Lacyjs9 Posted June 16, 2013 Share Posted June 16, 2013 i have been thinking since i done my weber swap about the baffels and hose to the anti suction valve that i capped off. how about crank case vent filters anyone ever considered/tried i know those hoses ran to the old air box Link to comment Share on other sites More sharing options...
mikaleda Posted June 16, 2013 Share Posted June 16, 2013 Don't block the PVC system off, it will cause a buildup of pressure in the engine and cause increased engine wear. PVC has been around since the 60's there's a reason for it. Link to comment Share on other sites More sharing options...
Loyale 2.7 Turbo Posted June 16, 2013 Share Posted June 16, 2013 (edited) Yes, your engine NEEDS the Positive Crankcase Ventilation System, there's No other way to avoid the internal pressure buildup as Mikaleda wrote, but also there's no other way to suck out the harmful corrosive vapors that combustion pours onto the crankcase chamber: By the PCV system, they goes to the intake manifold to be burned on the Cylinders via the PCV's Valve. As I suggested before, read this Writeup to find the PROPER routing for the PCV system on (weberized) EA engines: ~► http://www.ultimatesubaru.org/forum/topic/71510-ideas-on-swaping-a-weber-carb-on-ea82%C2%B4s/ It is on the last posts. Kind Regards. Edited June 16, 2013 by Loyale 2.7 Turbo 1 Link to comment Share on other sites More sharing options...
Lacyjs9 Posted June 16, 2013 Author Share Posted June 16, 2013 i have the driver side vent pipe on top of the valve cover ran to the pcv valve and the pass side to the carb im talking about the ones on the bottom the ones we discussed in my other post Link to comment Share on other sites More sharing options...
Lacyjs9 Posted June 16, 2013 Author Share Posted June 16, 2013 (edited) that charcoal filter and pipe run to the bottom of the crank case and ran into the old air box Edited June 16, 2013 by Lacyjs9 Link to comment Share on other sites More sharing options...
djellum Posted June 17, 2013 Share Posted June 17, 2013 theres 2 things to consider, pressure and gasses. breathers will do fine to relieve pressure, but the gasses in the crankcase need to be removed as well, which wont happen with the dual caps. if you look at lots of race cars they run pumps that take care of the crankcase gasses without feeding them to the motor. I thought about the same thing and just hooking up the ASV system to pull the gasses out. Id imagine that it would work, but the problem would then be lots of dirty (and possibly flammable) gasses going through your cat and muffler. also with the amount of oil that can get sucked out of the head on right hand turns you would likely end up with oil in your exhaust making a smelly mess. theres also the fact that the ASV's arent tuned for that, and wont provide proper suction, though I dont know if it will be less or too much. Link to comment Share on other sites More sharing options...
Lacyjs9 Posted June 17, 2013 Author Share Posted June 17, 2013 theres 2 things to consider, pressure and gasses. breathers will do fine to relieve pressure, but the gasses in the crankcase need to be removed as well, which wont happen with the dual caps. if you look at lots of race cars they run pumps that take care of the crankcase gasses without feeding them to the motor. I thought about the same thing and just hooking up the ASV system to pull the gasses out. Id imagine that it would work, but the problem would then be lots of dirty (and possibly flammable) gasses going through your cat and muffler. also with the amount of oil that can get sucked out of the head on right hand turns you would likely end up with oil in your exhaust making a smelly mess. theres also the fact that the ASV's arent tuned for that, and wont provide proper suction, though I dont know if it will be less or too much. what do you mean by dual caps?? i dont want to put breathers on em where they come directly out i want to run some pipe straight up and put the breathers on the end of the pipe where they are sticking up i capped mine off im assuming they shouldn't be because they seem like they are vents to me Link to comment Share on other sites More sharing options...
djellum Posted June 17, 2013 Share Posted June 17, 2013 (edited) ok, we all thought you were talking about hooking your crank case vent ports to the ASV system. sure just use a vent cap or foam filter for the ASV input, that would activate the system again and keep contaminants out. sorry, ready too much into that one. I would personally leave it completely unhooked. it does nothing for helping it run, and I doubt its effectiveness even on an emisions side. Im not an expert on it, but I think there just diluting the contaminants with air to lower the readings. Edited June 17, 2013 by djellum Link to comment Share on other sites More sharing options...
the sucker king Posted June 17, 2013 Share Posted June 17, 2013 what do you mean by dual caps?? i dont want to put breathers on em where they come directly out i want to run some pipe straight up and put the breathers on the end of the pipe where they are sticking up i capped mine off im assuming they shouldn't be because they seem like they are vents to me You misunderstand what the ASV does. It mixes clean air into your exhaust to help oxidation of unburnt fuel in the exhaust. You can run yours up to your air cleaner or rig up a seperate filter them. Or leave them capped off. Be aware that the ASV makes a lot of noise without the silencers. Link to comment Share on other sites More sharing options...
