Maybe that's not too clear.

The intermediate housing has a large cavity b/t the faces on the front and rear side of that housing.

That large cavity collects blowby and oil from the journals.

It's gotta go somewhere and there are two exits from that cavity. One is the small pipe on the top of the housing and the other is a hole at the right bottom of that housing that leads straight to the pan area.

The oil filler hole has no connection to the small pipe except thru the pan area..

 

Ah, that's what I wanted. So peejay was right, you want to suck air in through one connection and out the other.

Thanks man, time to go rethink my planned PCV system...

 

thanks for all this information guys i was having the same problems and was just sitting here on the side lines waiting for you to come to a conclusion.

also can i use just any old PCV valve from an autoparts store?

also where should i tap into the intake manifold because i done think that one of the small vac lines is going to cut it.

 

Dammit...Sigh, I guess I have to rethink mine as well.The plan is now to run a line from the TID to the gallery nipple, then run the oil neck nipple to a T that connects to the purge valve and charcoal canister.

As for the fuel system being the cause blowby, not a chance. If you were running very rich then you're washing the oil film off the housings and reducing the sealing effect of all seals (and wearing them out much more quickly) but that's the only way fuel can cause blowby.

What are your side seal clearances (if you assembled the engine)?

 

So the gallery nipple you are referring to is the one on the middle iron behind and below the oil filler neck?

If that's the case this is how I solved my blowby problem:

I drilled and tapped a fitting into the TID and ran a line to the oil fill neck (this helps to suck the oil vapors out while you are building boost/in boost). That alone didnt fix it. I added an extra line Tee'd into an intake manifold source with a one way check valve to the crankcase vent on the center iron right behind the oil filler neck and and that finally solved the problem in addition to what I have said above (manifold vac helps to pull out oil vapors when in decel and the one way check valve prevents boost from pushing more pressure into the crankcase).

I havent had to rig up a catchcan yet but may do it soon. Driven like this on the track and it's proven true in my case

 

wow this is alot of info to take in Thanks everyone for contributing. Hey ilike2eatricers, do you have a pic of your setup? I did what i thought was what you did but I got a butt load more blow by after doing this. Also Aaron my clearances between side and corner seals where .25mm on each.

 

dont have a pic but i guess I could snap one tonight but just try and visualize this for now:

- 3/8" fitting tapped into the TID about 2" from the turbo inlet with a line about 3/8" ID running from the fitting behind the alt and around the oil filler neck to the nipple on the iron
This line is basically always sucking even moreso during boost

- nipple on the oil filler neck with a 2" long hose and one of the stock PCV one way check valves (found on stock TID) going to a tee to a manifold source nipple (or better yet if you have an open manifold vac nipple so you dont have to tee). I should mention that I'm using an NA oil filler neck not that it really matters much anyway.
This one only sucks at idle and even moreso during decel/engine braking (manifold vac is very strong) and the one way check valve stops boost from being pushed into the crankcase.

So in this case there is pretty much always a strong force pulling vapors from the crankcase. Ideally I should rig a catchcan to try and catch all the vapors with some kind of filtering so they will solidy again into fluid and minimize any chance of oily residue in the TID and IC pipes.

 

ahhhh ok thanks. I have a line going from the tid to the top oil filler neck and then from the center iron to a vac source with the check valve inbetween them.

 

Hmm Here is a FSM pic I modded a few years ago. IS this backwards or am I not able to read right tonight?lol


Another thing to mention about blowby/smoking exhaust....
Turbo's which have been rebuild can do this.
I don't know what BNR does but my builder had to remove and in the process destroy the internal restrictor pellet.

The turbo without this would smoke like a fiend when I drove.

I think i used a 3/16 restrictor on my feed line to compensate for this.

 

I know your pain. Read my experience, I drilled a 1/16" hole in my home cut gasket as a restrictor https://www.rx7club.com/showpost.php...28&postcount=9

As for the diagram I dont remember if I tried doing it how the diagram explains it but apparently hondahater has and it didnt work for him but it seems to have worked for you?

 

yeah here is how I did it and it seems like i got a butt load more blow by however of course I never ran my car like I did durring the tunning session with steve kan with a hole afternoon of 2nd, 3rd, and 4th gear rolls. However I did not get any smoke on idle or boost so maybe it was working???? I'm mainly just trying to get my blow by issue solved. Anyways here is the pic.



edit: oh yeah and I didn't have a one way check valve on the tid. Oh and yeah I had bryan at bnr make me an oil line that restricts the oil flow. basically he welds the oil feed line closed then drills a very small hole in the turbo end to reduce the oil flow.

 

I dont have a one way check valve on my TID either but since the turbo is always sucking and never pushing I figured it would be fine... but I guess it wouldnt hurt to add one in also.

I like my ghetto fabulous home cut gasket with a hole drilled through it lol. Much easier and I can always change up the size if need be

 

hahah that IS ghetto fabulous, I like it I just used a prelude intake to make mine and it already came with a nipple on the tid perfect for this application Now to go try and get my hood up The cable must have broke or something cause it's not poping up and it's locked down so mannnnnnnnnnnnnnnn If it's not one thing it's the other, lol.

 

Is there any tension in the hood release? Try making sure the hood is fully locked and then have someone push down on it while pulling the release again

 

lol, there is no tension at all in the hood release. I thought it was strange after taking a drive today and when I went to pop the hood there was no resistance at all. So then I thought maybe it was just me not closing the hood all the way but nope it wasn't that either. Damn this sux!

 

I just checked the manual and it says that 0.15MM is the max standard clearance, 0.40MM is the limit. A little on the loose side but I doubt that's your issue. Mine are much looser then that...

As for the PCV system, according to the manual the TII has a vent tube from the TID to the gallery nipple that also Ts into the charcoal canister line. The NA connects that nipple directly to the charcoal canister without the vent tube. So it looks like we were both right (sort of). I guess Mazda added the additional airflow to cope with the blowby the turbocharger generates.

 

ok thanks Aaron for your reply i looked it up in the fsm yesterday as well just to be sure. It may be even smaller than .25mm as when me and sonicrat where clearancing the side seals the feeler guage was actually bending some times when we did it witch means it was very very thin, more so then the .25mm feeler guage. So the way I had it up above is wrong? should I be putting the line from the tid to the bottom nipple and then the line from the top nipple to a vac source?

 

I was using a 25 thousandths when I was doing them.

 

wtf? where you been foo? haven't heard from you in a while! so is 25 thousandths the same as .25mm? And where the **** is all my damn blow by comming from?

 

It looks like running a line from the TID to the lower nipple is correct.

 

I've been here, it's you who's been MIA!

(And no, .25mm isn't the same as 25 thousandths of an inch!) 25 thousandths is like... .065mm?

 

damn so that can't be my problem then. I don't know where the **** this blow by is comming from...