Technical Bulletins

Using WATCHDOG® products with mounting adapters

Using Mounting Adapters - The 1" NPT of the WATCHDOG® is directly related to the 1" level viewing area. When using mounting adapters less than the 1" NPT, it is important to realize that what is indicated in the WATCHDOG® sight may not be a true indication of the level in the bearing housing. This happens for one of two reasons:

  • Trapped Air
    When the oil level rises in the bearing housing, the internal diameter of the fitting allows air to become trapped in the upper portion of the WATCHDOG® surge chamber. Therefore, the level seen in the sight of the WATCHDOG® is possibly much lower than what is actually in the bearing housing (Fig. 1).
  • Trapped Fluid
    When the oil level is lowered in the bearing housing, the internal diameter of the fitting allows fluid to become trapped in the lower portion of the WATCHDOG® surge chamber. Therefore, the level seen in the sight of the WATCHDOG® is possibly much higher than what is actually in the bearing housing (Fig. 1)