In this video, I disassemble a Shurflo 4008 water pump to show where the check valve is located and how to replace it if damaged. The primary function of the check valve is to stop the back feeding of water when hooked to city water from filling up and overflowing the fresh water tank.
The check valve sometimes becomes stuck open if debris is lodged in it or hard water leaves mineral deposit buildup. Another possibility is damage from water left in the pump over winter, and a hard freeze occurs. There are also rubber O-rings that can wear out.
Check valve kits are usually available for most pumps and are relatively inexpensive and easy to change. Much cheaper than replacing the whole pump.
Parts Mentioned:
- Shurflo 4008 Check Valve
- Shurflo Pressure Switch
- Inline Sharkbite Check Valve
- Shurflo 4008 Water Pump
- Shurflo Accumulator Tank
Link to More LYRV Plumbing Related Videos
Source: RV Water Pump Check Valve Function and Replacement How-to – Shurflo 4008
