Ted, I will take your advise and use a carb plate, as I have the luxury of extra room. Thanks for the help.

1959 and 1960 f-100sAkron OH

The back edge of the manifold comes over the hole in the valley pan just enough to prevent the tube from being installed or the intake from being installed.    This is  intake ___________     o= hole

                                    oooo   just wont fit

there is about an 1" clearance between intake and pan. intake comes over the hole about 1/2 inch or so. If anything will fit in the hole it will have to be at an angle. Which may be homemade as the best bet for now. I have breathers for the valve covers which I intend to install later but I may have to do that now. 

55Birdman  Hickory NC

OK - back to basics - what clearance exists between the old draft tube port and the bottom of the tri-carb manifold? Is it an inch? What do you have to work with? I don't have access to one of the manifolds to look at it. PCV valves provide several practical functions - (1) they provide a high vacuum source to ventilate the engine interior with a checkvalve to prevent backfires from pressurizing the engine case and (2) they also restrict the volume of air ingested into the intake so as not to complicate idle control at the carb. 

Is there room for a "cookie" (of whatever suitable material), an O-ring and a capscrew to hold it down? That would eliminate the draft tube exit on the valley (for good or for evil). It won't be the puke point anyway.

The engine still has to vent. Over the years (many) - not necessarily the Y's - have vented via atmospheric breathers on the two valve covers. This may not be the way you prefer to do it - but two breathers on a couple of tin covers would let you run the motor while you work this out.

There are caps for the top of the forward valley cover tube that are closed - have only a shiny top and a hose fitting out the side. Attaching this port to an elbow in the underside of the center carb air cleaner will put (some) vacuum on the vent. This system won't necessarily require a PCV valve - but (depending on engine condition) it may require a restriction to keep from heavily oiling the carb.

Another idea - at lower left front on the side of the block is the old style draft beather port. Many are now capped. Intall a PCV valve at this point and run a vent hose up to an elbow on the bottom of the center air cleaner. Use a free flow pleated element cap for the forward valley tube. 

You want the engine to have ventilation sufficient to avoid pressurization - and oil loss control. Try a few things and see what you (and the engine) can live with.

 
 Steve Metzger       Tucson, Arizona

Hello Earl,Kinda got of topic there.Can you not drill and tap into manifold near  centre carb same as was suggested to the other fellow?Put in a screw-in PCV valve and run a hose from an elbow and grommet where you have a hole now?Doesn't require a spacer at all.

  

Birdman:

If Charlie's plan doesn't work, some kind of 90 degree fitting might work, but you don't want it to be a pcv valve.  A pcv needs a vacuum connection.  Just a thought, but might a  copper pipe or pcv plastic 90 degree elbow work somehow?  You could even use a rubber/vinyl hose for the downdraft, just keep it off the exhaust pipe.  Maybe a visit to a home improvement store is in order.

There were two types of draft tubes.  One has a round cannister-looking part that bolts to the valley pan and the draft tube is weldede into the side of that cannister.  The other type looks like someone cut a straight tube off at 45 degrees, rotated the parts 180 degrees and welded them back together to form a sharp 90 degree bend.  The first type needs more room than the later one.  Which do you have?

John in Selma, IN

John - "The Hoosier Hurricane"

Surely someone must have the 573 with road draft. My solution would be to find a spare road draft tube, a bfh, and make it fit.


Lawrenceville, GA

My valley pan has a baffle on it.I think you guys have dropped MY question and started answering the OTHER question. My downdraft wont fit anymore due to the intake  When I drive the car it blows out the hole like  whale. I need to stop that. I am thinking PVC valve. But I cant install spacers because my hood wont close. I need a temp fix for a few months till I can begin rebuilding the engine. The downdraft tube simply vents the exhaust gases down and out of the engine near the starter. Can I install a 90 degree PVC and a tube send the exhaust gases down by the starter as it is now?   MY QUESTION ONLY PLEASE

55Birdman  Hickory NC

Where one side of the PCV valve goes into the crankcase (valley pan in your case), the other end goes to a direct vacuum port either at the bottom of the carburetor under the throttle blades or a carb spacer or by using the direct vacuum port in the intake manifold.  Mark is absolutely right in that the closer that the direct vacuum port in the intake manifold is to the carburetor(s), then the better.

Lorena, Texas (South of Waco)

Do what Charlie said, Screw or glue a baffle that seperates oil from air on the bottom of the valley. I made one from sheet metal for mine. Just make the air reverse direction and give the oil a way to drain out.

Frank/Rebop

Bristol, In ( by Elkhart) 

I would not use the baffled grommets.  I used some and they significantly reduced the ability of the breathers to breathe.  You will be better off welding, perhaps even JB welding, a real baffle in place.


Lawrenceville, GA