How To: LD9/Ecotec Boosted PCV System - Boost Forum

Forum Post / Reply
You must log in before you can post or reply to messages.
How To: LD9/Ecotec Boosted PCV System
Sunday, February 01, 2009 12:01 PM
SweetnessGT
After my previous post about my phantom oil leaks, I decided to sit down and really think about how things have been functioning on my engine. After some research, I've drawn the conclusion the source of my problems is the Positive Crankcase Ventilation system.

My symtpoms:

- Phantom loss of LARGE amounts of oil. 1 quart every 200-300 miles
- Small oil drips under the car - source indistinguishable / unknown
- Oil leaking out of the TOP of my cam tower bolts
- Turbocharger oil seals blown twice in 3000 miles

As you can see, I had some frustration on my hands. When the engine was built both times, I went over the entire thing with a fine tooth comb, but managed to overlook the PCV system. This seems to be the source of my frustration after some careful thought.

Quote:

As an engine runs, gases and combustion pressure are contained within the combustion chamber and prevented from passing into the crankcase (containing the crankshaft and other parts) between the side of the piston and the cylinder bore by piston rings which seal against the cylinder. Worn or damaged piston rings or cylinder walls will allow these gases to escape past and directly into the crankcase. This leaked gas is known as blow by because the pressure within the cylinders blows it by the piston rings. In newer engines, and engines with new piston rings or reconditioned cylinder walls, this is often caused by failure to observe the correct "breaking in" procedure. If this blow-by gas could not escape then pressure would build up within the crankcase.

Before the invention of Crankcase Ventilation in 1928 the engine oil seals were designed to withstand this pressure, oil leaking to the ground was accepted and the dipstick was screwed in. The hydrocarbon rich gas would then diffuse through the oil in the seals into the atmosphere. It is therefore an emissions requirement as well as a functional necessity that the crankcase has a ventilation system. This must maintain the crankcase at slightly less than atmospheric pressure and recycle the blow-by gas back into the engine intake. However, due to the constant circulation of the oil within the engine, along with the high speed movement of the crankshaft, an oil mist is also passed through the PCV system and into the intake. The oil is then either burnt during combustion or settles along the intake tract, causing a gradual build-up of residue inside the inlet path. For this reason many engine tuners choose to replace the PCV system with an oil catch can and breather filter which vents the blow-by gases directly to atmosphere and retains the oil in a small tank (or returns it to the sump), although this technically fails to meet most engine emission legislation.


- Quoted from Wikipdeia. Link found HERE


As you can see, the PCV keeps the crankcase from pressurizing itself, since compression is made below the piston skirt as the engine rotates. Fresh air is mixed in to help with removing oil from the vapours and remove hydrocarbons. The PCV system on the LD9 is a BIT complex with the addition of an air/oil separator to further help separate oil from the vapours before they are re-introduced to the combustion process. Here is a diagram I have come up with:




As you can see, the green is the fresh air inlet. Under some conditions the PCV system can also use this as an outlet, but generally it is the inlet of fresh air into the system. Oil passes through the crankcase and is put through a series of complex baffles in the A/O Separator to help separate the oil vapours, which then drains back into the block via a hole. Unlike a standard PCV system which uses a PCV valve, the LD9 (and Eco) have a vaccum port cast into the block and head, which attach to intake port #3 via the intake manifold gasket.

With a stock LD9 or Ecotec intake manifold, this spells disaster, as you will be putting boost into the crankcase, reverting the system, and doing the exact opposite of what the system is intended to do. The weakest oil gaskets will be subject to leakage, as well as blow out. Front and rear main seals, valve cover/cam tower gaskets, and the turbo center section oil gaskets.

The most important part of the system, is the exit, which is cast into the head. Many of us who install H.O manifolds on the LD9 end up blocking this exit, giving the system no proper way to expel crankcase gases. The system reverts, and uses the fresh air inlet to do this, which is far from ideal. Add boost into this mix, and you end up with more presure than the system can handle, since it's supposed to use VACCUM to draw out the gasses as well as fresh air to help remove oil vapours before they exit the crankcase.


After some digging around, I realized a few things. This isn't just a problem for us, even stock boosted motors have issues with the PCV system failing. I turned to many stock boosted platforms with aftermarket setups, and it was the SRT guys that had the most complaints. The stock PCV is weak, won't stay shut tight enough under high boost, and fails under the extreme conditions of the PCV system. Plastic check valves were a no go - so they turned to Brass check valves with viton seals, which are a LOT more duarble under the PCV's conditions. They also crack at 0.3 psi so they open easily once the situation is right.

