Crankcase ventilation discussion and sort of survey - Page 3

**M2cupcar** · 6-2-07, 19:05

My catch can is made of 2" pvc connectors (two caps/plugs and a junction), 3 brass 90° fittings (in, out, drain) and some of that crinkle black plastic paint. Less than $10 total. I used the pvc parts to keep the can small- fits behind my headlight over the fender.

**fredio54** · 6-2-07, 19:52

i laid my pvc one out with the feed (from engine in the side lower down) and the return (to intake) at the top. also with the drain in the bottom as discussed. i filled it with brass cleaning scrubs and in this way, there is minimum chance of the oil making it uphill through the matrix...

fred.

**M2cupcar** · 6-3-07, 13:08

Just came back for running errands only to be greeted by a new oil spot (oil pan has a leak too) on the garage floor.

I feared the can had been leaking because it was full. Fortunately that wasn't the case- it looks like it was leaking around the brass fittings. I emptied it and probably got 2-3oz out of the can. I'm not sure if this is unusual because I can't remember the last time I looked at it with any seriousness. I have been making a lot of boosted runs lately - with peaks as high as 17psi and falling. Probably equal to a solid 15psi run for 3500 rpm every time I datalog for tuning. Based on experiences from other (turbo Mx5s) owners, they do see oil accumulation over a track weekend of a few oz. So I'm hesitant to panic, but that's hard not to do given this is my first turbo project. I'll probably do a compression check for my own sanity (as usual). Comments from those using a can for an extended period with higher boost?

Only a small bit of oil actually made it into the intake. No visible residue at the compressor intake. BUT this definitely brings to light the disadvantage of plumbing the breather back to the intake - if you get excessive crankcase pressure for some reason, it's going to pump oil into your intake, turbo, intercooler and possibly into the manifold. And it's not necessary, only ecologically responsible.

I think this might also reveal a couple of issues with my can - no packing/filter material to catch the oil, and small passages at the brass fittings (whatever 1/4" brass fitting ID is ~3/16" maybe). That's a big drop from the diameter of the OE breather bung on the cam cover. Thoughts/comments? - rob

**Just pulled the plugs and they all look normal, coolant is clear. Would have done a compression check but my gauge won't "peak and hold"

. I suspect what I'm seeing is normal.

**fredio54** · 6-3-07, 19:37

your engine is fine. dont panic! :-)

putting the two fittings so close together will not help the situation. i'll post a pic of my defunct one. currently it is a short pipe out the top :-)

and of course the idle pcv vac source.

yeah those fittings are small though. you can go a bunch bigger without changing thread size.

fred.

fred.

**fredio54** · 9-7-07, 11:45

http://www.mx6.com/forums/2g-mx6-for...questions.html (Oil catch can questions)

just linking this here incase it wasnt clear to someone reading why apart from dry sump the oem way per robs diagram is best...

fred.

Stroker · 9-7-07, 18:00

I run 2 1/2 inch pips from my sump to a oil air seperrature and on the botum of that there is a return to the turbo iol line works well im boosting over 30psi so you have to get the presure out off the sump .

**cam22t** · 9-8-07, 2:59

My plans were to fit a catch can into the breather pipes but i haven't got around to it.

So far i have the factory PCV still inplace and the RHS breather on the valve cover is linked up to the turbo inlet pipe. (just like factory).

I did noticed that when i drove to the drags last, i was on boost alot and then after a few runs at the drags, there was a bit extra than normal oil in the turbo inlet pipe.
I am not worried about this, as i was running 18psi the whole time.

When i have the time, i will put a catch can inline of that breather.

**fredio54** · 9-8-07, 4:40

dont forget to clean out all the oil thats in your intercooler when you do also. it makes a good insulator.

**chief tool** · 9-12-07, 23:21

Quote:

Originally Posted by fredio54

dont forget to clean out all the oil thats in your intercooler when you do also. it makes a good insulator.

Even tho I have a catch can on my GC (a factory one off an E5 turbo engined mazda) I still get oil in the intercooler...I havent worked out a way to stop it...I wash it out with kero, and then metho, then water every few months..

