hydraulic clutch residual pressure valve

[bostru]

Where can I buy a residual pressure valve for 1960 GMC Pickup with hydraulic clutch. And does anyone know what the pressure value is in P.S.I

[Funky61]

Welcome Bostru!

Is this valve on the hydraulic slave cylinder and would you mind posting a picture?
If it is, I know that some did not have that valve on there.
My 61 does not have one; it just has a bleeder screw.

[bostru]

Truck is in storage so I can't get pics but the valve is at the slave cylinder right where the line goes into the cylinder . It is about 3/4"long looks like a brass adapter. Not all trucks used these apparently but were used in brake systems on early cars and trucks where the master cylinder was located on the frame . idea was to hold slight residual pressure (approx. 10 PSI)
on the brakes . I assume this valve does the same with clutch

[James]

Originally Posted by bostru

Truck is in storage so I can't get pics but the valve is at the slave cylinder right where the line goes into the cylinder . It is about 3/4"long looks like a brass adapter. Not all trucks used these apparently but were used in brake systems on early cars and trucks where the master cylinder was located on the frame . idea was to hold slight residual pressure (approx. 10 PSI)
on the brakes . I assume this valve does the same with clutch

The purpose of the pressure is to make sure the wheel cylinders/slave cylinder seals from collapsing and allowing fluid to leak out. This is used on all vehicles with drum brakes/hydraulic clutch. With drum brakes it is located in the master cylinder. On the clutch I am not sure if it in the clutch master cylinder (I would think it would be here) or the slave cylinder.

[bostru]

The residual pressure check valve in a brake system is to keep slight pressure applied to the brakes at all times which will reduce pedal travel and make the brakes apply quicker . (probably splitting hairs as to how much quicker) .The valve in the hydraulic clutch system works in the same way . Do you know where I can get an OE valve for the clutch on a 60 GMC with a 305 ?

Thanks for your reply

[James]

Originally Posted by bostru

The residual pressure check valve in a brake system is to keep slight pressure applied to the brakes at all times which will reduce pedal travel and make the brakes apply quicker . (probably splitting hairs as to how much quicker) .The valve in the hydraulic clutch system works in the same way . Do you know where I can get an OE valve for the clutch on a 60 GMC with a 305 ?

Thanks for your reply

I know a lot of website is saying the same thing. However applying brake quicker was not the original issue, it is leaking wheel cylinders. Please refer to the expert at: https://www.freeasestudyguides.com/r...eck-valve.html
This is in a practice ASE test.

[bostru]

Thanks ,do you know where I can get one for my clutch and do you happen to know the value in PSI for the clutch valve

[Funky61]

I would check with this company

https://www.wilwood.com/Search/PartN...ual%20pressure

I’m certain they could provide more specifics as well as the valve.

[jagarra]

These are available. https://www.speedwaymotors.com/Wilwo...gs,233816.html

[bostru]

Thanks, Funky61 and Jagarra I am aware of the aftermarket valves but am looking for an Original Equipment piece for another project N.O.S. or nice used .
Thanks again