I have been surprised in the past how different the properties of the various types of oil are and hope that one of our oil experts can give me some insight into the following. The facility where I work is required as a part of the maintenance contract to change the oil in several large compressors once every three months. A requirement laid down by some engineer long ago and which generates much head shaking on the part of those who change it out several times a year. The compressors don't run that often being they are redundant and are used principally to pressurize the fire sprinkler system and so on. The oil that is changed out seems to be virtually as clean coming out as is the new oil is going back in.
The oil used is Mobil Rarus 427. I don't claim to be an expert on the differences in oil and I am wondering if in a moderate climate such as western Washington where we have neither temperature extreme whether I could use it in my car. I have an 1980 Oldsmobile that I use as a work car. The body is good, it starts right up and runs fine giving me very little trouble but as I approach 300,000 miles it does use a quart of oil every 1,000 miles or so.
I don't want to be foolishly cheap but it is difficult to see what I believe to be perfectly good used oil stack up since no one is appointed to take it away, only to eventually have some frustrated mechanic throw it away. Particularily if in fact it is safe to use in an engine crankcase. I hesitate to use it in my precious tractors but if the risk is minimal I am tempted to try and use it on my old work car. Sheesh! If nothing else I'm tempted to mix a quart in with my gasoline once and awhile rather than see it wasted. Does anyone know whether it is risky to use it as crankcase motor oil? It does not give a viscosity number but is touted as being exceptionally good for piston rings and valves, designed for temperature extremes and is a quite expensive, ashless synthetic. Can someone give me some advice? Any help would be very appreciated.This following information is from the Mobil product site: The Mobil Rarus 400 Series is a line of premium performance ashless air compressor lubricants designed to meet the stringent requirements of the major compressor manufacturers. The Synthetic Alternative Synthetic lubricants can provide your business with quantifiable economic advantages in performance-demanding applications such as reciprocating compressors. Mobil synthetic reciprocating compressor oils feature low volatility, low carbon formation, and high oxidation stability. As a result, they provide measurable performance benefits over conventional premium mineral oil-based compressor oils. These benefits include: Reduced valve and ring land/groove deposits Reduced oil consumption Reduced potential for fires and explosions in discharge lines Exceptional air separation and low foaming tendencies Additionally, these innovative oils provide outstanding protection of crankcase components. The bottom line: using Mobil synthetic oils in your reciprocating compressor applications can help you achieve peak performance. Synthetics are conventionally reserved for equipment subjected to extreme high or low temperatures, frequent high loading and extended service intervals to avoid both equipment and oil degradation.
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