From Bill Coburn
Here is an exact cut and paste from Tee One Topics :
" Everyone seems to know how to do this but perhaps a description might be a worth while reference.
The hydraulic system recirculates and to some extent bleeds itself. The pumps are fed by gravity from the reservoirs.
They then pump to the accumulators through the control valves. When the accumulators are fully charged the output from the pump is redirected back to the reservoir.
Brake fluid from the accumulators remains under full pressure from the accumulators to the brake actuation valves in the ‘rat trap’ and to the height control valves on the sub frame.
Both of these assemblies have provision for the fluid to return to the reservoir after it has done its job in the brake callipers and/or the rear rams.
As this return is not continuous and as there are lots of places on the way for air to get trapped, these circuits need to be bled."
Source: Tee One Topics issue # 37