Check valve - Information
What does a check valve do
A check valve is a valve that does not allow flow to go back in the opposite direction.
A check valve is mounted on the fuel pump outlet to get the best function and protect against recirculation of fuel. Be sure to use a check valve that is suitable for your fuel pump. check the type of thread on your pump and select check valve after that. A hose-mounted valve can also be used.
A non-return valve can be used for air, fuel and oil, but then the construction often differs as each area has valves that can withstand different heat and pressure.
Example areas of use:
Staged activation of fuel pumps
When using two or more fuel pumps that do not run all the time but are activated as more fuel is required, a check-valve is mounted on these to prevent fuel from leaking out the back , -to the fuel tank and it harder for the primary pump to keep the pressure up.
Keep fuel in fuel rail
When the engine is switched off, fuel slowly flows back to the fuel tank and the fuel rial is draind on fuel. This introduces air into the fuel system and makes engine start difficult. With a non-return check valve installed, there is always fuel in the fuel rail and the engine easily starts.
The change to an aftermarket check valves (Full Flow) is made to obtain maximum flow in the fuel system. These are also flexible and adapted to be assembled with different types of fuel pumps.
Standard check valves do not flow like an aftermarket check valves do but they keep pressure up in the system long after fuel pumps are shut off. Together with the original fuel pressure regulator, the pressure can be maintained for several days in the fuel system.
Aftermarket / Full Flow
Unlike the original non-return check valve, an aftermarket valve is designed for better flow. Now high power can be achieved despite the use of check valves. However, the bigger construction will not keep pressure well after the pumps are turned off. The same applies to fuel pressure regulators that are significantly bigger than original.
- Fuel system: Components and assembly
- Fuel system: Common problems
- Choose the correct fuel injector
- Check valve - Information
- Compare Fuel injectors
- Different Type of Fuels [Gasoline or Ethanol?]
- Different types of fuel systems
- Fuel catch tank / Fuel surge tank
- Fuel cell
- Fuel filler
- Fuel filter
- Fuel pressure regulator
- Fuel pump
- Fuel Pump Hanger - Information
- Fuel rail
- Injector flow - Horsepower rating
- Injector size
- Tank ventilation