1972 Bedford Bus

I'm helping a friend with a 1972 Bedford Bus with a 300 petrol & a Comair body.
It has a Clayton Dewandre brake system but I'm not sure if it's air/hydraulic or vacuum/hydraulic.
The compressor/exhauster needs attention as it sucks from the front side but has nothing from the discharge side, & can't get the head off it without removing the manifold. It has some bodgie hoses swinging in the breeze behind the gearbox, so I'm not sure which way it's supposed to be connected. Hope someone can help me out.

The TS 1087 manual says;

For Vacuum assisted hydraulic systems:

On petrol engines, the servo uses the manifold vacuum.
On diesel engines, the servo uses a vacuum from an exhauster which is connected to a vacuum reservoir and then to the servo.

The exhauster is mounted on the timing case cover and driven from the timing gears.

Your post doesn't make logical sense; the petrol engine doesn't have an exhuaster.

hope this helps

This is how the Clayton Air/Hydraulic system works.


Standby working on the picture. I have the vacuum diagram as well just hunting.

I tried to put these up yesterday, but for some reason they didn't show.

The first photo show the master cylinder, the servo and the air pressure vessel on the end. (It's the bottom side showing.)

The second photo is the air compressor.

Are you sure you have a petrol engine and not a diesel engine?

Don't damage the master cylinder; they are become rare and hard to find parts....

It's definitely petrol, it's got spark plugs, a dizzy & a carby.

Ok,

if there is not output, you can approach it 2 ways.

remover the compressor and strip it down. rings, unloader valve, intake valve and seat.

or remover the compressor head and do the top end first. seals, valve and unloader.

The unloader pipe seems to be broken off...........so its likely the compressor has been pumping continuous at relief pressure = lots of heat in the valves.......simplest thing to do is to remove the hex nuts on the head ,and see what the valves and springs look like....be aware ,if you remove the head ,the barrel will likely come off too,and you will have to refit the piston and rings.............you can buy these little Claytons new for a few bucks from surplus,but parts from a brake place will be very costly........everything from a brake place will be costly.

Where is the "Unloader" pipe that you say is broken off? JOHN.K.

this might help.

The hose is from the governor to the compressor and "tells" when the compressor is to stop compressing.