Magnum GURU®

Price: Contact us for purchase info: (877) 379-8258

SKU: 470-001 Series - Type S 470-002 Series - Type T 470-003 Series - Type FL 470-004 Series - Type FL-GX 470-005 Series - Type FL/FL-GX

Notes: Available in 35°F or 40°F release temperatures.

Product Description

Magnum GURU® Product Sheet
Magnum GURU® Installation and Maintenance Instructions
GURU® Cap Color Table
Effect of Extreme Cold on the GURU®


  • Drains twice as fast as the standard GURU® Plug
  • Will not trip or dump while locomotive is running
  • Straight SAE threads and O-ring seals provide for easy field maintenance and testing
  • Easy installation
  • Completely mechanical – No electrical or air connections
  • Not affected by air flow or air temperature surrounding valve – releases only when cooling water reaches setpoint
  • Easy system refill
  • Models available to convert existing freeze protection
  • Slotted actuator feature prevents nuisance dumps when refilling cooling system with cold water
  • Unit automatically rearms after filling and reheating Actuator sensing surface is the only wetted part
  • Optional domed anti-tamper cap eliminates ability to tamper with the valve resetting stemAnti tamper cap


Design Features

  • Actuator sensing surface is the only wetted part
  • Design excludes cooling water chemicals and other debris from moving parts
  • Long service life: All moving parts are stainless steel
  • Available in modified 1-1/4” NPT tee or flanged tee body styles
  • Paint mask minimizes accidental paint-ins
  • Knob on cartridge for easy installation and removal even in awkward locations


  • Locomotive engine cooling systems
  • Stand-by diesel heating circulators
  • Back up protection in event of shutdown
  • On-board tanks and piping


The Magnum GURU® Plug is a higher discharge capacity version of the standard GURU® Plug. The Magnum GURU® Plug is a self-operating thermostatic drain valve that responds to engine coolant temperature and will pop open and drain when coolant reaches the setpoint (35°F or 40°F). This provides almost a full 1.2 inch bore to rapidly drain a locomotive before freeze damage can occur.

Resetting and rearming the Magnum GURU® Plug is easily accomplished by simply reheating the cartridge and utilizing our GURU® Flag and Clip or GURU® Flag and Key tool which prevent the GURU® Plug from triggering open again while refilling the cooling system with cold water.