Gunk! A Cry for Help

Maybe it's crud, munge, or simply a slimy residue. If you haven't seen any lately, you're lucky. Try looking in a pump strainer or fluid filter. Examine lubricated parts. Check air supply lines. You may have a problem.

Bad News:

  • Lubricating grease thickener separated in a set of bearings. The separation resulted in a mysterious gunk. This gunk failed to provide the required lubrication. Unfortunately, the manufacturer found it too late. The bearings seized.
  • A "gelatin-like" gunk under the valve cover of an engine was sugar.
  • A mysterious "gunk" found on circuit boards was determined to be solder flux which had evaporated, condensed in ventilation ducts, and dripped onto the boards during production.

Good News:

Gunk takes time to develop. Catching it early can save you thousands in product failures and production shutdowns.

Steps to Solving a Gunk Problem:

  1. Collect a Sample
    Use a clean instrument to collect the sample. Be careful not to introduce additional contaminants. Clean spoons or plastic coffee stirrers work fine. A "teaspoon full" is plenty.
  2. Have it analyzed
    Send the sample to your trusted laboratory. Be sure they are trained in problem-solving. You may need their help getting to the root of the problem.

    Confirm that they have "Micro FTIR" capabilities. This lets them identify traces of contamination. This is vital to catching your "gunk" problem while there's still time to resolve it.

  3. Discuss the results
    Be sure you get information that is meaningful to you!

    Work with your laboratory to understand what the results mean. If their report just gives a bunch of chemical terms, they're not giving you enough clues to solve the problem.

  4. Make changes
    With a little investigation and some teamwork, your gunk problem (and any related problems) can be licked.

The first step is recognizing you have a problem.

By Fred Hochgraf
Originally published in the NHML Nuts & Bolts Newsletter Vol. 2; Winter 1996




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