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Oil Cooling

The rugged and efficient OK cooling system is perfect for any oil or glycol cooling needs including trucks, off-highway construction vehicles, farm and forestry equipment, etc. It features a number of long-life, reversible EMP fans with brushless motors to keep the heat exchanger clean through years of harsh use.  Any of our custom oil cooler systems are available in 12V and 24V, with the potential for higher voltages. The control strategy can be configured as temperature control, PWM or CAN control, or simple on/off.

Brushless Electric Fans

All of our OK series coolers feature EMP fans. EMP’s fans are brushless, controllable, reversible, and built from a cast aluminum shroud that can withstand even the harshest environments.

Fans on temperature controlled OK models are speed controlled by the system controller based on fluid temperature feedback. This allows for optimal thermal management and little fluid temperature variation, while also helping to prevent heat exchanger clogging in dirty environments. Fan speed on PWM and J1939 CAN controlled models can be configured by the customer.

Temperature controlled OK models include an EMP Micro Thermal Management Controller (uTMC). The uTMC can receive inputs from sensors, or from the vehicle. It uses an advanced software algorithm to interpret inputs and provide optimal thermal control to the system. It also provides complete system diagnostics.

Heat exchangers on OK coolers are of bar/plate construction and fabricated from an aluminum alloy that has been proven through stringent testing to be superior to copper-brass construction in durability and efficiency, while also weighing less.

Temperature controlled OK models offer as an option an integrated wiring harness assembly that will not break down or degrade when exposed to petroleum based fluids and glycol. The harness is built using connectors and interface terminals that are IP69k rated waterproof and dustproof.

Air flow can be reversed periodically as a part of routine vehicle maintenance. This helps keep the heat exchanger cooling fins free of debris and functioning properly. Fan reverse can be controlled by a manual push button, as a timed event, or by ignition on.

OK coolers come in both 12 and 24-volt versions to allow for easy installation on most vehicles by eliminating the need for an auxiliary power circuit. Units are also available in both pusher and puller configurations to maximize mounting location adaptability. Control strategy and fan speed can be configured as variable-speed temperature control, custom-speed PWM or J1939 CAN control, or single-speed on/off. UL and CSA approved OK versions are available upon request.

Any engine power used for cooling is directly subtracted from the horsepower available for driving the wheels, hydraulics, PTOs, etc. The OK1 series of electrified coolers manage fluid temperature while consuming much less power than a system cooled by a belt-driven fan or hydraulic fan.

On temperature controlled OK system coolers, the system controller receives and interprets fluid temperature feedback and drives the fan as necessary to maintain an optimal fluid temperature. This eliminates overheating and overcooling due to changes in ambient temperature and cooling demand.

Our OK1 and OK2 coolers contain a built-in fluid bypass. The bypass is regulated by a 45 psi pressure valve. Its purpose is to protect the system from excessive fluid pressure differences across the heat exchanger.

EMP-Link and J1939 CAN versions allow two-way communication to support diagnostics. J1939 CAN communications support J1939 messages defined for Secondary OBD Devices.

The OK series of coolers can be controlled through the following communication protocols:

  • On-Off, J1939 CAN, PWM , EMP-Link (Proprietary LIN), Temp Sensor.
  • PWM version provides tach-out feedback (RPM).
    • Note: J1939 CAN integrated FiL-11 fans available. Interim solution requires use of TMC system controller. Temp Sensor also requires use of TMC.
Specifications - OK System Variations
TypeOK1OK2OK4OK6
Max Heat Rejection Rate40,000 Btu/h100,000 Btu/h115,000 Btu/h200,000 Btu/h
Overall Package Weight33 lbs75 lbs190 lbs275 lbs
Heat Exchanger MaterialAluminumAluminumAluminumAluminum
Shroud MaterialSteelSteelSteelSteel
Maximum Ambient Operating Temperature203° F203° F203° F203° F
Minimum Ambient Operating Temperature-40° F-40° F-40° F-40° F
Maximum Oil Temp266° F266° F266° F266° F
Fan ConfigurationPush or PullPush or PullPush or PullPush or Pull
Voltage12V
24V
12V
24V
12V
24V
12V
24V
Maximum Current25 Amps50 Amps100 Amps150 Amps
Maximum Power0.47 hp (12V)
0.94 hp (24V)
0.94 hp (12V)
1.88 hp (24V)
1.88 hp (12V)
3.76 hp (24V)
2.82 hp (12V)
5.64 hp (24V)
Maximum Fan Speed4000 RPM (12V)
4600 RPM (24V)
4000 RPM (12V)
4600 RPM (24V)
4000 RPM (12V)
4600 RPM (24V)
4000 RPM (12V)
4600 RPM (24V)
Maximum Continuous Operating Pressure230 psi230 psi220 psi220 psi
Maximum Oil Flow Rate45 gpm45 gpm22.5 gpm22.5 gpm
Control OptionsOn/Off
CAN/J1939
PWM
Thermistor
On/Off
CAN/J1939
PWM
Thermistor
On/Off
CAN/J1939
PWM
Thermistor
On/Off
CAN/J1939
PWM
Thermistor
Fuse Rating30 A
Internal Bypass Pressure Valve45 psi45 psiN/AN/A
SAE O-Ring Boss Port Size-16 (1 5/16"-12)-20 (1 5/8in-12)-16 (1 5/16"-12)-16 (1 5/16"-12)
Heat Exchanger Fluid Volume0.6 gal0.8 gal3.8 gal4.5 gal
Maximum Fluid Viscosity77.5 ft2/hr77.5 ft2/hr77.5 ft2/hr77.5 ft2/hr
Fan Reversal ControlPush Button
Timed
Ignition On
Push Button
Timed
Ignition On
Push Button
Timed
Ignition On
Push Button
Timed
Ignition On