INTRODUCTION
The Fuel System Inhibiting Rig is used to inhibit the fuel systems of aircraft engines.

GENERAL
The rig consists of an inhibiting fluid tank with a capacity of 18 litres (3.97 gallon) mounted on a welded, tubular steel frame. The rig runs on two 9” diameter wheels with rubber tyres. A stand at the front of the rig steadies it when in use. The inhibiting fluid tank is equipped with a filler cap with gauze strainer, a pressure relief valve, air inlet and fluid outlet and an inhibiting fluid delivery hose, is stowed on one side of the rig.

A hand pump is located at the front of the rig and a control panel, containing a pressure regulator and auxiliary air inlet adaptor, is located at the rear of the rig. The fluid in the tank is pressurised by air supplied from workshop air via the auxiliary air inlet adaptor located on the control panel, alternatively, the supplied hand pump can be used to pressurise the tank. The pressure in the tank is regulated by a pressure regulator installed on the control panel. The maximum pressure in the tank is 4 bar (60 psi). A pressure gauge mounted on a manifold block at the rear of the control panel, indicates the pressure in the tank. A pressure relief valve located at the top of the tank is set to relieve the pressure in the tank if goes above 4.5 bar (65 psi).

When the inhibiting fluid tank is pressurised, and the 1⁄2” BSP fluid outlet ball valve is opened, inhibiting oil is forced out of the tank through a nominal 2 micron filter and a 4m (159”) long, 13mm (1⁄2”) nominal bore delivery hose; the hose terminates in a 3⁄8” BSP Hansen socket suitable for connection to the aircraft engine for internal inhibiting. A corresponding plug, with wire lanyard, connects to the socket to prevent ingress of dirt when the hose is not in use. The hose is stowed on brackets on the side of the rig.