I then turned to the #1 source of 4 cylinder engine building - HondaTech. Those boys know how to fight high boost issues in a motor, and they didn't disappoint. I found a PCV system that they use, and modified it for my own purposes. Below is a diagram of my steup, a parts list, and a how to explaining each part and why I'm using it.





PARTS LIST:

(2) McMaster Carr 1/2" Brass VITON Check valves part # 7775K64 (Female on both ends)
(4) Male 1/2" NPT threading 1/4" brass barb fittings
(1) Male 1/4" NPT threadings 1/4" brass barb fitting
(1) 1/4" Brass barb "T" Fitting
1/4" Nylon hose
1/2" Nylon hose
(2) Catch cans (one with 1/2" inlet and outlet and one with 1/4" inlet and outlet)
(1) 1/2" inlet breather filter
Drill bit and Tap for 1/4" NPT
Teflon Paste
TURBO INTAKE (Optional)

The system is a bit more complex than usual, since I elected for a dual check valve system that would give me PCV ventlation during off boost AND boosted conditions. You'll notice that the outlet for the PCV is coming out of the air oil separator. After speaking with Brandon Fetter I found out he tapped his air/oil separtor right across from the hole in the block that leads up to the head. This is a LOT simpler and a lot more convenient than tapping the intake manifold flange on the LD9. On an ecotec you'll still have to tap the intake manifold flange with a 1/4" NPT 1/4" brass barb fitting, and block off the path from the hole to port #3 on the head.

Brandon if you read this, please post up that picture of your tapped A/O separator. Thanks man!

These instructions are assuming you have an LD9 with a stock intake manifold. If you have an H.O intake manifold with the stock 2.3 gasket installed, you have already blocked the hole in the head.

INSTRUCTIONS:

Remove the intake manifold. I won't get into how to do this, I assume you know how to undo bolts.

Look at the intake manifold gasket, you will see a little U that runs to port #3. Trim this part of the gasket off and use a bit of RTV or copper gasket maker to seal it up. Also put some metal gasket material with some copper RTV over the hole in the head to ensure it's blocked off. Reinstall the intake manifold. Your head port is now blocked.

Remove the air/oil separator.

Inspect it from the back and look at the baffling. Figure out where the hole needs to go in the air/oil separator so it is right across from the hole in the block.

Drill and tap for 1/4" NPT threading

Install your 1/4" NPT brass 1/4" barb fitting into the air oil separator. Use teflon paste to seal but don't use too much, you don't want it mixing with your oil.

Reinstall the air/oil separator. Use a new gasket if you feel the old one needs replacing.

Run a 1/4" nylon line from the fitting you tapped to a catch can with a 1/4" inlet and outlet. You can use an ebay catch can if you want, just make sure you stuff some very fine steel wool in it to promote the removal of oil from the air. I will be using an air-tool filter/catch system which is available from Sears or Home depot. It is used to collect water in air tool lines, simply remove the filter element out of it. It is 1/4" NPT in and out, and is compact.

Run a 1/4" nylon line from the catch can to your brass barb T fitting.

Run a 1/4" nylon line on the other end of the T fitting to your check valve. The McMaster Carr checkvalve is female on both ends with 1/2" NPT threads. Use 2 of the male 1/2" NPT brass fittings with 1/4" barbs on them, with a BIT of teflon paste so you can have barbs on each end of the check valve. (You will do this for the 2nd check valve)

Make SURE the arrow is pointing TOWARDS the intake manifold/vaccum source.

Run 1/4" nylon line from the outlet of the check valve to your vaccum source. I will be using a 1/4" port on my H/O intake manifold. Your vaccum source MUST have constant vaccum (i.e the intake manifold)

For the 2nd part of the system:

Run a 1/4" nylon line from the perpendicular barb on the T fitting to your 2nd check valve. Make SURE the arrow is pointing TOWARDS your vaccum source. (Turbo intake hopefully)

Run 1/4" nylon hose from the outlet of the 2nd check valve to the secondary vaccum source - hopefully the turbo intake if you have one. This source must NOT SEE BOOST.


The way this system works is the check valve by the manifold opens with the engine idling or in off-boost situations - due to the higher vaccum in the intake manifold. This is what you want from your PCV system, as it draws crankcase vapours out from the crankcase. It has a catch can in line to catch any vapours before they reach the check valve or the manifold, so the air should be as clean as possible. Because there is vaccum from the manifold, the first check valve is sucked open, but the SECOND check valve is sucked shut, so there is no vaccum leak.

