PCV Vacuum Source

[Stumper]

Does anyone have a diagram or know where the PCV valve got its vacuum from on a 62’ 361/4bbl. The carb for these was 3253s AFB but the only vacuum port on these was a small one for the distributor. Im thinking of putting a PCV setup on my car but can’t figure out what the OEM correct source was for vacuum. My TM doesn’t show anything..

 

[khryslerkid]

3257s

 

[Beekeeper]

silly me

 

[Beekeeper]

Here’s a pic of a PCV valve

 

[R/T Boy 67]

Not all 62 mopars had pcv valves, which is why your carb doesn't have a fitting for it.

 

[khryslerkid]

If it came from California it had pcv. Otherwise it had the breather tube on the right side.

 

[pedal2themetal]

HI A picture is worth a bazillion words... can you shoot a picture of the top of your motor. then we can see whats up... but Wow the one that is pictured sure doesn't have any provisions in the intake for a port..

good luck take care be safe
tim

 

[Stumper]

Thanks for the pictures. I see the correct valves are available at Mopar vendors but couldn't figure out where to get vacuum. That port in my current carb is closed off. I have another 3253s and it too has the port closed. I guess if I were to go ahead with changing over I’d have to drill out the port and solder in a nipple?

 

[Stumper]

Thanks for the pictures. I see the correct valves are available at Mopar vendors but couldn't figure out where to get vacuum. That port in my current carb is closed off. I have another 3253s and it too has the port closed. I guess if I were to go ahead with changing over I’d have to drill out the port and solder in a nipple?

 

[Moparnocar]

3257s

View attachment 1302522

View attachment 1302524

Not to get " off topic" but plastic fuel filters are the #1 cause of engine fires, especially when banging around.. . But of course, it's up to you to change or not

 

[khryslerkid]

Not to get " off topic" but plastic fuel filters are the #1 cause of engine fires, especially when banging around.. . But of course, it's up to you to change or not

That was a picture of the engine when I first bought the car.

Now...

 

[Stumper]

Couple more questions. In this picture of a 3253s where the bunghole for the vacuum connection would be. The hole itself is around 1/2”. At the bottom of the hole is a divot that’s maybe 1/4”. If you were to drill the hole out to install a nipple would you drill it out to full size - or just the 1/4” size? How did Carter do them?

 

[khryslerkid]

Is there a void under the carb where the port would enter if drilled out?

 

[Stumper]

Is there a void under the carb where the port would enter if drilled out?

I “assume” there is ….. I haven’t taken either carb apart to confirm.

 

[Beekeeper]

I “assume” there is ….. I haven’t taken either carb apart to confirm.

The port would come out on the bottom side of the carb and has a notch of sorts around the Venturi that would allow the nipple to see engine vacuum.

 

[khryslerkid]

Should look similar to this underneath.

 

[Stumper]

Mine is the same as that 49226. I guess since the hole on the underside is 1/4” it wouldn’t accomplish anything go larger at the opening. I think after I rebuild this spare carb I’ll go ahead and punch it out and install a vacuum nipple. Thanks everybody!

 

[Dan64]

Mine is the same as that 49226. I guess since the hole on the underside is 1/4” it wouldn’t accomplish anything go larger at the opening. I think after I rebuild this spare carb I’ll go ahead and punch it out and install a vacuum nipple. Thanks everybody!

How about a carb spacer with a vacuum port in it?

 

[Stumper]

How about a carb spacer with a vacuum port in it?

That would work but I’m trying to stay as original as possible.

 

[RJRENTON]

How about a carb spacer with a vacuum port in it?

Mine is the same as that 49226. I guess since the hole on the underside is 1/4” it wouldn’t accomplish anything go larger at the opening. I think after I rebuild this spare carb I’ll go ahead and punch it out and install a vacuum nipple. Thanks everybody!

Bear in mind that the idle fuel feed circuits MUST BE CALIBRATED to accomodate the additional air entering the engine. There are hydrocarbon energy (as oil and fuel vapors) in the PCV system that will also effect the idle and off idle fuel transition circuits that will need to be determined. If, the additional air is not accommodated, a large flat spot, almost to the point of a lean stall may develop. Likely, the static and dynamic ignition curve will need to be developed. Just be aware that it is not as simple as drilling the carb to accomodate a hose connection. Just my opinion of course....
BOB RENTON