Coolant System Maintenance - Monaco Cayman 2005 Owner's Manual

When performing maintenance, it is also necessary to inspect other components of the cooling system.
Have an inspection performed of the surge tank cap seal and have the cap pressure tested at each oil
change. The charge air cooler and radiator also requires inspection for cracks, broken welds, secure
mounting, and general cleanliness.
It may be necessary to clean the radiator and external coolers more often under certain conditions.
Leaves, twigs, road debris and other contaminants can block the radiator and cooler fins resulting in
reduced cooling system performance. Blockage can vary depending on road conditions, climate, and
regional conditions. Check the radiator and external coolers weekly for blockage, and clean as required.
To clean the radiator and external coolers, compressed air is recommended. In the event that road
grime, oil, or inadequate cleaning with compressed air is encountered, a high pressure washer and
degreaser may be used with caution to avoid excess pressure that can bend the radiator fins.
Refer to the Cummins OEM manual for detailed maintenance and service procedures. These services
include: draining the engine coolant, flushing/cleaning the cooling system, inspecting the water pump
standpipe, replacing the thermostat, gasket and seal, and replacing the coolant and SCA element.
Coolant Hoses:
Rotten, swollen and worn hoses, as well as loose connections, are frequent causes of coolant system
problems. Overheating can be caused by a collapsed hose or a clog caused by rubber shedding from a
rotten hose. Replace any hose found to be cracked, swollen or damaged. Connections should be
inspected periodically and hose clamps tightened.
Inspect all hoses, clamps, and fittings for leaks due to cracking, softness, and loose clamps/fittings.
Look for signs of fluid leaks, damaged end fittings, ballooning, chafed, kinked, or crushed hoses, and
loose clamps and fittings. Correct any deficiencies found.
Coolant Overheated:
If the engine is overheated, never pour cold coolant into a hot engine. The sudden change in temperature
may crack the cylinder head or block. If the engine is hot, fill slowly to prevent rapid cooling and
distortion of engine castings.
Inspect the radiator core and CAC for dirt and debris build-up. Wash any accumulations using high-
pressure water, being careful not to damage the fins from excessive pressure. Any grease or oil build-up
should first be treated with a non-caustic degreaser to ensure a thorough cleaning.
Coolant System - Thawing:
If the coolant system becomes frozen, the motorhome must be towed. Place the motorhome in a warm
area until completely thawed. If the engine is operated when the cooling system is frozen it will result in
engine overheating due to insufficient coolant circulation. Once thawed, check engine, radiator and related
components for damage caused by expansion of frozen coolant.
Cayman 2005

Coolant System Maintenance

Chassis Information --- Section 10
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