Hey,

 

so my car has started using about a quart of oil a week, and today it belched out an enormous cloud of smoke when I was on a right hand cloverleaf. both of these seem to be signs of a problem in the pcv system.

 

I will be eliminating the ties to the air box when I check into it tomorrow. Ill just run a breather cap on the passenger side and the hose from the drivers side to the valve.

 

My question though is what is the simplest way to vent the gasses? I dont have to go through emmisions, so would it hurt the system to run breather caps on both passenger and drivers sides? is the connection to the manifold important for the system or the running of the car? On the surface i wouldnt think it would change anything, just eliminate another possible failing part (though that breather cap on the drivers side might get dirty super fast). Not that I get any satisfaction from polluting, but my goal with this car is to run it as simple as possible.

Why go through all that work? The PCV system works perfectly fine when it's working, and it's not hard to fix. It's a very simple system. Start by replacing the PCV valve. Get a can of brake cleaner, take all the PCV hoses off and clean them out.

It's probably just clogged up with gunk.

get the pcv reroute kit to cure the oil smoke on right turns. its 2 plastic tee fittings and a plug that replace the t and the elbow on the airbox.

 

and buy a subaru pcv valve. aftermarket never solves the problem, maybe makes it worse.

 

don't delete the valve. period. the pcv valve allows vacuum to be pulled on the crankcase, slightly aiding ring seal.

I ended up cleaning out the old pcv valve and putting it back in. I only replaced it since I just bought the car and was replacing the stuff nobody pays attention too.

 

I ran a new 5/8 line in large arc by the air cleaner and down, hopping a bit more height will help.

 

I ordered a subaru pcv from the dealer, it will take a couple of days to get here. does the elbow fitting actually help in someway besides the shape of the plumbing? I have a normal 5/8 elbow for pcv i can put on if it actually does something.

there was a service bulletin for this, my '87 would make James Bond proud on a right hand turn, under compression coming in hot on my last corner to the house. my '90 never did it

 

GD had a really good description of the fittings, diameters etc to make a 'correct' system

 

see if search yields anything here, it's a known issue (which click and clack misdiagnosed on Car Talk)

Phil (kingbobdole on here and other Subaru forums) deleted his with the valve cover breather set up and had issues. I'm not sure what the issues were but i think it was simply puking oil out the valve cover breathers.

The PCV is there to eliminate corrosive blow-by gasses from contaminating and acidifying your oil.

 

You need POSITIVE flow. Clean air going into one vavle cover, through the crankcase, and out the other. For that you need either pressure or suction. The intake has suction..... thus the PCV valve.

 

Eliminate it at your own risk.

 

Pretty silly and ignorant thing to do IMO.

 

GD

yah, once I looked into it the valve is a good thing. dual breathers would keep the pressure from building, but not remove the posibly harmfull gasses as well.

 

GD - someone mentioned you writing up a proper routing for pcv, but I havent found it. I will have a breather on the passenger side, 5/8 pcv hose out of the drivers side running to a OEM Subaru valve (once it gets here). Someone mentioned using a T or angle fitting, which I will eventually do just to cleanup the routing, but is it essential? My friend said his had a lot less suction with the angle connecting the 2 hoses.

 

What would you suggest for the simplest setup for pcv?

I Agree with GD, your engine Needs the PCV.

 

I Have a Photo Diagram, is for the Carbed EA82's but Might Help, also an Oil Catch can as the one I Placed between the Divers side hose and the PCV to catch the blow by oil.

 

See ~► Here.

 

Kind Regards.

Never EVER delete the PCV system. It's sucking through a lot of oil because you have poor cylinder compression and it's causing blowby, pressurizing your crankcase. If you don't have it ventilated, you'll start blowing seals.

 

There are some alternatives, such as a pan evac system, where instead of piping into your intake, it dumps into your exhaust. However this isn't usually legal and is mostly common on drag cars. Another option would be to use an electrical vacuum pump, but most pumps don't have enough volume to keep up.

 

So do what everyone else does: get an oil catch can. They are specifically designed to catch excess oil coming through the PCV system. You can find some on eBay, or make one out of mayonnaise jar, or do what I did and get an air filterer for an air compressor from harbor frieght for ten bucks.

I wasnt talking about deleting the crank case ventilation, I was talking about running dual breathers like people sometimes do on old V8's. this would delete the pcv valve, and just vent to the atmosphere. with research the vacuum does help remove some possibly harmful vapors though so I kept it.

 

seems to be largely fixed now, routed some new 5/8 hose up by the air box with a new elbow, cleaned the pcv valve, and installed a breather to eliminate the hoses to the airbox. seems to be working much better, ill install a new subaru direct pcv once it gets in at the dealer just in case.

Even just putting breathers on isn't very good. Needs to be pulling some negative pressure. I've always been tempted to make a pan evac setup with a catch can just to get more pressure.

From what I hear lots of race setups run air pumps to pull those gases into the exhaust so they are vacuated but not messing with the combustion process. If I wanted a fancy setup I would look into hooking the system up to the ASV pump. No idea of the dangers of unburned fuel/water/oil in the exhaust, just an initial impression. Im assuming it would not play nice with a cat, but race motors wont run that anyway.

 

I just want the car to stop sucking up oil, and I dont want anything in the tailpipe causing afterfires either. If thats your thing though maybe that can work for you.

Was looking at the crankcase evac kits on ebay, pretty straight forward. Thinking I might try and weld a venturi tube into my exhaust, prolly just past my cat, and run it through a catch can to my PCV lines.

 

What could possibly go wrong?