Want to clarify PCV plumbing...

jsteele22 · #1 07-10-2007, 01:10 PM

Hi,

I bought an EG33 from a wrecker and I'm getting ready to re-assemble it. It came with intake manifold and throttle body, but nothing further upstream. And of course my notes from way back when I disassembled it are inadequate. I'm trying to figure out how to hook up the PCV system and have a few questions.

1) the hoses from the cam cover breathers - can they simply be plumbed into the air intake somewhere before the throttle body ? (I'm not using the stock intake, gonna fab something up.)

2) The only port I see in/out of the crankcase is the roughly 1/2" one at the passenger side rear, connecting into the oil/air separator. This makes sense for an output, but I don't see a seperate port where fresh air would be input into the case. Is there a seperate fresh air input port somewhere I'm missing, or does one port do both ?

3) In the parts diagram at subaruparts.com, there is a part (#11821) called "Connector-purge control valve". I can't find this part in my pile, and I don't quite get what it does : is it simply a connector, or is also a valve ?

4) Is this part the answer to question (2) ? Does it take fresh air from one hose and let it flow into the crankcase, and then direct dirty air coming out of the crankcase through the other hose into the PCV valve ? It looks as if it fits onto the port at the passenger side rear of the crankcase, but it's kinda hard to tell from the drawing.

Thanks for any help you can provide,

Jeff

jsteele22 · #2 07-12-2007, 11:07 PM

bump .... any info appreciated

I think I've got it figured out, but can someone at least tell me which hose in the picture connects to the PCV valve ? Is it H415082 ? It sorta looks that way in the pic, but then again, it sorta doesn't.

Thx

dannmarr · #3 07-13-2007, 03:58 AM

The diagram is tricky, but you are correct.

jsteele22 · #4 07-13-2007, 12:31 PM

Quote:

Originally Posted by dannmarr

The diagram is tricky, but you are correct.

Great, thanks.

Yeah, actually if I stare at it long enough, I can now "see" that the hose is indeed bent at the end and points in the right direction. Somehow I missed that the first 23 times...

Our warm and fragile planet thanks you....

jsteele22 · #5 07-25-2007, 02:22 PM

Can someone help ? I'm still confused

I ordered new parts for the PCV system. In particular, the one I asked about before (11821, aka the "F" connector) is not a valve at all, simply a 3-way connector. So my big question is :

1) where does the top port of this F connector (hose H412172) go ?

I had thought that it went to the intake system, after the air filter but before the throttle plate. But this would create a substantial path for air to flow from the air filter through the "F" connector to the PCV valve, creating a huge vacuum leak/ high idle. No ?

Also, I've been reading up on PCV systems generally, and they all seem to have an inlet for fresh air that is distinct from the outlet to the PCV valve. My second question :

2) In our case, is the fresh air inlet via the breathers on the cylinder heads ? (If not, where is it ?)

Thanks,

Jeff

SVX33 · #6 07-26-2007, 10:44 AM

Quote:

Originally Posted by jsteele22

Can someone help ? I'm still confused

I ordered new parts for the PCV system. In particular, the one I asked about before (11821, aka the "F" connector) is not a valve at all, simply a 3-way connector. So my big question is :

1) where does the top port of this F connector (hose H412172) go ?

I had thought that it went to the intake system, after the air filter but before the throttle plate. But this would create a substantial path for air to flow from the air filter through the "F" connector to the PCV valve, creating a huge vacuum leak/ high idle. No ?

Also, I've been reading up on PCV systems generally, and they all seem to have an inlet for fresh air that is distinct from the outlet to the PCV valve. My second question :

2) In our case, is the fresh air inlet via the breathers on the cylinder heads ? (If not, where is it ?)

Thanks,

Jeff

Fortunately I just had all of that apart. The top connection on the F connects to the bottom of the intake hose before the throttlebody, or more precisely to the chamber at the throttlebody connection where all the oil from blowby collects.
John