As soon as you go into boost, the primary check valve will shut. Since there is now more vaccum in your turbo intake now, the secondary check valve will open, allowing crank cases to vent and pass through the combustion process properly. As soon as you let off the throttle and go out of boost, the primary check valve opens again, which in turn sucks the 2nd check valve shut.

This should allow for venting both in and out of boost.

The 2nd part of the system is the fresh air inlet (which is sometimes an outlet under the right conditions)


Run 1/2" nylon line from the left nipple on the air oil separator on an LD9, or from the valve cover vent on the Ecotec to a catch can with 1/2" inlet and outlet. If you use an ebay catch can, please stuff it with fine steel wool to promote oil vapours being caught in the can.

Run 1/2" nylon line from the outlet of the catch can to a 1/2" breather filter. Hide this so the cops/state or provincial inspector/EPA don't decide to have a bad day, open your hood, and get up your ass. This will give you the freshest air possible for the crank case. Sadly because it's also an exit sometimes, it's illegal to vent this to atmosphere.


And that's that. I would like to thank BlownBlack Z for helping me confirm a few things about the LD9 PCV system, PJ for staying up late with me to show me how the Ecotec system works, and Brandon Fetter for showing me his pictures of the tapped air/oil separator.

If anybody has any questions, go ahead and ask. I hope this helps to save some gaskets and turbos for some of you guys. I know mine's going in the garbage... but that's for a different reason. Hehehe.

-Chris-


-Sweetness-
-Turbocharged-
Slowly but surely may some day win this race...

Re: How To: LD9/Ecotec Boosted PCV System
Sunday, February 01, 2009 12:13 PM
Tinkles
A+

But now you have me alittle worried about S/Cing my eco.


Tinkles
v. intr.
1. To make light metallic sounds, as those of a small bell.
2. Informal To urinate.
v. tr.
1. To cause to tinkle.
2. To signal or call by tinkling.
n.
1. A light, clear metallic sound or a sound suggestive of it.
2. An act or instance of tinkling.


Re: How To: LD9/Ecotec Boosted PCV System
Sunday, February 01, 2009 12:31 PM
T3e Cody
Eco guys can just run a LSJ intake manifold gasket and that will seal up that port between 2-3.

I'm just going to run a breather filter off the PCV nipple and probably block that hole off with the LSJ gasket which the kit tells you to trim to make it match.

I haven't heard any eco guys running into problems with this issue you have. So i dunno, kool idea if it helps you but I don't think I will have any issues.



Re: How To: LD9/Ecotec Boosted PCV System
Sunday, February 01, 2009 12:41 PM
icemike89
Very nice writeup sweetness. I had a good idea of what needed to be done for the best setup but you just helped 100% with part numbers and all. I have a pic of Fetters tapped pcv plate saved somewhere lol. For the smaller catch coming off the tapped hose bard a fuel filter will work fine correct?


Re: How To: LD9/Ecotec Boosted PCV System
Sunday, February 01, 2009 12:53 PM
SweetnessGT
The ecotec supercharged setup uses the LSJ gasket as cody mentions... this blocks off the port. If you are gonna run an ecotec with a stock N/A manifold and boost you must tap the manifold flange so that you can put vaccum to that port.

If you run the GMSC M62 for the eco it blocks the port off - the supercharger has a vaccum port cast into the lower manifold which goes to the bypass area.

On the LD9 GMSC the manifold flange is already tapped, you run a vaccum line from the nipple to the bypass area on the charger.

No worries if you're going with GMSC stock boost, this is for guys who want to turbocharge with the stock intake manifold or the H.O manifold for the LD9 boys.

IceMike - I am using an air compressor line filter... I'll see if I can find a link to one. I heard about it online and went to home depot to check it out in person, really nice little piece and apparently it works well.

I simply wanted this system so I had venting under boost and off boost.

-Chris-



-Sweetness-
-Turbocharged-
Slowly but surely may some day win this race...
Re: How To: LD9/Ecotec Boosted PCV System
Sunday, February 01, 2009 1:59 PM
Ericsnow25
I have a s/c eco and the only place it leaks oil is alittle bit out of the PCV breather that I put on there....any better suggestions?


2005 LS Auto (Blue)
-M62 Kit with 3.1"
-ZZP S3 H/E setup
-Pacesetter armor coated header
-Magnaflow 22" resonator (p/n 10436)
-Vibrant CatBack
-TTR Upper and Lower motor mounts
Re: How To: LD9/Ecotec Boosted PCV System
Sunday, February 01, 2009 5:18 PM
LAFNGAS
hey chris, just wanted to bug ya but your checkvalve for the turbo intake side should be opening to the manifold thus allowing air to go through it and creating the vacuum is it not?








