Replacement and cost of the fuel tank rollover safety valve

The fuel tank rollover safety valve is a brass or plastic valve located on the fuel tank.  The fuel tank rollover check valve works by way of a ball or spring inside that allows pressure and vapor to escape the fuel tank when changes in temperature occurs. The Ball in the valve moves to the closed position when the vehicle experiences a rollover; in effect cutting off fuel from exiting the tank. Most fuel tanks have a rollover valve of some kind. This article is regarding threaded brass rollover valves found in most diesel commercial trucks and auxiliary diesel tanks. The valve is threaded into an NPT bung fitting that has been welded into the tank or pushes into a grommet type seal. 

To replace the rollover safety valve:

1) Unhook the vent line from the hose fitting on the valve. 

2) Use a wrench to un-thread the valve from the bung fitting.

3) Properly dispose of the valve.

4) Prep the new valve by wrapping the threads with fuel save thread tape or use a thread sealer paste. make sure to put the thread tape on counter clockwise to prevent it from unraveling when you thread in the valve.

5) Thread in the valve clockwise in to the bung on the tank and tighten until tight.

6) Hook up the vent line hose and secure with clamp.

Here is a link to a selection of rollover safety valves in stock CLICK HERE 

Cost of replacing the rollover safety valve is between $9 to $60.00 depending on the application and materials the valve is made of.