Download Open cap with detent (2) or 2-stage cap (2a) expansion reservoir (1) or radiator. NOTE: – Cap with detent (2): Rotate cap with detent (2) carefully to first predetent, release pressure, then unscrew cap with detent (2). – Model 163: Rotate 2-stage cap (2a) or 1-stage cap half a revolution in anti-clockwise direction, release pressure, then unscrew 2-stage cap (2a) or 1-stage cap. Set heating switches to maximum heating capacity – All except Model 163 NOTE: Model 163 has no pulsed valves. Coolant is permanently flowing through the heating system heat exchanger. Inspect Check coolant level, if required adjust correctly. NOTE: In case of inadequate antifreeze content, Replace coolant against a separate job order. Fit the test cap (3) on the expansion reservoir or radiator Connect tester Apply pressure to cooling system and check leaktightness of cooling system Inspect cooling and heating hoses as well as their connection points for proper condition and loss of coolant, replace coolant hoses, if necessary. Check condition and seating of hose clamps and retighten or replace if necessary. Install in the reverse order.