Sentinel Shutdown Systems | Coolant Pressure Valve (CPV)

Crack Press. Open.50 PSI
Crack Press Close.75 PSI
Flow Resistance1 PSI
Inlet/Outlet Size1/4" NPTF
Coolant Port1/8" NPTF



Coolant Pressure Valve (CPV)

Sentinel Shutdown Systems

When an abnormal condition occurs in a diesel engine, a Sentinel protection system like a coolant pressure valve or CPV, automatically shuts it down or reduces RPMs by controlling the fuel supply. Sentinel systems are entirely mechanical and independent of electrical circuits which is desirable for explosive environments.


The Coolant Pressure Valve protects the engine against major failures in the cooling system such as hose breaks, low coolant supply, water pump failure, and loose belts. The Sentinel System Coolant Pressure Valve is effective on almost any diesel because it can be customized to match the specific operating characteristics of each engine. The unique piston design in the Master Control utilizes the engine fuel pressure to assist in closing the fuel valve. This allows the Master Control to be closed at a higher working oil pressure than its original low idle setting.


In most cases, any Sentinel Coolant Pressure Valve (CPV) will last as long as the equipment on which it is installed. The system has few moving parts and no direct metal wear. Racor uses the highest quality aluminum, brass, and stainless steel alloy and precision-machines the parts to 1/1,000 of an inch tolerance for a perfect fit. Inside, special Viton-quad rings on the main piston of the Master Control reflect more Racor quality. Each of these rings provides a double seal between the fuel section and the oil section of the system, assuring that fuel and oil cannot mix within the control itself.



• Low oil pressure
• Loss of coolant
• High oil temperature
• High coolant temperature
• High transmission temperature
• Loss of tail pump pressure on irrigation engines