WB One Tonner master cylinder.

[Oz_ek]

Gents I'm looking for info on an original PBR brake master cylinder as fitted to WB Holden one tonners.
If anyone has a WB Tonner with its original type PBR master cylinder with built in proportion valve I need to know the crack pressure number, this number is stamped on the front of the master cylinder (see pic)....The numbers are usually crudely stamped and hard to read.

Thanks.

[Oz_ek]

Another example from a Sedan of the same era.

P1070245.JPG

[GtoGeoff]

Try contacting PBR.

[Oz_ek]

Try contacting PBR.

Does PBR still exist in Australia?

[HQ 368]

Does PBR still exist in Australia?

I'm not sure if they are still manufacturing, they are/were on East Boundary road in East Bentleigh if that helps

[Oz_ek]

I'm not sure if they are still manufacturing, they are/were on East Boundary road in East Bentleigh if that helps

I remember the factory on the corner of Boundary and North roads, factory is still there although no longer operating as PBR.....Stands to reason with the decline of vehicle manufacturing in Australia.

[swampy]

HI
Bosch purchased PBR. Master cylinders are about the only remaining stock . Other parts are discontinued . Bosch does not give a shit about old Holdens .
The other aftermarket parts are all poorer quality some seals fit some don`t hit and miss .

Just buy a new master for ute /rear drum . Donot buy sedan with rear drum or disc both will be wrong .

[Oz_ek]

Thanks for the reply fellas!... Would still like to hear from anyone with info regarding the proportion valve crack pressure for a WB one tonner.

[swampy]

Hi
Crack pressure be around 225 psi for ute rear drum .
Is there a Load Sensing Valve .??? Usually a big lever arm to a hydraulic valve above the diff . This will regulate the pressure according to load upto max 225psi etc.

[Oz_ek]

Hi
Crack pressure be around 225 psi for ute rear drum .
Is there a Load Sensing Valve .??? Usually a big lever arm to a hydraulic valve above the diff . This will regulate the pressure according to load upto max 225psi etc.

No load sensing valve in use on the this vehicle....Did you find the 225 psi rating on a ute or one tonner?
Cheers.

[swampy]

Hi
Hq HZ proportioning valves were different for ute / wagon and statesman / sedan .
There was also disc rear versions which had higher pressures .

[GtoGeoff]

I have a PBR catalog which has some of this info. Will check tomorrow.

[misterskill]

https://ibb.co/Kz87sR6

20201108-095040-Optimized-Optimized.jpg

WB one tonner, 6cyl.

[Oz_ek]

https://ibb.co/Kz87sR6

20201108-095040-Optimized-Optimized.jpg

WB one tonner, 6cyl.

Thanks for the reply!

[GtoGeoff]

PBR proportioning valves:

P6307 used on HQ with front discs, cracking point is 225 psi. This is a simple barrel shaped valve with just two ports, one in, one out. I used one on my Dodge & it worked very well.

P7256 used on HX [ excl S/man ], HZ K'wood. Cracking point 150 psi. Multiple ports.

P7259 used on HX Statesman, p/van, s/waggon, HZ waggon & utes. Cracking point 225 psi, multiple ports

P7305 used on HZ [ excl S/man & waggons ] with 4 wh discs. Cracking point 350 psi, multiple ports.

P7306 used on HZ S/man, waggons with 4 wheel discs. Cracking point 450 psi, multiple ports.