouTube - ‪Mazdaspeed6 3-Port OCC Venturi Set up‬‏

Big thanks to Silver Demon for recommending and explaining this set up, and taking the time to test multiple set ups to relieve excessive CC pressure. Thanks to Matt Damond for the help on the phone when I was about to take a hammer to that black clip! Thanks to Riggs for breaking down the PCV system to me a couple weeks back. My buddy actually installed the OCC while I was doing other shit, so I didn't even get to see wtf was going on, lol. Now I have

[4G63]

Your ridiculous my man! Once again an epic write up very well done sir and extremely helpful!

[ALIEN3T]

The black box if i remeber right is called "oil seperator"

[dougefresh_]

Originally Posted by AdrenalineRush Your ridiculous my man! Once again an epic write up very well done sir and extremely helpful!

Thanks man!! I don't think I have any 'how to's' left in me, lol. Silver Demon gets the credit for the method, I just documented it a bit with some pics. It's still kinda hard to see wtf is going on, but hopefully it help out the next nut job, lol. This install was a pita. I've had the mani off a few times and that was cake, but fighting w/ that damn pcv clip sucked, as did fighting w/ the OCC hoses under the car with zero room. It came out nice though, and I'm STOKED that I got it out of the way!! Now I just need to get that slash pipe welded on the DP, add the other Jegs check valve sitting here, clamp the venturi line to it, and voila! No more excessive CC pressure, and I can finally get to tuning the beast!!!

Sooooo sick of wrenching!!!!! lol

Originally Posted by ALIEN3T The black box if i remeber right is called "oil seperator"

That makes sense. I'm still gonna call it 'the black box thingy' though as that's how it was described to me, lol

[SilverDemon]

Nice write up Doug!! Take your time finding a location for the venturi pipe, nothing is more hateful than to find out that the pipe will not clear something after the welding is done.

[Tokay444]

Maybe I'm an idiot. Maybe I'm a noob, but I know the occ is there to keep junk out of the intake mani. How come the line going to the mani, which is supposed to be clean, below the line into the can, where all the shit comes in?

[dougefresh_]

Originally Posted by Tokay444 Maybe I'm an idiot. Maybe I'm a noob, but I know the occ is there to keep junk out of the intake mani. How come the line going to the mani, which is supposed to be clean, below the line into the can, where all the shit comes in?

The crankcase goes to the top port, and the mani to the 2nd port (normal set up). I'm splitting the line to the mani and adding a 3rd line to the DP.

Originally Posted by SilverDemon Nice write up Doug!! Take your time finding a location for the venturi pipe, nothing is more hateful than to find out that the pipe will not clear something after the welding is done.

Thanks man! I'm been thinking and worrying about exactly where to add the slash pipe. Care to take a peek at my DP, and give me your 2 cents? I know an outside bend is ideal, but both my 02 sensors are in there... the only place past the 2nd 02 is straight pipe. Is that full of fail? I know the OCC should catch everything, but I cringe more thinking about oil blowing over an 02 sensor :/ Here's my DP:

[Tokay444]

Oh don't get me wrong, see what you're doing, I'm just curious as to why an occ is set up like that. In my head it seems like you would want the clean side above the dirty side. But like said, maybe I'm just an idiot.

[jmhinkle]

Tokay, the way the occ is built inside means the dirty stuff comes in the top port and runs down a tube to bottom. The side port is in the top of the can above several baffles so the oily shit doesn't get pulled out to the manifold.

Sent from my ass using assatalk

[Tokay444]

Originally Posted by jmhinkle Tokay, the way the occ is built inside means the dirty stuff comes in the top port and runs down a tube to bottom. The side port is in the top of the can above several baffles so the oily shit doesn't get pulled out to the manifold. Sent from my ass using assatalk

Wicked. Thank you. That looks rite in my head now. I knew there was some type of medium in there for separation, but your description pieced it all together for me.

Sorry for the thread jack.

[dougefresh_]

Originally Posted by jmhinkle Sent from my ass using assatalk

ROFL

[MSP611]

good write up... im gunna have to do this when the top mount is being done... all this is going to be done at the same time...all this work is gunna take me a while... cant wait!!!

[dougefresh_]

Minor update. Fwiw, I checked my breather filter for the first time since my install (4K). I was told to change it or clean it every oil change, and I forgot all about it. When I peeped inside it looked brand fucking new! So that was pretty cool. I was expecting some oily bs in there, but I guess that Venturi set up is working quite well.

@SilverDemon

[SilverDemon]

Good deal Douge!!! I am glad to hear things are still running great!

