Used Coolant Filter Analysis

October 2013

Inadequate diesel engine cooling system protection can quickly lead to both cooling system and engine component failure. These failures will cost you money, not only to repair/replace the failed component(s), but in lost revenue from downtime while the equipment is being repaired. It is critical that proper cooling system maintenance practices be used to maintain optimum cooling system and engine component protection in your diesel engine.

As part of your cooling system maintenance program, it's a good idea to occasionally inspect a used coolant filter in an effort to detect potential problems. Close examination of a used coolant filter may help you to identify problems within your cooling system.

Here are a few things to look at that may help you identify those problems:

Figure 1    Plugged Filter (see Figure 1) – may be an indication of:
      Oil in the cooling system
      An excessive amount of Supplemental Coolant Additive (SCA) within the coolant
      Dirty water
      The presence of stop leak products

Figure 1    Rusty Filter (see Figure 2) – may be an indication of low levels of SCAs. This can plug
       the filter.

Figure 1    Rusty, Leaking Filter (see Figure 3) – indicates little or no corrosion protection in the
       cooling system.