Volvo Symptom D12D US02 Service Manual page 46

Group 20
and sequence of checks depend on results from Basic
Checks (including active or inactive fault codes noted),
vehicle conditions, vehicle service and repair history,
other symptoms, and information from the driver.
•
"Step 1: Fault Code Readings" page 43
•
"Step 2: Visual Inspection (System Checks)" page 43
Engine Oil/Coolant Contamination
Engine oil and coolant contamination normally occurs
because of faults, leakage or break down in the engine oil
cooler, water pump (D12D), or cylinder liners. Because
oil pressure is higher than the pressure in the coolant
system, coolant is usually contaminated with oil.
However, in certain conditions, engine oil also can be
contaminated with coolant. For example, this can occur
when the seals at the coolant pump (D12D) and cylinder
liners are damaged.
The following checks should be performed in order until
the fault is found. These checks also can help exclude
components with no faults or malfunctions. The amount
42
•
D
"Step 4: Component and Function Checks" page 44
"Contaminated Fluid" page 41
and sequence of checks depend on results from Basic
Checks (including active or inactive fault codes noted),
vehicle conditions, vehicle service and repair history,
other symptoms, and information from the driver.
•
"Step 1: Fault Code Readings" page 45
•
"Step 2: Visual Inspection (System Checks)" page 45
•
"Step 4: Component and Function Checks" page 46
"Contaminated Fluid" page 41