[MSP611]

how r u attaching the occ hose to the DP... i know ur welding a bung/slash pipe to it, but wont it melt the tubing from the heat? or are u connecting some kind of brass fitting?

[jmhinkle]

The piece of slash pipe you get has threads on one end and the check valve screws on to it. The hose connects to the check valve.

[MSP611]

ooo thnks for the info @jmhinkle.... how do u get this so called slash pipe? are u guys just making them yourselfs?

[jmhinkle]

Here

I have an extra, but shipping will eat of most of the cost. let me know what shipping is from jegs and maybe we can work something out. I have a check valve if you need one too.

[MSP611]

god if only @MATT DAMOND would answer my PM's i could get his OCC with all the tubing and shit so i could do all of this, but nooooooo...

[jmhinkle]

Buy the parts yourself and save money. Order the OCC straight from SM, pick up a generic check valve/pcv from your local autoparts store (blow through it to make sure it works, I got two of the jeg's/Moroso ones that leak,) get the 5/8 pushloc hose from jegs and done. If you want to tee into the line to use the slash cut for vacuum under boost then you will need the pipe nipple a check valve from jegs and a generic 5/8 brass tee.

[MSP611]

im overseas i dunno if i can just pickup an generic PCV at a local autoparts store... i mean the language barrier doesn't help either lol... you order all this shit from jegs other than the SM catch can??

[jmhinkle]

Here is the best scenario (from my expericence) IMHO. Order the OCC from SM directly. Order an extra PCV from Mazda (all of $9, IIRC.) Order the hose from jegs (10 feet for good measure on a Speed6.) Buy a 5/8 tee, (9) 5/8" hose clamps and 1" of 1/2" clear tubing from any hardware store. Buy my slash pipe and 1 good check valve (out of 3 sitting here.) You will have the ideal system. OCC in the normal PCV path under normal conditions and vacuum off the downpipe or screamer pipe under boost. I can give you (or anyone) more details if desired.

[MSP611]

what size hose is it??? they had -06an, -08an and -10an??? will the SM catch can come with a bracket??? and which CC do i get looks like they had like 3-4 different ones available??

[jmhinkle]

an sizes are based on 16th's like this:
6an = 6/16 = 3/8"
8an = 8/16 = 1/2"
10an = 10/10 = 5/8"

You need 10an hose. I see Mr. Damond kind of cornered the market on the OCC kits even on the SM website. I've heard of a lot of people not getting email responses which is a shame if he wanted to make some sort of business from it. Email SM directly for a Stage 2 single OCC with 5/8th nipples. It comes with a piece of metal you can bend in whatever shape you want for mounting. Just mount it to the horn location and I don't think you even need the piece of metal, but it has been awhile so you might. I personally haven't found a better substitute than the stock PCV which is cheap, compact, made with a 90* bend, and the check valve always works. Only problem is that the small orange side is only 1/2". On the small end you can use a 1" piece of that cheap clear 1/2" tubing to make the difference or just clamp the 5/8" tubing down to it. Either way works. You clamp ~4" piece of the 10an hose on the large end and connect it to the intake manifold with the orange end facing down to the ground. Getting the piece of stock tubing off that goes from the intake manifold to the pcv box can be a bit tricky. Personally I recommend leaving it on the pcv side because I've seen people break the pcv trying to get that tubing off. Just put a 5/8" union in the end that originally went to the intake manifold and connect to the new tubing and then to the top pipe of the OCC. Connect side port of the OCC to the new connection on the intake manifold with the pcv in it. If you want to tee in the slash cut pipe do it in between the new pcv and OCC. The only other thing I recommend is unscrewing the backwards drain piece out completely and putting in a simple plug. It is a common npt size thread. The drain thing will eventually break off and it doesn't drain well and tends to get clogged.

[MSP611]

wow thts a lot of info to digest lol... ill see what i can come up with i still need all my dremel bits for my DIY intake mani port job and i need to find some studs tht will work for the injector seals since i cant order from fastenal becuz they wont ship to APO. also need a NPT plug to do the EGR delete.... u know wht size it is for tht tube for the EGR delete? then once i get all this shit i can put the car back together finally...

[jmhinkle]

I don't remember the size, but I know you can use a drain plug from an older cummins diesel (early 2000's) which most auto stores carry.

[dougefresh_]

I thought it was 1/2" NPT plug for the mani.

Originally Posted by jmhinkle I don't remember the size, but I know you can use a drain plug from an older cummins diesel (early 2000's) which most auto stores carry.

