39 Intake manifold wiper vacuum connector

[Joe KCMO]

What is the size of the compression fitting which holds the windshield wiper vacuum tube in the intake manifold on the driver's side rear of the intake manifold. The head of mine is broken off and I need to remove the old one (I do not know how) and then replace with a new one. Any and all help appreciated.

 

[Kube]

What is the size of the compression fitting which holds the windshield wiper vacuum tube in the intake manifold on the driver's side rear of the intake manifold. The head of mine is broken off and I need to remove the old one (I do not know how) and then replace with a new one. Any and all help appreciated.

Hi Joe,
Early '39s had a 3/16" diameter tube while later '39s used a 1/4" diameter tube.
Regardless of the line diameter, the fitting always utilized a tapped hole of 3/8-24 in the valve chamber cover.
The process of removing the broken pieces depends on a number of variables. Is the cover (manifold) on the bench? Is it aluminum or cast?
Once removed you may want to chase the threads with a tap. You must use a 'bottoming tap' and use it carefully so as not to damage the seat. A regular tap will NOT work in this instance.

 

[Gary in Mozarks]

Hi Joe,
Early '39s had a 3/16" diameter tube while later '39s used a 1/4" diameter tube.
Regardless of the line diameter, the fitting always utilized a tapped hole of 3/8-24 in the valve chamber cover.
The process of removing the broken pieces depends on a number of variables. Is the cover (manifold) on the bench? Is it aluminum or cast?
Once removed you may want to chase the threads with a tap. You must use a 'bottoming tap' and use it carefully so as not to damage the seat. A regular tap will NOT work in this instance.

If you don;t have a bottoming tap you can make a standard tap into a botoming tap by griniding off the firt 3 or 4 threads.
Gary

 

[ken ct]

I have the fittings for 3/16 line and think i have one for 1/4" also. ken ct.