Document Ref 903647-001 Rev 3
Page 4-5
Component Technical Manual
PAS V3 Pump for Fuel Dispensers
Issue B
4.7
Air Entry on the Pipework to the Storage Tank
Check if there is a leak in the fuel piping from the storage tank to the dispenser.
In the piping systems with more than one pump per suction line, check the non-return
valves on each derivation when present.
If there are no special valves for this purpose, the valves of the filter box take over this
function (they must exist on all dispensers). It is possible that one of these valves is not
closing properly and is allowing air into the pipeline. When the problem can not be found,
it is possible to mount a sight glass underneath the pump filter box to check for leakages
and to define the leakage (contact Tokheim Hydraulic Department).
The wrong foot valve can be detected by delivering about 20 litres with each pump and
check if the delivery is immediately starting when the motor starts and stays constant.
After visual checking the parts of the pipeline (valves, hinges, bent pipes, and so on) get
in touch with specialised departments to make a hydraulic improvement on the fuel piping.
