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New owner struggling with brakes

Hi all, recently bought a 1933 PD. I'm slowly working my way through the brakes but am a bit puzzled by the cross shaft. The inner & outer shafts seem locked together & I'm not sure if they are seized or locked on purpose. What would the detriment be if they are seized? All four brakes operate. Any advice would be much appreciated .
Kevin.

Location: Yorkshire

Re: New owner struggling with brakes

They are pinned together near the middle. The theory is the outer takes the torque from the pedal to the middle of the inner shaft. The togque is then split evenly back outwards to the levers for the back brakes.

Re: New owner struggling with brakes

Hi Kevin, the inner and outer cross shaft on your car is pined and plug welded in the centre, this compensates for any twist in the shaft under braking load, I posted pictures on a thread a while back. Have you tried the search facility, there is a lot of good stuff on brakes here, if that fails to clarify for you we can probably help with specifics.

Edit; Snap lol!

Location: NZ

Re: New owner struggling with brakes

Hi Kevin

The idea of the concentric cross-shaft tubes is that braking effort is transferred from the offside pedal down the inner tube to the mid-point of the car (where it is pinned/welded), and thence back out to each side to the rear brakes. The inner and outer tubes may indeed have become rusted together. But even if they are free, they are both very stiff and the amount of differential twist between one and the other is tiny. This makes it quite hard to see even when an assistant is "standing" on the brakes and applying a lot of torque to the tube, let alone just levering it with hand tools when testing it off the car. Nevertheless, with mechanical brakes it is force which matters, not movement.

The main effect of seized tubes is that the now "solidly" connected rear offside brake tends to work harder than the "springily" connected rear nearside one when you are braking hard, and may even lock up in an emergency stop. To some extent you can allow for this by slackening its cable a tiny bit, but the rear brakes will never be balanced at all degrees of braking. What tends to happen is that as you increase pedal pressure, the nearside rear brake begins to work first, then the offside brake "catches up" and eventually exceeds it in effort. I have seen this during the MOT roller test.

The front brakes are reasonably balanced side-to-side by the half-moon compensator, and since they contribute more than 50% of the total braking effort a bit of imbalance at the rear doesn't seem to be a serious problem in practice.

Location: New Forest