PVC Valve on an Ohhy 4 bl intale
 

I'm installing an Edelbrock carb on a 294 flathead. The intake is an Offy 4 bl with carb adapter. But the holes for the road draft and oil fill are not bored. I don't want to bor them. Oil fill is the poriginal fuel pump but need a PVC system. Thanls.
Gramps

Re: PVC Valve on an Ohhy 4 bl intale
 

Wonder why this is poated twice??
G

Re: PVC Valve on an Ohhy 4 bl intale
 

I see three posts now. 8^)

Re: PVC Valve on an Ohhy 4 bl intale
 

Be nice if I could get some help here? Don't need a breather on the fuel pump, makes a real mess??
G

Re: PVC Valve on an Ohhy 4 bl intale
 

I don't have a problem with the breather on the oil fill making a mess on my engine. Been running it for 25 years. No PCV.

Re: PVC Valve on an Ohhy 4 bl intale
 

I run tubing from a xler style breather to the air cleaner. It has a built-in flame arrestor mesh No PCV.




https://www.fordbarn.com/forum/attac...1&d=1681408953

Re: PVC Valve on an Ohhy 4 bl intale
 

Ron, what type of oil pan are you running?
The 1935 through 1948 pans use an opening at the bottom front as the breather. I doubt you want to pull road dust into the engine by using a vacuum at the top.
If 49-53 type the you may not have any filtered air inlet for the system.

Re: PVC Valve on an Ohhy 4 bl intale
 

No vacuum. Entrains crankcase vapors when not moving. When moving the draft tube will overwhelm entrainment. If you worry about dust while not moving, just stuff stainless steel scouring mesh in the draft tube.

Re: PVC Valve on an Ohhy 4 bl intale
 

My understanding from the first post is there is no draft tube on the engine in question.

Re: PVC Valve on an Ohhy 4 bl intale
 

Yeah, maybe? But I'm not quite sure what was meant by "the holes for the road draft and oil fill are not bored" ? Are the holes blocked off? How do you add oil if the oil fill hole is blocked off? Through the dipstick?

Re: PVC Valve on an Ohhy 4 bl intale
 

Thank you, thank you Guys, thought I was lst here. The Offy 4bl intake is a casting that is used for ALL models of flatheads. But the macine work is different between te pre 49 and the early models. the oil fill and the road draft are not machined so you have to use the oil fill fuel pump stand. I was considering using a PVC system, but didn't know what valve to use. Now I can just plum it into the air cleaner. Simpe solution. Plus a few other options.
Gramps
PS the engine has 3 97's on it now. rns rich in cruise and no matter how I jet it can't get it right. This much gas running thrugh the engine is bad for the rings and pocket book. The Edelbrock 4bl is easy to tune gives good mileage. Anybody need a stromburd tri carb system??

G

Re: PVC Valve on an Ohhy 4 bl intale
 

Offy used their 49-53 adapter castings for use on the early 32-48 application.
The oil fill and road draft holes were just not installed in the early intakes.
https://www.fordbarn.com/forum/attac...4&d=1681475533

Re: PVC Valve on an Ohhy 4 bl intale
 

Yeah. All good now. It's essentially the same intake design as on my original early 38 21-studder. My Xler breather sits atop the pump stand. It's hose plumbed into the air cleaner. Takes care of any crankcase stink & messy mist when the car's not moving or no breezes blowing past the pan draft.. 8^)