Gloyale Posted June 17, 2013 Share Posted June 17, 2013 Unscrew the pipe were it feeds into the ASV, insert a quarter int he opening, tighten the pipe back off. Ditch all the plastic silencers. Done Link to comment Share on other sites More sharing options...
the sucker king Posted June 17, 2013 Share Posted June 17, 2013 Unscrew the pipe were it feeds into the ASV, insert a quarter int he opening, tighten the pipe back off. Ditch all the plastic silencers. Done The pipe does not feed the ASV. The pipe is the outlet. Link to comment Share on other sites More sharing options...
Lacyjs9 Posted June 17, 2013 Author Share Posted June 17, 2013 i understand everyone has theres capped off some way or another. what im getting at is why? when it was venting with the old air box? my haynes manual says the avs feeds in clean air and vents bad now theyre both closed off so whats the vent? the driver side crank case to the pvc valve? Link to comment Share on other sites More sharing options...
the sucker king Posted June 17, 2013 Share Posted June 17, 2013 The ASV and PCV are completely separate systems. The ASV does not vent anything . People will tell you to get rid of it because it robs power or is unnecessary. Whatever. I don't notice a difference in power and it does help your car run cleaner. The most valid reason to block or delete it in my opinion is when you do the weber conversion you no longer are using the air cleaner box that it hooks up to and it's a cleaner look. That said, it is also the one piece of emissions equipment my 1980 is required to have and I am choosing to keep it. Link to comment Share on other sites More sharing options...
the sucker king Posted June 17, 2013 Share Posted June 17, 2013 I should add that I think it is insignificant in the long run. Don't lose any sleep over it being hooked up or not Link to comment Share on other sites More sharing options...
djellum Posted June 18, 2013 Share Posted June 18, 2013 the air box was a common place for a lot of systems to coexist, but they are actually fully separate systems and the airbox kept them from connecting to each other. the ASV is simply an air pump that puts extra air into the exhaust. look up air injection on wiki or something, that is what it is. it took filtered air from the airbox and injected it into your exhaust manifold so that your catalytic would be fed both unburnt fuel and raw air so that it could do its thing. my suspicion since in the older times they only put them on california emissions cars is that it was simply diluting the reading at the tailpipe. the reason for deleting it is that if any part of it leaks, which its prone to do, then it becomes an exhaust leak. It was causing afterfires when I shifted due to leaky baffles. it wont hurt or help power, its neutral and only related to emissions. for most of us the reason we want these cars is simplicity and reliability, so for that sake we simply remove unneeded complication. the PCV system allows for 2 things, the release of pressure in the crankcase, and the removal of gasses that make it by your piston rings. those gasses can be corrosive and harmful to your engine long term (they are a big reason for your oil breaking down). having the heads open to the air will solve the pressure issue, but not the removal of gasses, thats why you have a PCV valve. the PCV will open to the manifold and the engine vacuum will pull out the gasses to burn them. The asv's mount to the exhaust manifold, right at the head, and then at the air box, but not to the PCV. the PCV will intake air at the top of the passenger side head and will need a breather cap. the air will travel through the motor and exit out the top of the drivers side head. that hose will go to the PCV valve on the back of the manifold under the carb. you will want an inline T fitting between the drivers head and the PCV valve. some people leave it open, and others hook it to the air cleaner. its just to reduce some of the suction so you dont pull raw oil into the manifold. 1 Link to comment Share on other sites More sharing options...
espey_16 Posted June 18, 2013 Share Posted June 18, 2013 "Thread jack" can someone post a pic of the pcv system for me please, I have no idea what it looks like, unless its the 2 hoses going to the valve covers. Link to comment Share on other sites More sharing options...
djellum Posted June 18, 2013 Share Posted June 18, 2013 Jezek linked a post earlier. 2 Link to comment Share on other sites More sharing options...
mikaleda Posted June 19, 2013 Share Posted June 19, 2013 A search should give you that Link to comment Share on other sites More sharing options...
Gloyale Posted June 20, 2013 Share Posted June 20, 2013 The pipe does not feed the ASV. The pipe is the outlet. You are correct. Reason to cap them is because when the reed valve goes bad then exhaust gas will flow out those pipes and sound like hell. You can always hear them mile away when they are bad. Blocking the big screw in fitting with a quarter works great. Old trick I learned here on the board Link to comment Share on other sites More sharing options...
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