I only run 12psi..but I tend to drive it on boost as much as possible!

**fredio54** · 9-13-07, 2:33

although this suggestion will also make the on boost scavenging less effective, it will help stop oil making it out :

use longer hose.

i had about a foot and a half on each side of my custom pvc catch can, and never saw a drip of oil on the airfilter of the old ute engine post installation.

having said that, i also feel the need to question the effectiveness of the stocker catch can you have?

mine had a good sized fitting in the side at the bottom, and out the side at the top. it had a small fitting on the bottom that had a small hose to the dipstick hole, and it was filled with "goldylocks" course brass scouring pads. it also had a small filter on the top, but there was next to no chance of oil making it through all the goldylocks without falling downhill.

fred.

**carcenomy** · 9-16-07, 8:12

Why not go for Honda's F20C style crankcase ventilation? *cackle*

**matt89glturbo** · 9-27-07, 22:40

I am planning on running a catch can with a drain back to the sump when the turbo goes on...didn't realize so many were using catch cans, I was doing it experimentally, good to know all the good results...hopefully less than a month now

at least to get started on the installation...

**fredio54** · 10-5-07, 18:22

http://www.autoshop101.com/forms/h63.pdf

anyone that thinks that they know better than the oems should have a read through that. it explains the various modes of operation. things havent changed in a long time.

fred.

**matt89glturbo** · 10-13-07, 23:33

wow, I thought the fixed orifice system was a new thing...most of the domestics here in the US have just started using them in the past few years...toyota has been doing it for a while. Now that I think about it though, I suppose thats what the quad 4s in the early 90s were doing too

**gavin** · 10-19-07, 16:10

It occurs to me that the Honda folks have probably been running into scenarios where this is a need. So with that in mind...just a few examples of what they do.

Honda-Tech.com: Welding/Fabrication: Vented Valve Cover Post up some pics!

Gavin

6-2-07, 19:05	#31 (permalink)
M2cupcar Join Date: Jun 2003 Location: Atlanta, GA, USA iTrader: (1)	My catch can is made of 2" pvc connectors (two caps/plugs and a junction), 3 brass 90° fittings (in, out, drain) and some of that crinkle black plastic paint. Less than $10 total. I used the pvc parts to keep the can small- fits behind my headlight over the fender.
	\| 1990 Mx-5 \| Silver Red LE interior \| FE DOHC \| T3/T04e 57trim/.50AR Stage3/.48AR \| FM 1.6 LINK ECU with PLink & Palm M500

6-2-07, 19:52	#32 (permalink)
fredio54 Join Date: Aug 2004 Location: Auckland, New Zealand iTrader: (1)	i laid my pvc one out with the feed (from engine in the side lower down) and the return (to intake) at the top. also with the drain in the bottom as discussed. i filled it with brass cleaning scrubs and in this way, there is minimum chance of the oil making it uphill through the matrix... fred.
	DIYEFI.org - TRUE DIY engine management Mazda FE3/FE-DOHC Master Index Thread (work in progress) Mazda truck with FE-DOHC/FE3 "BIG like your house" Holset Turbo drinking 2.2 litres of fuel per minute ~= 385hp crank RIP SleepCounter :-( we will miss you! - RIP fredio54 :-( will we miss you?

