300SD (140.134) L6-3.5L DSL Turbo (603.971) (1993)
Remove. See: Blower Motor/Service and Repair
Pipes on heat exchanger
Close, screws (23) and assemble with new O-rings.
Heat exchanger (22)
Release (screws 21).
Heat exchanger (22)
Remove.
Heater housing
Clean from inside, remove any coolant which may have escaped.
Install
In reverse sequence.
Coolant level
Correct.