4-19. WINTERIZATION SYSTEM - Continued
While supporting the pump body heater, remove capscrews (8) attaching heater to hose body.
Remove heater from pump body via the pump body door.
Remove fan and fan mounting plate from the heater housing by removing the four screws.
Pressure test heater core with compressed air. Blank outlet connection. Connect air pressure hose to
Place assembly in water bath and ensure it remains under water.
Slowly pressurize the core up to a maximum pressure of 20 psi (140 kPa). Check for air bubbles (5).
Repair or replace heater core as required.
Replace fan and fan mounting plate on heater housing and replace four retaining screws.
Spin fan wheel with finger and check the fan and housing do not rub together.
Insert pump body heater through pump body door and align with holes on hose body front panel.
Tighten capscrews (8) attaching heater to hose body.
Reconnect electrical connections to motor.
(4) Slip air intake hose (3) over air intake nipple (2) and heater (4), tighten hose clamps (1). If hose crimp
retaining pliers were used to isolate the heater, remove the pliers.
Close radiator drain valve. Top up radiator.
Ensure winterization circulation valves on engine are open.
Start APU and allow water to circulate. Check all connections for leaks. Tighten/remake as required.
While APU is running, loosen connection on pump body heater outlet and bleed air from top of heater.
Retighten hose clamp.
Top up radiator as required and replace radiator cap.
Stop APU and start main engine. Allow engine to reach normal operating temperature and shutdown.
When engine is cool remove radiator cap and top up radiator as required.