6-3-07, 13:08	#33 (permalink)
M2cupcar Join Date: Jun 2003 Location: Atlanta, GA, USA iTrader: (1)	more on my can Just came back for running errands only to be greeted by a new oil spot (oil pan has a leak too) on the garage floor. I feared the can had been leaking because it was full. Fortunately that wasn't the case- it looks like it was leaking around the brass fittings. I emptied it and probably got 2-3oz out of the can. I'm not sure if this is unusual because I can't remember the last time I looked at it with any seriousness. I have been making a lot of boosted runs lately - with peaks as high as 17psi and falling. Probably equal to a solid 15psi run for 3500 rpm every time I datalog for tuning. Based on experiences from other (turbo Mx5s) owners, they do see oil accumulation over a track weekend of a few oz. So I'm hesitant to panic, but that's hard not to do given this is my first turbo project. I'll probably do a compression check for my own sanity (as usual). Comments from those using a can for an extended period with higher boost? Only a small bit of oil actually made it into the intake. No visible residue at the compressor intake. BUT this definitely brings to light the disadvantage of plumbing the breather back to the intake - if you get excessive crankcase pressure for some reason, it's going to pump oil into your intake, turbo, intercooler and possibly into the manifold. And it's not necessary, only ecologically responsible. I think this might also reveal a couple of issues with my can - no packing/filter material to catch the oil, and small passages at the brass fittings (whatever 1/4" brass fitting ID is ~3/16" maybe). That's a big drop from the diameter of the OE breather bung on the cam cover. Thoughts/comments? - rob *Just pulled the plugs and they all look normal, coolant is clear. Would have done a compression check but my gauge won't "peak and hold" . I suspect what I'm seeing is normal. Last edited by M2cupcar : 6-3-07 at 15:25. Reason: update*
	\| 1990 Mx-5 \| Silver Red LE interior \| FE DOHC \| T3/T04e 57trim/.50AR Stage3/.48AR \| FM 1.6 LINK ECU with PLink & Palm M500

6-3-07, 19:37	#34 (permalink)
fredio54 Join Date: Aug 2004 Location: Auckland, New Zealand iTrader: (1)	your engine is fine. dont panic! :-) putting the two fittings so close together will not help the situation. i'll post a pic of my defunct one. currently it is a short pipe out the top :-) and of course the idle pcv vac source. yeah those fittings are small though. you can go a bunch bigger without changing thread size. fred. fred.
	DIYEFI.org - TRUE DIY engine management Mazda FE3/FE-DOHC Master Index Thread (work in progress) Mazda truck with FE-DOHC/FE3 "BIG like your house" Holset Turbo drinking 2.2 litres of fuel per minute ~= 385hp crank RIP SleepCounter :-( we will miss you! - RIP fredio54 :-( will we miss you?

9-7-07, 11:45	#35 (permalink)
fredio54 Join Date: Aug 2004 Location: Auckland, New Zealand iTrader: (1)	http://www.mx6.com/forums/2g-mx6-for...questions.html (Oil catch can questions) just linking this here incase it wasnt clear to someone reading why apart from dry sump the oem way per robs diagram is best... fred.
	DIYEFI.org - TRUE DIY engine management Mazda FE3/FE-DOHC Master Index Thread (work in progress) Mazda truck with FE-DOHC/FE3 "BIG like your house" Holset Turbo drinking 2.2 litres of fuel per minute ~= 385hp crank RIP SleepCounter :-( we will miss you! - RIP fredio54 :-( will we miss you?

9-7-07, 18:00	#36 (permalink)
Stroker Banned Join Date: Mar 2005 Location: Sydney, Australia Age: 34 iTrader: (0)	I run 2 1/2 inch pips from my sump to a oil air seperrature and on the botum of that there is a return to the turbo iol line works well im boosting over 30psi so you have to get the presure out off the sump .

9-8-07, 2:59	#37 (permalink)
cam22t Join Date: Jan 2002 Location: Brisbane, Australia iTrader: (1)	My plans were to fit a catch can into the breather pipes but i haven't got around to it. So far i have the factory PCV still inplace and the RHS breather on the valve cover is linked up to the turbo inlet pipe. (just like factory). I did noticed that when i drove to the drags last, i was on boost alot and then after a few runs at the drags, there was a bit extra than normal oil in the turbo inlet pipe. I am not worried about this, as i was running 18psi the whole time. When i have the time, i will put a catch can inline of that breather.
	89 MX6. 4WS. FE DOHC Turbo. Garrett GT2876r Turbo. Wiesco Forgies. EMS 8860 ECU. 3 Inch Exhaust. Torsen Diff. 2500lb RX7 Clutch. 18 inch Rays Sebring ITC-S wheels. Cusco Camber Plates and Coilovers. Bosch 044 Pump. 750cc Injectors. 12.1 @ 116mph. 425hp (317kw) atw's http://au.youtube.com/user/cam22t