Re: How To: LD9/Ecotec Boosted PCV System
Sunday, February 01, 2009 5:38 PM
BuiltNBoosted
so for me to fix this i can just get the lsj intake manifold gasket? correct? and that goes between the black plastic intake manifold and the motor correct?



Re: How To: LD9/Ecotec Boosted PCV System
Sunday, February 01, 2009 10:57 PM
Roofy
I just made a small metal plate, and sandwiched it between the intake manifold and the pcv gasket. Only thing i noticed is a bit more oil in my oil catchcan, nothing to write home about though.




Currently #4 in Ecotec Forced Induction horsepower ratings. 505.8 WHP 414WTQ!!!
Currently 3rd quickest Ecotec on the .org - 10.949 @ 131.50 MPH!!!

Re: How To: LD9/Ecotec Boosted PCV System
Monday, February 02, 2009 3:32 PM
z yaaaa
i'd say STICKY but it'd never get done.



Needing 2.3 oil pump stuff? PM me...
Re: How To: LD9/Ecotec Boosted PCV System
Monday, February 02, 2009 4:56 PM
RyZ96
great write up.. Keep in mind, you can't really go to big for crankcase relief.

Read the build book, they suggest a -12 fitting welded to the eco valve cover, leading to a catch can. A lot of the fast/high hp cobalts and redlines run a breather oil cap available online.

personally I just had a -10 fitting welded to my valve cover to a custom catch can and atmospheric..

Honda-tech has GREAT write ups about crankcase ventilation, pro's/con's, how to's, why's and anything else you can think of







Re: How To: LD9/Ecotec Boosted PCV System
Monday, February 02, 2009 7:16 PM
Boosted2point4


i almost thought about adding 2 -10 bungs to the timing chain cover and run that to a catch can




R.I.P. Brian Klocke, you will never be forgotten
Re: How To: LD9/Ecotec Boosted PCV System
Monday, February 02, 2009 11:26 PM
Bpow
Looks good Chris....will you post some pics of the setup once you have it installed?



Re: How To: LD9/Ecotec Boosted PCV System
Tuesday, February 03, 2009 3:21 AM
jmarks82
Boosted2point4 wrote:i almost thought about adding 2 -10 bungs to the timing chain cover and run that to a catch can


I thought about doing the same the other day. Maybe next year...





Re: How To: LD9/Ecotec Boosted PCV System
Tuesday, February 03, 2009 7:11 AM
BuiltNBoosted
anyone have a pic of doing it on an eco? im confused on this i guess..



Re: How To: LD9/Ecotec Boosted PCV System
Tuesday, February 03, 2009 10:10 AM
BuiltNBoosted
Ok i talked to Chris on this and the problem with finding the check valve is they have to be the McMaster Carr and they are only available throught them. problem is, they are not accepting new accounts at this time. laffngas tried to order them and that is what they told him too. i tried and got the same response. GOOD NEWS IS.... my dad already has an account with them and we are willing to order them for the people who want and need them.

and a note, the correct part number for the female to female i s 7775K54, NOT 7775K64. just to clarify.

i need to know how many people will need these check valves so i can compile a list. i will not make anything off these. just going to get you your parts. they will retail for $22.33 and thats what you will buy them for plus shipping. and it will be CHEAP to ship.

this is purely for interest. no minimum but i dont want to keep doing single orders if i can help it.

Name, quantity, email, payment method
--------------------------
1. Vincent Morris, 2, Vink70_99@yahoo.com, paypal




Re: How To: LD9/Ecotec Boosted PCV System
Tuesday, February 03, 2009 11:45 AM
Mr.Choo
I am still confused on this. If anybody can make up a diagram of a s/c eco, that would make a world of difference. I do, however, understand most of the concepts
Re: How To: LD9/Ecotec Boosted PCV System
Tuesday, February 03, 2009 12:09 PM
BlackEco
Vincent Morris wrote:Ok i talked to Chris on this and the problem with finding the check valve is they have to be the McMaster Carr and they are only available throught them. problem is, they are not accepting new accounts at this time. laffngas tried to order them and that is what they told him too. i tried and got the same response. GOOD NEWS IS.... my dad already has an account with them and we are willing to order them for the people who want and need them.

and a note, the correct part number for the female to female i s 7775K54, NOT 7775K64. just to clarify.

i need to know how many people will need these check valves so i can compile a list. i will not make anything off these. just going to get you your parts. they will retail for $22.33 and thats what you will buy them for plus shipping. and it will be CHEAP to ship.

this is purely for interest. no minimum but i dont want to keep doing single orders if i can help it.

