Convert crankcase breather tube to PVC system
 

I want to install / use a PVC system instead of just directing the crankcase ventilation through the rubber breather tube at rear of engine down to the road as it gets the chassis and even the motor compartment oily over time? Can I put a PVC valve on that tube and run to a vacuum intake on manifold? The oil filler tube has a breather cap so the vacuum should pull air through the engine and through the PVC to the vacuum intake to be re burned as in more modern setups right?

Re: Convert crankcase breather tube to PVC system
 

You got an 8BA in there ain't you? I'm guessing the rubber hose you talk of is shoved on the end of the steel road draught tube?
Any how, yes you can fit a PCV in there or as has been done on many an 8BA. Pull the road draught tube out of the manifold and fit the PCV right there. Obviously you need to fit something like a core plug in the hole then drill a hole in that and fit the PCV with a grommet.
The air will come in the oil fill tube, through the engine and then through the old road draft tube/PCV. As you stated.
Martin,
Draft or draught?

Re: Convert crankcase breather tube to PVC system
 

There have been a number of threads in the past on PCV setups.

Re: Convert crankcase breather tube to PVC system
 

Draft

Re: Convert crankcase breather tube to PVC system
 

Thank you.
Martin.

Re: Convert crankcase breather tube to PVC system
 

I want to use the vacuum port on my center carb and connect to draft tube. do I even need a PVC valve? ( 94nwith vac. port for timing is plugged as using an electronic dist. ). with constant vacuum wouldn't it just stay open? Or do I need the extra vacuum resistance to prevent too much vacuum loss so the engine runs smooth?

Re: Convert crankcase breather tube to PVC system
 

The PCV valve prevents catastrophic engine damage should a backfire ignite gasses in the crankcase. Install a valve. And it should be routed directly to the intake vacuum, not any timed vacuum port on the carburetor.

Re: Convert crankcase breather tube to PVC system
 

The PCV valve has a spring and pintle system combined with an orifice that regulates the flow depending on the vacuum applied.

Re: Convert crankcase breather tube to PVC system
 

Here's an item you might want to consider:
Flathead V-8 Parts : 49-53 FORD FLATHEAD PCV VALVE KIT

See it at this link:
http://jamcosuspension.com/products/...productID/1504

Re: Convert crankcase breather tube to PVC system
 

Thx for the heads up on keeping the PVC in the circuit for the backfire potential. Just went with the rational that most newer vehicles with PVC set up run into the air cleaner using the vacuum the carb creates while pulling air inside air cleaner? Thought it was more or less the same. Rethinking it would probably muck up the carb.
So there is what looks like a 3/8- 16 coarse threaded hole on driver side near the center of the Edelbrock mfld. that came with engine. Looks like a cut off 5/8" head bolt threaded into it. ( looks homemade ). Thought it would be a pipe thread but is a standard thread with Teflon Tape on it? Will modify and use for PVC circuit. I removed the bolt / plug while engine was running and it was enough vacuum loss to stall the engine (expected ). When I hook the draft tube and PVC into the circuit will it provide enough vacuum resistance to allow engine to run right?

Re: Convert crankcase breather tube to PVC system
 

The air cleaner is the source for filtered fresh air that is pulled into the engine, then exiting through the pcv, with manifold vacuum.

Re: Convert crankcase breather tube to PVC system
 

Thx flatjack9, I will be using the 3/8 threaded hole on the manifold as the vacuum source.

Re: Convert crankcase breather tube to PVC system
 

As V8 Bob stated, the PCV system that has a hose going to the air cleaner uses the air cleaner to pull filtered air INTO the engine, air comes in here goes into the crankcase (usually useing the valve cover on one side) through the crankcase, out of the other valve cover, through the PCV and lastly into the intake manifold.
The vacuum port on the edelbrock intake, you say it's in the center, but does it connect to both sides of the manifold? These manifolds feed the two center ports on one side and two outer ports on the other through one side of the carb, other side of the carb is routed to the other four cylinders. If you feed your PCV into only one half of the manifold, you'll have four cylinders running leaner than the other four. Not good. The PCV needs to be "seen" by both sides.
Martin.