Instructions for the Cooling System and Antifreeze Use of Cummins Generator Sets

Instructions for the Use of the Cooling System

 

I. Cooling Methods of the Water Tank Radiator

 

Cummins diesel generator sets basically adopt a closed - loop liquid cooling method with a built - in fan. The circulation circuit of its cooling system basically consists of the following parts:

 

● Water pump;

● Water channels inside the engine cylinder block;

● Thermostat;

● Bypass pipe between the thermostat and the water pump;

● Water tank radiator;

● Pipes and hoses;

● Oil cooler;

● Coolant filter (available on some models). 

For non-standard generator sets, such as generator sets with a separate water tank, the water tank radiator should be replaced by a heat exchanger. At the same time, there are also components such as a supplementary water tank and a remote cooling fan. If the installation position of the remote cooling fan is relatively high, a transition water tank should be added to prevent the heat exchanger from being damaged due to excessive internal pressure.

 

 

Note: Various kinds of dirt adhering to the radiator chips will greatly reduce the cooling performance of the radiator. Therefore, in a dusty environment, it is very necessary to clean the radiator regularly.

II. Coolant

 

1. Coolant functions:

● Provide sufficient heat transfer capacity.

● Prevent corrosion (cavitation erosion) of all metal materials and sealing materials in the cooling system.

● Provide sufficient anti - freezing capacity.

 

Friendly reminder: Users are recommended to choose the Fleetguard coolant recommended by Cummins Inc. for better operation of the diesel generator. 

2. Selection methods

 

● The coolant should be a mixture of water and antifreeze or water and rust inhibitor. Among them, the pH value of water should be between 6 and 8. Generally, it is recommended to use pure water (distilled water).

 

● In areas with freezing conditions, antifreeze must be used in the coolant. The antifreeze capacity of this antifreeze must meet the extreme minimum temperature of the area. Users can select the antifreeze recommended by the engine and refer to the antifreeze usage (preparation) instructions. Mix the antifreeze evenly in a separate container and then add it to the water tank to ensure that the engine antifreeze does not freeze at low temperatures.

 

● Selecting a qualified brand of antifreeze recommended and approved by the engine is the key to ensuring the normal operation of the engine. The use of antifreeze not only prevents the engine from freezing but also raises the boiling point of the coolant at high temperatures (the water tank is less likely to boil over).

 

● In areas without the risk of freezing, a rust inhibitor can be used instead of antifreeze to achieve a better anti - rust effect for the metal parts inside the engine water pipes without reducing the cooling performance of the generator set. After the first filling of the rust inhibitor, the generator set should be run until it reaches the warm - up state to obtain the best anti - corrosion protection.

 

Note：The coolant should be replaced every two years to avoid a reduction in cooling performance due to sediment in the cooling system. Another reason for replacing the coolant is to avoid the risk of rust in the generator set. Over time, rust can impede the effective performance of the coolant and cause the water temperature sensor to malfunction.

  

3. Coolant replacement

 

● When replacing the coolant, the system should be flushed with clean water first. Make sure to continue flushing until the water coming out is very clean.

 

● When draining the coolant, ensure that the generator set is turned off and the engine body is completely cooled. Then open the water tank filler cap. Next, open the drain plug of the water tank and the drain plug on the engine body to drain the water. If the generator set is equipped with a coolant filter (available on some models), remove the filter and replace it.

 

 4. Coolant addition

 

● Before adding coolant to the coolant system, make sure that the drain plugs of the water tank and the engine body are tightly closed.

● Do not add coolant to the system too quickly to avoid the formation of air bubble gaps in the system.

● Air must be discharged through the filler opening and the exhaust valve on the engine body. If the cooling system is connected to a heater, the heater control valve must be opened, and ventilation inside the unit should be maintained during filling.

 

Note: The exhaust valve on the engine body is generally located at the highest point of the engine water circuit or near the thermostat and the water - temperature sensor. You can also exhaust air by slightly loosening the water - temperature sensor, and then tightening it after seeing coolant flowing out from there.

 

● When filling the coolant, the liquid level should reach 5 cm below the welding surface of the water tank (or the coolant level indicator scale line). Ensure that the generator set is shut down and completely cooled before adding coolant. Do not start the generator set until the system is ventilated and filled. After adding the coolant, start and pre - heat the generator set. At the same time, check the coolant level and add more if necessary. The same - specification coolant as the original cooling system should be added to the water tank.

● For some generator sets equipped with a coolant filter, open the filter valve (turn the handle to the vertical position) before putting the generator set into formal use.

 

III. Coolant Pre - heater

 

As an optional accessory, Cummins can provide users with two types of generator set pre - heaters for selection. The purpose of using a pre - heater is to ensure that the generator set can be started quickly in low - temperature conditions and during emergencies.

 

These two types of generator set pre - heaters are the AC - powered electric pre - heater and the DC - powered fuel - fired pre - heater. Both of them heat the generator set coolant to achieve a constant temperature (raise the temperature) of the engine body. The difference is that the former uses AC mains power as the energy source, while the latter uses the generator set fuel (diesel) as the heating energy. Users can choose the appropriate heater according to the usage environment and conditions.

 

The heaters supplied with Cummins diesel generator sets have been installed and commissioned before leaving the factory. Users only need to connect the relevant power supply (fuel) as required to put them into operation.