Name, quantity, email, payment method
--------------------------
1. Vincent Morris, 2, Vink70_99@yahoo.com, paypal



The other option which may not be better but a lot cheaper is to get the valves from the yard. A couple months ago I grabbed the entire PCV system off a boosted SAAB including all the check valves I need for practically nothing. Plan on putting it together before season stars this year so Ill post up some pics.


___________________________________________________________________

Hahn Stage II - Mitsu TD06-20g |3" Turbo-back Exhaust | 61mm Bored TB |
HP Tuners | Innovate WB02 | Spec Stage 3 | Team Green LSD | TurboTech Upper | Full Addco Sways | Sportlines & Yellows |
Re: How To: LD9/Ecotec Boosted PCV System
Tuesday, February 03, 2009 1:08 PM
SweetnessGT
Mr.Choo wrote:I am still confused on this. If anybody can make up a diagram of a s/c eco, that would make a world of difference. I do, however, understand most of the concepts


As stated this does not apply to a S/C eco. The PCV system is cast into the lower intake manifold, the stock M61 setup by GM is fine... just toss a catch can onto the valve cover vent/inlet.

BlackEco - you could possibly do that but I'd rather use a unit that I know isn't going to just foul up with oil and heat, as well as fail under boost. Also, most PCV valves stock are 1/2" and I'm using 1/4" line.

Vince - Thanks for the clarification on the part #... sorry I got that wrong folks. You know I want 2 of those valves tho. lol

Jmarks/Brandon... I think a few bungs on the timing chain cover for relief would be a great idea, run it to a catch can just like the honda boys do. It would provide a lot of relief if you're running really high boost (like we are) and are starting to experience heavy blow-by. Let me know where you think you'd put those bungs...

-Chris-



-Sweetness-
-Turbocharged-
Slowly but surely may some day win this race...
Re: How To: LD9/Ecotec Boosted PCV System
Tuesday, February 03, 2009 1:25 PM
jmarks82
Would you want to put them closer to the timing chain cover? I think the cam towers and timing housing are connected right? I may just weld the bungs on this year while the motor is out...







Re: How To: LD9/Ecotec Boosted PCV System
Tuesday, February 03, 2009 1:41 PM
SLRdohc
good read. But does this concern everyone doing a boosted eco or ones who are just keeping the stock manifold.? just to clear it up


ECOtec DOHC


Re: How To: LD9/Ecotec Boosted PCV System
Tuesday, February 03, 2009 1:42 PM
David Ingram
Very nice Chris, I like this Idea. I think im going to just let my pcv hole in the head breath on its own for right now(since that solved my oil loss problems) and see how it does on dyno runs here soon. But this is definately something I want to do in the future.










~2014 New Z under the knife, same heart different body~
______________________
WHITECAVY no more
2012 numbers - 4SPD AUTOMATIC!!
328 HP
306 TQ
Re: How To: LD9/Ecotec Boosted PCV System
Tuesday, February 03, 2009 1:50 PM
SweetnessGT
Paul - this concerns LD9's and Ecos that boost with the stock intake manifold or an H.O manifold on an LD9. As stated, STOCK BOOST (i.e the M62 GMSC on the Ecotec and the M45 GMSC on the LD9) are FINE the way they are setup, they just need a catch can on the PCV inlet. (The green part of my diagram)

David - the PCV system is supposed to be under vaccum.... crank case air should be drawn out while clean air is drawn in.

-Chris-



-Sweetness-
-Turbocharged-
Slowly but surely may some day win this race...
Re: How To: LD9/Ecotec Boosted PCV System
Tuesday, February 03, 2009 2:13 PM
icemike89
What catch can is everoyne using? Im thinking of picking up a bwoody one and their not too far from me so maybe I could pick it up and check them out


Re: How To: LD9/Ecotec Boosted PCV System
Tuesday, February 03, 2009 2:15 PM
LAFNGAS
vince you know im in just let me know when to send ya the money




Forum Post / Reply
You must log in before you can post or reply to messages.

 

Start New Topic Advanced Search

Copyright © 1999 - 2024 GM Enthusiast Network
GM Enthusiast Network is not affiliated with the General Motors Corporation