SHIM 0776063 - Caterpillar

... Antifreeze - Ethylene glycol provides freeze protection as well as increasing the boiling point of the coolant. Ethylene glycol also reduces the heat transfer capability of the coolant. The actual loss in ambient capability depends on many factors, however, the general rule is: The loss in ambient capability due to antifreeze is 1°C (1.8°F) for each 10 percent concentration up to 50 percent.
Concentrations above 50 percent cause even greater reductions in heat transfer loss.
... Altitude - All of Caterpillar's product performance curves, unless otherwise stated, are quoted at approximately 183 meters (600 feet) above sea level. Any change to this altitude must be taken into account.
The loss in ambient capability due to additional altitude above 183 meters (600 feet) is .3°C (.5°F) for each 61 meters (200 feet). Do not correct for altitude below 183 meters (600 feet).
Chart B shows the loss for various altitudes.
... Ten Percent Overload - If the unit is performing at 10 percent overload for emergency use, allow a 5.5°C (10°F) loss in ambient capability.
... Air Recirculation - Air recirculation can cause significant losses in ambient capability. Every effort should be made to minimize recirculation.
... Air Flow Restricting - Specific air flow restriction data can be obtained in the TIF microfiche. The maximum allowable restriction, measured in inches of water, will vary depending upon the specific fan and radiator configuration. This variable can have a substantial effect on system cooling capability and should be addressed as part of the sizing and/or troubleshooting procedures.
To determine actual ambient capability, subtract each value from the previous variables.
Part consist must be verified to determine correct fan size, fan speed/ration, radiator and engine performance specifications.The actual ambient capability is based on 100 percent load factor. Any reduction in average load factor would increase the ambient capability of the unit.
After sizing calculations have been performed, normal troubleshooting procedures are required.