For a quick and effective field test of oil condition, utilize the following guide:

• A – Center Deposit Zone: Undispersed soot, becomes more black with increasing soot load. Becomes shiny/very dark indicating glycol contamination.

• B – Black Aureole Zone: Dispersant wall, outer limit of agglomerated soot travel. If inner spot has sharp periphery, water may be present.

• C – Diffusion Ring: Carbon will be carried into this area if good dispersion properties exist.

• D – Translucent: Color indicates oil oxidation (darker yellow).

A filter is the best line of defense to remove contaminants once they have entered the machine. Here are reasons why you should place filters on the warm side of oil coolers:

• Reduces pressure drop

• Extends filter life

• Extends cooler life (better heat transfer because its cleaner)