What is the difference between power prime & spring prime piston distributors or injectors?
The firing and priming actions are reversed for the two types of Injectors or Piston Distributors. Spring-prime Injectors dispense their lubricant under rising main line pressure that overcomes their spring loaded metering piston and then reset (prime) when the spring returns the piston after the main line s pressure is vented. Pressure-prime Injectors reset (prime) when the main line pressure is rising and dispense their lubricant when the main line s pressure is vented, allowing a compressed spring to force the metering piston forward dispensing the lubricant.
