hatchsub Posted May 26, 2009 Share Posted May 26, 2009 Im pretty sure that my PCV system is responsible for my blue smoke sometimes. I have a weber carb and therefore have my pcv set up like this; Both valve covers are connected by a hose. There is a t-fitting that goes down to the pcv. Off of that line there is another T-fitting that shoots up to the weber air cleaner. Would it do any harm and would it help if i just put mini breathers on both valve covers and left the PCV going straight up to the air cleaner? Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted May 26, 2009 Share Posted May 26, 2009 It would do a lot of harm - but not much *more* harm than your current system which is not doing the job either. The goal is to remove blow-by gasses from the crankcase - in the old days this was done with a road draft tube, but that became unacceptable with the environmental movement. The PCV system needs a directional flow - in one head and out the other then to the PCV valve. But you need a smaller diameter hose between the second head and the PCV valve going back to the air filter in order to break the high vacuum and prevent oil being sucked into the manifold. GD Quote Link to comment Share on other sites More sharing options...
Loyale 2.7 Turbo Posted May 26, 2009 Share Posted May 26, 2009 Im pretty sure that my PCV system is responsible for my blue smoke sometimes ... I Have some Pictures about that Setup and how I did Fix that, in my "Weber Swap" Writeup... if you want to see `em and How I Fixed that, Just Click on my Avatar and you`ll Reach a List of my Writeups. Kind Regards. Quote Link to comment Share on other sites More sharing options...
Spiffy Posted May 26, 2009 Share Posted May 26, 2009 I have the same setup as you and haven't had any blue smoke... I took the 2 stock hoses that went to the subaru air filter and hooked them to the weber air filter... the driver's side already had the pcv line hooked into it... I simply made a T from pipe fittings at home depot and hooked them into the supplied weber air filter spot... since this is the same setup as stock I don't understand how it could be wrong... the stock system had both valve cover hoses going to the air cleaner, one on each side... maybe mine is ok because of the different diameter hoses... no idea... Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted May 27, 2009 Share Posted May 27, 2009 since this is the same setup as stock I don't understand how it could be wrong... the stock system had both valve cover hoses going to the air cleaner, one on each side... maybe mine is ok because of the different diameter hoses... no idea... It is not the same as stock if you don't have the exact same diameter hoses as stock. When you are talking about flow rates and directions, hose diameter plays a huge role. Often in vacuum systems you have to carefully "tune" the system by use of very accurate "orifices" that are inserted to restrict flow rates at certain points. I have explained how the system works in other threads and it's tireing to do it over and over. Do a search for "PCV" and my user name and I'm sure you'll find it. GD Quote Link to comment Share on other sites More sharing options...
Spiffy Posted May 27, 2009 Share Posted May 27, 2009 It is not the same as stock if you don't have the exact same diameter hoses as stock. When you are talking about flow rates and directions, hose diameter plays a huge role. that makes sense... and I did reduce the 5/8 and 5/16 hoses into a single 1/2 so that's got to be messing up the flow a bit... I guess the best thing to do would be to have 2 holes in the weber air filter the same size as the stock hoses and get rid of the reduction T... time for another trip to home depot... hehe... Quote Link to comment Share on other sites More sharing options...
Flowmastered87GL Posted May 27, 2009 Share Posted May 27, 2009 I ran just bulk hose on my GL... never smoked I had a genuine subaru PCV valve also.... do you have one or just a fram cheap-o??? Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted May 28, 2009 Share Posted May 28, 2009 that makes sense... and I did reduce the 5/8 and 5/16 hoses into a single 1/2 so that's got to be messing up the flow a bit... I guess the best thing to do would be to have 2 holes in the weber air filter the same size as the stock hoses and get rid of the reduction T... That is not the way the system works. You need ONE port on the filter. From there you T into two 5/8" hoses - one goes to the passenger side head. The other reduces to 1/4" ID then back to 5/8" and T's into the line from the drivers side head to the PCV valve. The key to making it work is the reduction to 1/4" ID to give an orificed vacuum break on the PCV line. Otherwise it will have too much suction and will pull oil out of the driver's side head. GD Quote Link to comment Share on other sites More sharing options...
hatchsub Posted May 29, 2009 Author Share Posted May 29, 2009 That is not the way the system works. You need ONE port on the filter. From there you T into two 5/8" hoses - one goes to the passenger side head. The other reduces to 1/4" ID then back to 5/8" and T's into the line from the drivers side head to the PCV valve. The key to making it work is the reduction to 1/4" ID to give an orificed vacuum break on the PCV line. Otherwise it will have too much suction and will pull oil out of the driver's side head. GD Im trying to picture that. Do you happen to have a picture of that setup? Also to answer the other question im running a genuine subaru pcv valve. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted May 29, 2009 Share Posted May 29, 2009 Ok - I got you pictures - so all you people that are running your PCV wrong GO FIX IT! I'm tired of trying to explain it anyhow... Overview of the system: This shows the "special" EA71 (gen 1, round air filter type) hose and special T fitting that makes this setup easy and clean - if you can find one. I suppose there are part numbers associated with them and you could order a set - I don't have any extra so don't ask! The blue T-fitting from the filter is from an EA82 SPFI. Hey look..... I guess I do recycle! And here's another angle: Re-read my last post and then look at these pictures. I'm sure it will make sense to you if you stare at it for a while. Any questions? GD Quote Link to comment Share on other sites More sharing options...
