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Crankcase Breather for PCV system on Weber

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Hi, I have an EA81 that I'm currently swapping a Weber 32/36 into.  I traded for a used weber 32/36 and rebuilt it.  I'm currently waiting for PB blaster to soak into two of the studs that wouldn't initially come out(they are near the water inlet...).  Anyways I was looking at my PCV set up and was wondering if I could use a crankcase breather instead of tapping into the air filter box.  Would this work correctly?  I would have the passenger side crankcase going directly to the air filter box for fresh air.  I would then have the drivers side crankcase connected to the PCV valve and the original "F" coupler.  The smaller hose coming off the "F" coupler will then attach to the crankcase breather similar to these ones: http://www.oreillyauto.com/site/c/detail/SPT0/3991/N0572.oap?ck=Search_N0572_-1_4595&pt=N0572&ppt=C0088

 

I have taken a lot of pictures through the process, so hopefully after I get this all worked out I can post an interesting animated GIF of the vacuum pieces being removed...  Would appreciate any help with this and will post the results.  Thanks!

That is exactly how I have my EA81 setup.

 

Works great.

 

 

  • Author

I ended up just tying into the line connected to the filter box for now.  If I happen to get any oil I'm going to separate it from the system with the crankcase breather.  Thanks for the input guys!  Here's the way I ended up connecting the system:

 

2v1lpuw.jpg

 

I'll post the build pictures later.  I just finally had a chance to start it after it got dark.  It ran pretty damn well for the carb being set at baseline.  I also haven't had a chance to touch the timing yet.  One thing is the big inline filter I replaced the vapor filter with didn't seem to fill completely with fuel...  It almost seemed like it was starving the carb a bit.  This isn't the subaru style filter, and is more like a normal inline filter, just bigger.  Maybe if I aligned it vertically that might change things...  We'll see once I get some light in the morning.

I've got my passenger side pcv hose running to the air filter box and the drivers side running straight to the valve. Seems to work just fine and it's simpler than the setup you've got.

  • Author

I thought the driver's side crankcase still needed a source for fresh air along with the pcv, but if you aren't having any problems seems like it works well.  Here's an interesting animated gif of the build.  Would have been better if I would have taken care to shoot from the same angle every time... oh well

 

output_gqhGwN.gif

  • 2 weeks later...

I've had the 32/36 on my EA81. Now going to a 38/38 and need to route the ventilation.

 

The passenger side (US) should get clean filtered air that is drawn into the engine. You can get one of those small filters or tap into the air filter box for this but it should not be connected to any other  part of the ventilation system.

 

The drivers side goes to the PCV but along that hose if a fitting you describe. This fitting should have a smaller hose off it and ideally this hose should go to the intake near the carbie's throat. It allows for excess fumes that the PCV cannot cope with in short bursts and is smaller for a reason so fumes favor the PCV. Thats my understanding of the system.

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