2004/06/01 Caterpillar


Troubleshooting a Complaint of Overcooling {1350, 7569}

Usage:

C15 BXS
Engine:
C15 (S/N: BXS1-UP)

A customer may assume that the C15 On-highway Engine may not be at minimum operating temperature in cold weather, or the engine may be operating below the minimum operating temperature. The minimum operating temperature is 71 °C (160 °F) when the engine is at idle. The minimum operating temperature is 80 °C (175 °F) while the engine is running down the road.

Overcooling is defined as excessive heat loss from the engine system. The excessive heat loss does not allow the engine to reach normal operating temperatures. The engine will input heat into the system from the cylinder liners and from the cylinder head assembly. The amount of heat in is a variable that will be constant for a given engine. Locate the excessive heat out. Once the excessive heat out is located you will be able to identify a potential solution.

The dash gauge may not be accurate. Further troubleshooting is required. Complete the following checklist when you are diagnosing a complaint of overcooling .

  1. Describe the complaint:

    Vehicle make and model

    Engine Serial number

    Mileage on the engine and vehicle

    Dealer Code

    Summarize the complaint for overcooling:

    Does the engine run cold at idle?____(Y/N)

    Does the engine run warm at idle but the coolant temperature drops below 80 °C (175 °F) when driving the truck unloaded?____(Y/N)

    Does the truck run cold when the truck is loaded?____(Y/N)

    Is the cap getting heat?____(Y/N)

    Cab Temperature____°C

    Other?

    List all of the heaters or coolers. (Example: internal tank fuel heaters, bulk heaters, transmissions coolers, extra bunk heaters)

    Is the cooling fan on or is the cooling fan cycling when the engine is getting over cooled?________(Y/N on/cycling)

    Does the fan operate correctly in the trucks with the complaint? (The fan turns on when the ECM tells the fan to turn on.)____(Y/N)

    The version of software on the engine________

  1. Verify overcooling with the ECM data. The dash gauge may not be accurate. List your results in the following table.

    Table 1
        Temperature    
    ECM OEM Gauge
    Ambient air Temperature     °C    
    Jacket water coolant temperature at idling (1100 RPM)     °C     °C    
    Jacket water coolant temperature with light load     °C     °C    
    Jacket water coolant temperature with heavy load     °C     °C    

    • If the dash gauge reads significantly different than the ECM, the dash gauge may need to be repaired.

    • If the engine is warm but the cab is not getting heat there might be a problem with the heating in the ducting for the cab.

  1. Leakage from the thermostat

    The leakage of the thermostat is measured at the top radiator hose. The thermostats are rated at a maximum of 10 cc a minute per thermostat.

  1. Check valve for the Vent line

    A check valve for the vent line in overcooling issues has been used in the past. The publication on the check valve for vent line is Truck Engine News, "New Cooling System Vent Line Check Valve Helps Prevent Over Cooling". If this check valve is used on the C15 On-highway engine the check valve must be installed above the tee. The tee connects the vent line for the precooler and the standard vent line together.

  1. Other heater circuits

    Check the routing of all hoses.

    Isolate one circuit at a time. If one of the repairs fixes the issue, a closer look will be required. The possible heater circuits may include the following: fuel coolers, lower radiator hoses and heater for fuel tank .

Caterpillar Information System:

3406E, C-10 and C-12 On-highway Engines Torque Limit Switch Circuit - Test
2004/05/17 Nexus Retrofit Air Conditioning and Heating Parts for Other Than Caterpillar Construction Equipment and On-Highway Trucks {7320}
C11 and C13 Petroleum Engines Fuel Priming Pump
C15 and C18 Industrial Engines Exhaust Manifold
C-10, C-12, C-15 and C-16 Industrial Engines CID 1836 FMI 08 Auxiliary Temperature Sensor signal abnormal
2004/05/01 Special Publication, SEBU6251, "Caterpillar Commercial Diesel Engine Fluids Recommendations" has been Revised {0645, 1000, 1250, 1280, 1300, 1348, 1350, 1395}
C13, C15, and C18 Tier 4 Final Engines Flywheel Housing Cover
C-10, C-12, C-15 and C-16 Industrial Engines E058 Low Engine Coolant Level Shutdown
C-10, C-12, C-15 and C-16 Industrial Engines E057 Low Engine Coolant Level Derate
C-10, C-12, C-15 and C-16 Industrial Engines E095 Fuel Filter Restriction Warning
C13, C15, and C18 Tier 4 Final Engines Cylinder Head Valves
G3304B and G3306B Engines Engine - Clean
2004/05/01 New Operation for Painting Marine Engines {1000, 7581}
2004/05/01 New Special Instruction, REHS1709, "Installation of the Advanced Digital Engine Management (ADEM) III Control System on G3612 and G3616 Engines" Is Available {1050, 1250}
C11 and C13 Engines Electronic Unit Injector Mechanism
ES12F, UPS 1000S and UPS 1200S Uninterruptible Power Supplys Modem
C15 Petroleum Generator Set Engines Crankshaft Seals
3508B, 3512B, and 3516B High Displacement Generator Sets Circuit Breakers - Reset
C15 Petroleum Generator Set Engines Engine Oil Filter Base
C13, C15, and C18 Tier 4 Final Engines Engine Oil Filter Base
2004/05/01 Revised Special Instruction, REHS0385, "Installation Of The Hydraulic Actuator System (Hydrax System) on G3612 and G3616 Engines" Is Available {1050, 1250}
C9.3 Tier 4 Final Engines Air Lines
3512B Engine Before Starting Engine
C15 and C18 Industrial Engines Water Lines
Back to top
The names Caterpillar, John Deere, JD, JCB, Hyundai or any other original equipment manufacturers are registered trademarks of the respective original equipment manufacturers. All names, descriptions, numbers and symbols are used for reference purposes only.
CH-Part.com is in no way associated with any of the manufacturers we have listed. All manufacturer's names and descriptions are for reference only.