The SUNTEC AE oil pump is the basic model incorporating a pressure regulating valve. It does not have a cut-off feature, this allows purging of air through the nozzle line.
The gear set draws oil from the tank through the built-in filter and transfers it to the valve that regulates the oil pressure to the nozzle line.
All oil which does not go through the nozzle line will be by-passed through the valve back to the return line, in a two pipe installation or, if it is a one-pipe installation, back to the suction port in the gear-set. In that case the by-pass plug must be removed from the return port and the return port sealed by steel plug and washer.
Bleeding in two pipe operation is automatic.
In one pipe operation, during the starting period, air is purged through the nozzle line : the by-pass hole of the nozzle plug allows air to pass to the nozzle line without opening of the regulator valve.
For the first start up, bleeding can be accelerated by loosening the plug in a pressure gauge port.
Owing to the presence of the nozzle by-pass hole, the pump has no cut-off function. Cut-off must be provided by an external solenoid valve (as mentioned in the paragraph APPLICATIONS).