CONTENT OF DIESEL ENGINE OILS.

DIESEL ENGINE OILS HAVE MORE SEVERE DEMANDS MADE ON THEM IN SERVICE THAN DO GASOLINE ENGINE OILS. TWO DIESEL COMBUSTION PRODUCTS THAT LEAD TO RAPID OIL DETERIORATION ARE CARBONACEOUS PARTICULATES AND NO2. BOTH THESE PRODUCTS ARE STRONGLY OPERATING MODE DEPENDANT, THEREFORE, TO SPECIFY AN OIL CHANGE INTERVAL BASED ON MILES TRAVELLED DOES NOT NECESSARILY ACCURATELY REFLECT THE CONDITION OF THE OIL BEING REPLACED. AN INEXPENSIVE, IN-SITU DEVICE FOR MONITORING THE IN-SERVICE STATE OF OILS IS DESIRABLE. THIS PROPOSAL IS FOR FUNDS TO EXPLORE THE USE OF LOW POWER, FAR INFRA-RED SYSTEMS FOR MONITORING OIL QUALITY. AT VISIBLE WAVELENGTHS, OIL APPEARS "BLACK" EVEN AFTER SHORT INTERVALS AND WITH LOW PERCENTAGE CARBON LEVELS. THE REASONS FOR THIS ARE PRIMARILY DUE TO THE RATIO OF OPTICAL WAVELENGTHS TO THE SIZE OF THE SUSPENDED CARBON IN THE OIL (EVEN WHEN PEPTIZED BY THE DISPERSANT). THEREFORE, VISIBLE LIGHT ABSORPTION CANNOT ACCURATELY MONITOR OIL QUALITY. IT IS NECESSARY TO CONSIDER WAVELENGTHS IN THE FAR INFRA-RED REGION OF THE SPECTRUM. A SYSTEM, AND METHOD OF RESEARCH, TO USE FAR INFRA-RED RADIATION TO MONITOR SUSPENDED CARBON AND DISPERSANT FAILURE IS PROPOSED. THE SYSTEM IS AN EXTENTION OF A FABRY-PEROT TYPE ETALON, EXCEPT NON-INTERFERING AND WITH OIL RATHER THAN AIR BETWEEN THE SURFACES.