Joel get that avatar under control, lol

[jmhinkle]

Originally Posted by dougefresh_ I thought it was 1/2" NPT plug for the mani. Joel get that avatar under control, lol

I don't remember the size, but I know the original quick plug was the drain plug from a Cummins, lol.

See my sig. That's what I got with my 1 day ban for questioning the kool-aid.

[MSP611]

@jmhinkle do u have the slash pipe for the dp and the check valve tht i could get from you? would rather get from u than jegs if thts cool?!?!? so i just have to order tht hose after if i get tht stuff from u and call it a day. also ur using the moroso check valve correct? and if so is tht the replacement for the matt damonds one on his kits??

[jmhinkle]

I only use a Moroso check valve on the downpipe section. I still use an extra OEM pcv at the intake manifold. I bought several of those Moroso/Jegs valves and only got two that completely sealed so I'm only using the one.

[GLORIFIEDBOZO]

Gonna have to do this with new engine, thanks for the write up

[dougefresh_]

Originally Posted by GLORIFIEDBOZO Gonna have to do this with new engine, thanks for the write up

My pleasure Don't forget to pick up a new black plastic retainer clip for $8 when you get the oem pcv valve.

[GLORIFIEDBOZO]

Originally Posted by dougefresh_ My pleasure Don't forget to pick up a new black plastic retainer clip for $8 when you get the oem pcv valve.

lol I take you had issues with this?

[dougefresh_]

Originally Posted by GLORIFIEDBOZO lol I take you had issues with this?

Let's say that the words "FUCKING CUNT!!!?#$%@$" were bellowed across my parking lot on several occasion. It took me longer to pry that clip off without breaking it than it did to take off my mani and rig up my venturi set up. Very frustrating. I didn't know you could buy that part separate for $8, so I had no choice at the time. Others have fought with it, and there's a general consensus that's it's an abortion, and you should just buy a new one, and just carefully cut the old one off .

[TWOptSL0W]

@dougefresh
why not just eliminate the air going back to the manifold altogether? what about having the hose going from the dp straight to the pcv valve and even the valve cover vent?

does it not produce enough vacuum?

i have seen a bare block, and it seems like the black box thing covers that hole to the block to vent. how about making a metal plate (i think someone did) to cover it with just a port and no pcv valve. that way it goes straight to the exhaust and out.

[dougefresh_]

Originally Posted by TWOptSL0W @dougefresh why not just eliminate the air going back to the manifold altogether? what about having the hose going from the dp straight to the pcv valve and even the valve cover vent? does it not produce enough vacuum? i have seen a bare block, and it seems like the black box thing covers that hole to the block to vent. how about making a metal plate (i think someone did) to cover it with just a port and no pcv valve. that way it goes straight to the exhaust and out.

I think joel wilks made some custom oil separator with a bunch of other stuff going on, I forget now. I went with my current set up because @SilverDemon already tested a bunch of different set ups for evacuating excessive CC pressure, and this was the most effective. He has huge thread on it. I just read up, and went with this set up. It's actually pretty simple, didn't take long, wasn't too $$, and it has worked well for me.

I am sucking out some metered air, but it's just a matter of fuel trims, and then they were consistent. I'm guessing there isn't enough vacuum if you bypass the mani, but tbh, I don't remember. I researched, asked, installed, and forgot about, lol. My breather filter is in brand new shape (zero oil) after 5K miles, which says a lot though .

[GLORIFIEDBOZO]

Originally Posted by dougefresh_ Let's say that the words "FUCKING CUNT!!!?#$%@$" were bellowed across my parking lot on several occasion. It took me longer to pry that clip off without breaking it than it did to take off my mani and rig up my venturi set up. Very frustrating. I didn't know you could buy that part separate for $8, so I had no choice at the time. Others have fought with it, and there's a general consensus that's it's an abortion, and you should just buy a new one, and just carefully cut the old one off .

I have a magic screwdriver I use, gets it off super quick. First time a bit longer cause I thought it was a twist lock.

[SilverDemon]

Yup...Douge is correct, the venturi under low throttle is almost non-existent. I ran that way for about a week or so with a vacuum gauge hooked to the catch can, the needle would not move off of zero while in part throttle.

With the 2 check valves, the system acts as two separate circuits, low throttle input the check valve on the exhaust venturi is closed, and the intake mani check valve is open pulling vacuum on the catch can. Under boost, the intake mani check valve is pushed shut, and the exhaust venturi is pull open by the high velocity gases passing by the slash cut in the pipe.

[MSP611]

good info^^

[aaron_-01]

Could one possibly tie in daddy chinkus's vent valve method ( the one that vents from the valve cover) into this system as well? Or is that just a poor idea all together?