pvc valve

There's been some discussion of this before. May not have been specifically for a 21 stud, but isn't it the same as a 59A? Kahuna may chime in, he made his by putting a cap on the rear fill hole with a tube off of it for the PCV that is plumbed into the bottom of the intake to suck from.

I'm working on an idea to cap the vent tube at the front of lifter valley and drill a hole in the side of it for the PCV to suck off of. It stands to reason that the vent on the side of the oil pan is no longer necessary and can be plugged. So, this way the rear filler/vent tube would still be operational with the crankcase gases being sucked from the front utilizing the PCV plumbed into the bottom of the manifold. Sorry, no pictures yet as I am just brainstorming so far.
 
"I'm working on an idea to cap the vent tube at the front of lifter valley and drill a hole in the side of it for the PCV to suck off of. It stands to reason that the vent on the side of the oil pan is no longer necessary and can be plugged. So, this way the rear filler/vent tube would still be operational with the crankcase gases being sucked from the front utilizing the PCV plumbed into the bottom of the manifold. Sorry, no pictures yet as I am just brainstorming so far."[/QUOTE]

This will work on an 8BA, where gases/fumes are pulled up from the crankcase into the front tube, then through the intake and and out the road draft pipe, but on the '35-'48 engines the front tube extends all the way down through the block to the pan vent, as the air flow is opposite. On these, air enters the rear breather, moves down into the crankcase, then up into the valve chamber, and down through the front vertical tube and out the pan vent. If you plug the pan vent, you will not have any flow.
I'm not sure what the best way is to add a PCV system on a pre-8BA engine, but pulling the fumes from the pan vent would at least keep the air flow as designed, and might be the easiest.
 
I theory you don't need at opening to the atmosphere since there will always be pressure build from even the slightest amount of blow by. In practice, they usually had a connection from the crankcase to the air filter housing so that there would be no underpressure or overpressure and the available air opening would be filtered. This practice only had problems when the blow by becomes greater than what the PCV system can draw back. It then begins to push an excessive amount of oily vapor into the filter causing it to start fowling the air filter housing with oil.

Kerby
 
Brendan:

Following up on what Kerby said, I once considered a PCV valve. But I found that effective PCV on my late-model 221 was to simply wrap air filter paper or fine air filter screen around the crankcase vent. Then use a PCV breather style oil-filler cap (similar to the old Chyrsler style PCV caps) with tubing to the low pressure side of the carb on the air filter. Since I use an electric fuel pump, I have a metal tube filled with SS mesh (too suppress oil fouling) sitting atop the manifold's oil filler/pump hole that feeds directly to the bottom of the 97's homemade pleated-paper air cleaner box. If you don't have the front crankcase vent, you can use the dipstick tube instead.

Jack E/NJ
 
i use the pcv because it stops the unpleasant odors from getting in the cab when the engine is idling, like when your in a parade
 
Ditto on PCV, ford1! Also like when you're sitting in a NJ traffic jam on a hot day in July!

Jack E/NJ
 
I think PCV is a major durability factor, reducing sludge and acid in there by removing water vapors and acids from combustion.
Ford way of installing PCV on early engines:
Close off the outlet on pan...factory PCV pans were stamped with this left closed. Weld on a cover for the hole.
Discard oil filler cap/inlet and replace with something with a modern paper element. Ford used a big oil bath, about half the size of carb one.
Vacuum was pulled from under carb via a plate with channels to both sides of intake OR from the big manifold plug meant for truck brake booster...this is a huge hole with 2 small passages to the sides of manifold. Vac line, a small one of I think 1/4" tubing, went to the right/passenger side of the part of manifold supporting the gen beacket, in a position directly above the internal breather stack.
 
Well, Roger, if you're talking about using an exhaust vacuum venturi tap, I'll support the idea. 8^)

Jack E/NJ
 
Unless I am missing something (entirely possible), Bruce's description seems to support my theory except I am thinking about hiding the valve under the intake manifold. Bruce's description also explain to me why Ford brought that internal breather tube right even with the top plane where the intake manifold sits. It looked to me like the top of that tube is effectively blocked off by the intake manifold gasket. But, if a vent was drilled through the manifold to suck gases out of the vent tube, that would explain why it goes up so high.
 
Don't think it's really sealed up there...just low headroom.
Under the manifold is a good way around on an aftermarket manifold, I think. I'd probably run a tube or hose over to the vent stack.
I think the setup I describe was started about 1941 or two, from the manuals I have...Canadian military stuff. I have most of one setup.
 
Yeah, Bruce, I don't think that it was intended as a "sealed system", I think it was just intended to persuade vapors that direction. My original idea was to cap the internal breather to seal it a bit more and then draw off that tube with the PCV under the intake to do some sucking. I get excited just writing on this thread.
 
The only thing that might be a draw back on having the valve under the manifold is if it started to stick or get stuck open like they eventually do and you'd have to remove the manifold to change it. The idle gets real erratic when they start to get gooped into the open position. RPM will go way up then way down over and over a gain. At least you can usually tell what's causing it that way.

Kerby
 
Yeah, it won't be optimum but aesthetics prevail here to hide the thing. Besides, if it sticks, it probably will be time to check that the Johnsons are still set OK.

Kerby, sometime we gotta meet around SAT to discuss flatmotors. Going to Riley's today with the flattie. 67 degrees for a forcast high, great! Lou
 
Several years ago there was an article in the V8 Times about installing a PCV in the lower portion of the intake manifold.. It sounded like a neat idea except the manifold had to be removed to service the PCV. An additional problem could be that the valve would have a tendency to suck oil from the valley area in lieu of just air. No mention was made in the article about putting a baffle over the PCV.
The nice feature was that air would be drawn through the stock breather cap then into the intake with no tubes/hoses, etc.
I have two vehicles, a '57 & 59 which have Ford Y blocks. I used the PCV setup from a '64 Ford 292 Y block truck... Works great and does not look like a modification. I had to block off the draft tube, lower left of the block.. I did this with a flat plate behind the draft tube filter assembly.
 
i had a 64 GMC pickup with a 305 E V6 it had the PCV valves under the valve covers threaded into the heads, so if i blank off the vent in the oil pan and put one of those GMC pcv valves into the intake that would work?
 
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