Dirk Posted February 27, 2010 Share Posted February 27, 2010 Hey, The search system won't let me search for PCV. How do I get around this? Quote Link to comment Share on other sites More sharing options...
hatchsub Posted February 27, 2010 Author Share Posted February 27, 2010 Im not sure but i usually get around it by searching for something else like -hose routing -vacuum -weber breather typing vacuum in got me this thread again. I kno there is probably a way around the search feature but i havent figure it out or if it was said i forgot. Quote Link to comment Share on other sites More sharing options...
Dirk Posted February 27, 2010 Share Posted February 27, 2010 Sweet. Thanks. This is the system that my car came with. It appears to be far more simple than the systems being talked about here. I wonder what the draw backs are of this simpler system. Will it clog the carb? Quote Link to comment Share on other sites More sharing options...
Dirk Posted February 27, 2010 Share Posted February 27, 2010 This is the "system" I am currently using. This is actually legal in New Zealand! So much for being a 'green' country! Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted February 27, 2010 Share Posted February 27, 2010 The drawback is that you don't have a PCV valve in the manifold so any oil that gets sucked into the system ends up in the carb and air filter instead. Plus it's probably not as effective for removing crankcase gasses since the two pipes are fighting each other and trying to suck on both sides of the engine. With the PCV setup as talked about in this thread you have an IN and an OUT side of the engine creating a positive flow from one side to the other. With the hose going into the soda can you have NO flow - so that's completely innefective. You might as well just leave the valve cover port open...... GD Quote Link to comment Share on other sites More sharing options...
WRX2FFU Posted February 27, 2010 Share Posted February 27, 2010 Kinda un related but.... Unless your pulling oil into the carb your blue smoke is most likley ring issues. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted February 27, 2010 Share Posted February 27, 2010 Kinda un related but.... Unless your pulling oil into the carb your blue smoke is most likley ring issues. Probably not - valve stem seals is much more likely on Subaru's. GD Quote Link to comment Share on other sites More sharing options...
Dirk Posted February 27, 2010 Share Posted February 27, 2010 With the hose going into the soda can you have NO flow - so that's completely innefective. You might as well just leave the valve cover port open...... GD Aye, I know that. The cans are just catching the crap that comes out of the hoses. The stock air filter box was always a bit gunky. Think I might salvage a PCV system from a wreck and bang in on. Quote Link to comment Share on other sites More sharing options...
Dirk Posted February 27, 2010 Share Posted February 27, 2010 Just been looking it up. I guess I'm gona have to replace the whole manifold then. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted February 27, 2010 Share Posted February 27, 2010 Why not just drill and tap your existing manifold or adapt a PCV valve that's designed to go inline with the hose and simply T it into the brake booster? GD Quote Link to comment Share on other sites More sharing options...
Dirk Posted February 27, 2010 Share Posted February 27, 2010 Errr. Cool. thats what I'll do. Thanks man. Quote Link to comment Share on other sites More sharing options...
eulogious Posted February 27, 2010 Share Posted February 27, 2010 Hey, The search system won't let me search for PCV. How do I get around this? The easiest way I found is using a '*' at the end of the word, so to search for 'PVC' you would search for 'PVC*' This has always worked for me! Just thought I would throw that tip in there... Quote Link to comment Share on other sites More sharing options...
spikedbeetle Posted February 27, 2010 Share Posted February 27, 2010 Would it do any harm and would it help if i just put mini breathers on both valve covers and left the PCV going straight up to the air cleaner? This is almost exactly what I did. I put two mini breathers on and got rid of the PCV all together. It would do a lot of harm. GD I do have an air cleaner base that I am currently not using for one of my carbs on my dual carb setup that has a line for a crank case breather. Do you think it work work well if I left a mini breather on one valve cover and ran a line from the other valve cover through an inline PCV and then into the air cleaner? Would that create the through cross flow that the engine needs to work properly? Here is how it sits now. Quote Link to comment Share on other sites More sharing options...
Gloyale Posted February 28, 2010 Share Posted February 28, 2010 Do you think it work work well if I left a mini breather on one valve cover and ran a line from the other valve cover through an inline PCV and then into the air cleaner? Would that create the through cross flow that the engine needs to work properly? ONe side "open" w/ breater. Other side hooked into a PCV valve installed in Manifold, or "T''d into brake booster vac line. Point being in the end.....the only reason the air filter box is part of the PCV....is to filter air before going into the one side breater.....if you have a seperate filter on there, then the other vavle cover port get's hooked straight to the valve. No further need to tie it into the air box. Quote Link to comment Share on other sites More sharing options...
naru Posted February 28, 2010 Share Posted February 28, 2010 ONe side "open" w/ breater. Other side hooked into a PCV valve installed in Manifold, or "T''d into brake booster vac line. Point being in the end.....the only reason the air filter box is part of the PCV....is to filter air before going into the one side breater.....if you have a seperate filter on there, then the other vavle cover port get's hooked straight to the valve. No further need to tie it into the air box. Not completely true. At wide throttle openings(low manifold vacuum,high blowby),PCV is unable to handle the flow and blowby gases are routed to the carb intake. Quote Link to comment Share on other sites More sharing options...
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