Charge Air Cooler - Monaco Cayman 2005 Owner's Manual

CHARGE AIR COOLER

Operation:
The diesel engine uses compression to ignite the fuel/air charge. To increase compression inside the
combustion chamber (resulting in increased power output) a turbocharger is added to the engine. The
turbocharger is a paired housing assembly with impellers inside each housing connected by a common
shaft. One impeller is propelled by the engine exhaust, which drives the other impeller. The function of
the other impeller is to increase compression inside the combustion chamber by forcing air into the
intake manifold. This process works well, however, the intake air charge is heated two different ways.
Through convection by the exhaust gases driving the turbocharger and any time air is compressed heat is
produced. This has a negative effect inside the combustion chamber resulting in lost power potential.
Therefore, a Charge Air Cooler (CAC) is installed to cool the intake air before it enters the engine. The
CAC performs the same function as a radiator, cooling air instead of liquid. Ambient air passing
through the CAC will cool the engine intake air charge.
After leaving the turbocharger, intake air is compressed and heated to approximately 300º to 375º F.,
depending on the engine load and throttle position. Before air enters the intake manifold, the CAC cools
the intake air temperature to the engine manufacturer specifications. Lowered intake air temperatures
reduce exhaust emissions, improve fuel economy and increase horsepower. The CAC will continually
expand and contract up to ¼" as throttle increases and decreases.
Cleaning & Maintenance:
Visually inspect the charge air cooler, every six months, for dirt and debris that may be blocking the
fins. If the motorhome develops an oil leak, there is a possibility that the oil will coat the fins of the
CAC. Dust will adhere to the oil film and eventually clog the fins, greatly reducing cooling efficiency.
When the oil leak is repaired, the CAC must be thoroughly cleaned.
During each oil change inspect the engine side of
the radiator/CAC assembly for foreign objects that
may cause restriction.
Spraying degreaser on the charge air cooler, as
well as using a steam cleaner, will not damage the
CAC. However, pressure washer and steam clean-
er nozzles placed too close to the CAC can bend
the fins. The recommended cleaning procedure for
the CAC and the radiator, is to use a bucket of mild
soap and water. Carefully wash with a bristle brush
then rinse using a garden hose, with minimum water
pressure, standing back a distance to avoid bending
the fins.
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Section 10 --- Chassis Information
090388d
Cayman 2005