werthie Posted December 30, 2013 Share Posted December 30, 2013 greetings from sunny So Cal . . . you may remember that i had a pretty bad engine fire back in April . . . many of you provided me with much-needed parts and assistance, for which i'm very grateful . . . THANK YOU!! . . . a buddy and i took everything apart and have been slowly putting it back together. we're now 95% done (the wiring took a while!), and we're down to the details. on the passenger side of the block, at the rear near the bell housing, there's a breather of some kind . . . please see the pictures below . . . what does this do? if the part coming out of the Motorcraft grommet is a PCV valve, i'm not getting any vacuum (suction) . . . if a hose fits over that part, where does that hose go? is this part of the smog system? if so, i'll need to get it working in order to register the car. any and all advice will be greatly appreciated! alan in LA Link to comment Share on other sites More sharing options...
xcarguy Posted December 30, 2013 Share Posted December 30, 2013 Alan, Congrats on the progress! From what I can see, it looks great! As for the part, it looks to be a PCV. This valve should (on most applications) have a hose running from the valve to a 'source' of vacuum, such as a vacuum port on a carburetor. As the car is running, the air being ingested into the engine via the carburetor will create a source of vacuum for crankcase ventilation. Post some full sized pics of your progress. :cheers: Link to comment Share on other sites More sharing options...
werthie Posted December 30, 2013 Author Share Posted December 30, 2013 hi shane . . . thanks for the response . . . i've looked everywhere for a source of vacuum, but i can't find anything. . . there must have been a hose on this breather before the fire . . . it may have gone to one of the K&N air filters, but that's where the fire started, so those were destroyed . . . the new K&N's have no fitting on the back plate . . . what am I missing? I REALLY don't want to drill any holes in my intake manifold. where's vacuum? :banghead: as for pics of the "resurrection," I was going to post a full history from burned-out hulk to finished product . . . but here's a shot of the engine compartment: Link to comment Share on other sites More sharing options...
escondidoron Posted December 30, 2013 Share Posted December 30, 2013 Here's a picture of an S3 SS Lotus Twin Cam circa 1969 of '70 that I found on the Lotus Seven Register site: http://www.lotus7register.co.uk/images/l7s3pix/SS4.jpg Note the hose below the rear carburetor in the picture. The one connected to the metal tube near the engine block and the bottom right hand corner of the air cleaner. It is the PCV line. By connecting the PCV valve outlet to the air cleaner (ported into the "clean" air side of the filter) you have found your source of vacuum. You don't want to connect to the intake manifold proper for a vacuum source for PCV as that would be downstream of the carb butterflies and would thus cause your fuel/air mixture to be lean on whichever cylinder (or cylinders) you tapped into. Link to comment Share on other sites More sharing options...
xcarguy Posted December 30, 2013 Share Posted December 30, 2013 Alan, plbs1234 on this forum is running a 1700 Super Sprint. You might send him a pm regarding his setup. Link to comment Share on other sites More sharing options...
The Stig Posted December 30, 2013 Share Posted December 30, 2013 This is simply the breather from the crankcase, nothing else. The best method is to have this connected by a pipe to a catch tank or back into the rocker cover. Many Crossflow cars have a pipe running down the side of the bell housing so it breathes onto the road. Not appropriate really and especially not if you want to use the car on track or pass any smog inspection. If a dry-sumped car, it would generally breathe back into the rocker. For neatness, you can replace the PCV valve (unless CA enforces using it) with a simple alloy union that pushes into the block - http://www.burtonpower.com/parts-by-fitment-type/parts-by-engine-ford/ford-cross-flow-kent/breather-elbow-x-flow-711m-23-5mm-fp280a.html. Does not use the bolt to locate it and provides a nicer look. There may of course be further requirements in CA for a fully closed system, hence the rocker cover option. Link to comment Share on other sites More sharing options...
rotus8guy Posted January 5, 2014 Share Posted January 5, 2014 Alan, Yes that's a PCV valve, and my understanding (I'm not in CA) is that they must be hooked up in California. Your best bet is to talk to someone in CA with a crossflow, but the hookup is simple. A hose from that valve runs to the intake manifold (vacuum source). Connecting it to the rocker cover would be the same as just capping it, connecting crankcase pressure to crankcase pressure. The purpose of the valve is to keep the mixture from being too lean, they are calibrated to the specific application. Don't take my word, Google is your friend HTH, John Link to comment Share on other sites More sharing options...
rnr Posted January 5, 2014 Share Posted January 5, 2014 my understanding (I'm not in CA) is that they must be hooked up in California. Sevens are smog exempt in CA. Originals are too old and SB100 kit cars have a lifetime exemption Link to comment Share on other sites More sharing options...
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