I have another question, if you removed the RD tube and built the plate with a threaded boss and ran a tube with a PCV on it to the intake would that work, reason I ask is I'm also swapping a 261 in place of a 235, both scrub, and the 261 has a canister similar to the 235 but it is set up for a PCV.

The mesh "filter" inside the canister is there by design catch oily vapors and  ultimately it will run down into the drain hole. Problem was it often was plugged by sludge, and moisture; many a can I removed back in the day was just a mass of goo and rust. PVC valves are a lot kinder to engines as ventilation always occurs. Road draft tubes worked OK in the country; not so in the city for reasons already discussed.WLJ

The valley cover with no road draft tube or PCV was pretty much standard until 1961 ( not sure about Birds ). In 1961 they came out with a new block casting that didn't have a hole for the road draft tube. So 61-64 valley covers have that provision. I'm using one from a 62 truck on my 57 292 that has the PCV valve in the valley cover and a block off plate were the road draft tube was.

           In place of the road draft tube What we did  in  the 64 half ton was to  install  rubber grommets into the Valve cover and a  pipe  into the exhaust header!   I went to the Auto wreckers and picked up two anti reversion valves to install into a rubber hose that  I run from the valve cover  to the  header
I have been using this method on my drag Cars for years and  have had good results!   I know this is not an option for the guys that are trying to keep the car pure stock but it does  keep the  pressure out of the engine1

OK, this brings to mind another question, the previous owner put this 312 in a 2 ton truck, from what I could tell they used  a bunch of truck parts to make fit, I found a reciept for what I think is a long block, the numbers don't seem to come up at the dealer where it came from, so most of the 272 parts were used to hack this together, I've got most all of that straightned out,but is the valley cover different from the one on here, this one just has the tube to put oil in and nothing else, I cleaned the filter and the road tube but noticed that it is strangely built,the drain back tube leaves oil in the housing as it is higher than the bottom of the bowl.

The reasons they may leak has already been covered.. However, some very late Y engines had a PCV setup, but some engines such as in T.Birds had the rear valley downdraft tube earlier. That valley cover can be modified by removing the tube & installing a PCV valve setup. Minor modifications to the valley cover are needed to install the grommet & valve..  However, the baffle underneath should be retained, to avoid drawing oil into the PC valve  


Paul

I just rebuilt A 312 because of oil running out of the rd tube, it did need an over haul, but is this common of them to drip out of the rd tube and if so what is the later valley cover off of with the pcv valve.

Check out all of the above mentioned possible causes.  Also remove the oil filler cap & check the filter screen. It's the only air input for the crankcase venting on stock engines. If it's plugged up with dirt & oil residure, it will contribute to pressure buildup in the crankcase..
 


Paul

the nut on the breather is on a thin piece of tin,if it has bin over tightend it will bend then not enough presure to seal the gasket. take it of and with no gasget make sure the cover is seated  if it does not fit the can you need to bend the nut so ther is good tention when asembled with a gasget,these breathers ar not the highlight of ford engineering. good luck

It's probably best to remove it and thoroughly clean it.  There is a sort of filter inside that can get clogged up and should be replaced if so.


54 Victoria 312;  48 Ford Conv 302, 56 Bird 312
Forever Ford
Midland Park, NJ