Troubleshooting



PROBLEM

Slow component operation









Pump makes excessive noise









Fluid contains contamination










Bypass indicator always reads "Bypass"






Bypass indicator reads "Filter is clean"






Broken filter housing






Ruptured element








Filter indicator reads "Bypass" upon start-up

PROBABLE CAUSE

A) Restricted return filter


B) Improper size element


C) Restricted suction filter



A) Restricted suction filter (cavitation)

B) Loose filter housing cover (aeration)


C) Low fluid level (aeration)


A) Improper type of filter element



B) Plugged element

C) Filter change interval too long


A) Fluid viscosity too high


B) Broken spring or weak spring


C) Plugged element

A) No element installed

B) Ruptured element


C) Broken spring


A) Pressure too high



B) Shock pressures


A) Bypass not installed or stuck close

B) Pressure too high


C) Change interval too long


A) Oil viscosity high during cold start-up

B) Highly contaminated system (if new system has not been flushed, it's common to load a filter with dirt within minutes of initial start-up).



C) Filter bypass setting too low relative to filter pressure drop with a clean element installed (for given conditions)

POSSIBLE REMEDY

A) Check bypass of element. Replace element.

B) Replace element with proper size.

C) Check for high vacuum reading. Replace or clean filter element.

A) Check for high inlet volume; replace or clean element.

B) Check for loose mounting bolts on cover; check for and replace worn gasket cover.

C) Check fluid level in tank; refill to proper level with clean fluid.

A) Determine if the micron rating of element is correct for application; check for bypass condition.

B) Replace or clean element.

C) Decrease time between filter change period; add bypass indicators to filters.

A) Check for recommended fluid viscosity.

B) Remove and replace bypass spring.

C) Replace or clean element.

A) Install element.

B) Replace element; refer to ruptured element problem.

C) Remove and replace bypass spring.

A) Check for pressure surges and correct; check suitability of housing for application.

B) Install shock suppressor (accumulator). 

A) Check housing for installed bypass.

B) Check for broken spring or guide stem. Replace Bypass.

C) Check suitability of element for application.

A) Run system until it reaches normal operating temperature.

B) In new systems flush with low viscosity fluid at high velocities.  Replace filter element several times until fluid is cleaned up.  In existing systems consult specialist and replace filter element(s).

C) Select a higher bypass setting if available and if circuit conditions will permit.  Replace filter with a larger one with a lower pressure drop.