Johnson Vacuum Valve Siphon Breaker

Take good care of your engine

The Johnson Vacuum Valve Siphon Breaker is used as a cheap insurance against water intrusion in the motor caused by siphoning effects in the exhaust pipe. This valve is saltwater, freshwater and glycol mixture resistant and can take an ambient temperature less than 60 degC.

Installation
Install the vacuum valve at a minimum height of 400mm above the water line and as near the boat's centre as possible so that the minimum distance is kept even when the boat heaves. Make sure that the vacuum valve is installed higher than the exhaust valve and that the connecting pipe/hose slopes evenly downwards. Mount the valve under the cockpit bench or on the wall to avoid exposure to heat or heavy vibrations.

Johnson Vacuum Valve Siphon Breaker Features:

• Non corrosive
  
• Easy to install
  
• Does not leak
  
• High quality plastic
  

Johnson Vacuum Valve Siphon Breaker Specifications:

• Valve housing: PP
  
• Valve: Silicone rubber
  
• O-Ring - NBR (nitrile) rubber
  
• Screw: ASIS 316 stainless steel
  
• Fluid temp: Max +60 degC
  
• Fluids: Water (salt and freshwater), glycol mixture in appropriate concentration
  
• Valve: Opens at a pressure equivalent to 30-50mm WC
  

Note: Temperature limits - make sure that the ambient temperature never exceeds + 60°C. Provided that the ambient temperature is between +5°C and +60°C a normal lifetime can be expected. When the temperature is higher or lower, the valve’s lifetime will be reduced. The ventilation opening on the red cover guard should never be blocked