9-8-07, 4:40	#38 (permalink)
fredio54 Join Date: Aug 2004 Location: Auckland, New Zealand iTrader: (1)	dont forget to clean out all the oil thats in your intercooler when you do also. it makes a good insulator.
	DIYEFI.org - TRUE DIY engine management Mazda FE3/FE-DOHC Master Index Thread (work in progress) Mazda truck with FE-DOHC/FE3 "BIG like your house" Holset Turbo drinking 2.2 litres of fuel per minute ~= 385hp crank RIP SleepCounter :-( we will miss you! - RIP fredio54 :-( will we miss you?

9-13-07, 2:33	#40 (permalink)
fredio54 Join Date: Aug 2004 Location: Auckland, New Zealand iTrader: (1)	although this suggestion will also make the on boost scavenging less effective, it will help stop oil making it out : use longer hose. i had about a foot and a half on each side of my custom pvc catch can, and never saw a drip of oil on the airfilter of the old ute engine post installation. having said that, i also feel the need to question the effectiveness of the stocker catch can you have? mine had a good sized fitting in the side at the bottom, and out the side at the top. it had a small fitting on the bottom that had a small hose to the dipstick hole, and it was filled with "goldylocks" course brass scouring pads. it also had a small filter on the top, but there was next to no chance of oil making it through all the goldylocks without falling downhill. fred.
	DIYEFI.org - TRUE DIY engine management Mazda FE3/FE-DOHC Master Index Thread (work in progress) Mazda truck with FE-DOHC/FE3 "BIG like your house" Holset Turbo drinking 2.2 litres of fuel per minute ~= 385hp crank RIP SleepCounter :-( we will miss you! - RIP fredio54 :-( will we miss you?

9-16-07, 8:12	#41 (permalink)
carcenomy Join Date: Feb 2006 Location: Invercargill, New Zealand Age: 23 iTrader: (0)	Why not go for Honda's F20C style crankcase ventilation? cackle
	Moderator - one who arbitrates Dictator - one ruling absolutely and often oppressively Contrary to popular belief, these are not the same things...

9-27-07, 22:40	#42 (permalink)
matt89glturbo Join Date: Mar 2002 Location: Utah iTrader: (0)	I am planning on running a catch can with a drain back to the sump when the turbo goes on...didn't realize so many were using catch cans, I was doing it experimentally, good to know all the good results...hopefully less than a month now at least to get started on the installation...

10-5-07, 18:22	#43 (permalink)
fredio54 Join Date: Aug 2004 Location: Auckland, New Zealand iTrader: (1)	http://www.autoshop101.com/forms/h63.pdf anyone that thinks that they know better than the oems should have a read through that. it explains the various modes of operation. things havent changed in a long time. fred.
	DIYEFI.org - TRUE DIY engine management Mazda FE3/FE-DOHC Master Index Thread (work in progress) Mazda truck with FE-DOHC/FE3 "BIG like your house" Holset Turbo drinking 2.2 litres of fuel per minute ~= 385hp crank RIP SleepCounter :-( we will miss you! - RIP fredio54 :-( will we miss you?

10-13-07, 23:33	#44 (permalink)
matt89glturbo Join Date: Mar 2002 Location: Utah iTrader: (0)	wow, I thought the fixed orifice system was a new thing...most of the domestics here in the US have just started using them in the past few years...toyota has been doing it for a while. Now that I think about it though, I suppose thats what the quad 4s in the early 90s were doing too

10-19-07, 16:10	#45 (permalink)
gavin Join Date: Jan 2001 Location: santa cruz.ca iTrader: (1)	It occurs to me that the Honda folks have probably been running into scenarios where this is a need. So with that in mind...just a few examples of what they do. Honda-Tech.com: Welding/Fabrication: Vented Valve Cover Post up some pics! Gavin