Oil Pressure Gauge

Why do you need an oil pressure gauge? Well, Oil pressure is a very important factor in determining the longevity of many internal combustion engines. Frederick Lanchester invented the forced lubrication system where an oil pump picks up the oil and forces it through oil galleries or drillings and then into the most highly stressed bearings, for example the main bearings, the big ends and the camshaft bearings. Other parts like the cam lobes and the cylinder walls will be lubricated by oil jets.

Making sure you have sufficient oil pressure will ensure that the metal of the rotating shaft or journal and the bearing shell won't ever touch. That way, wear will be limited to the initial starting up and shutting down. The oil pressure, when added to the rotation of the shaft, will also hydrodynamically center the journal.

So you can see why oil pressure gauges are important. An autometer oil pressure gauge is one of the most popular brands. You will find that you can select from a mechanical oil pressure gauge or a digital oil pressure gauge.

Want to know how to win free prizes?

Oil pressure will fall as the bearing clearance increases from wear and the oil pump reduces its efficiency from age. Ultimately it may not be sufficient to protect the bearings, particularly if the engine is "lugged" at a low rpm. Certain engines will include an oil pressure gauge that will show the pressure at any moment in time, but others will just have a warning light that will show only when the oil pressure is not sufficient. The sensor for either kind of gauge is typically placed around the oil filter of the engine, right after the oil pump.

Oil pressure will be higher when the engine is cold because of the increased viscosity of the oil, and will also increase with engine speed. Oil pressure will be lowest under a hot idling condition, and the minimum pressure that the manufacturer's tolerances allow is typically given at this point.

Oil pressure that is too high might indicate a filter that is blocked, a blocked oil gallery or even the wrong oil grade.

Certain oil pressure gauges, particularly on cars that are an older model, will have a label with the term druck or drucks.  But most cars that are a newer model will typically not have oil pressure gauges, but instead will have status lights, or might even label the gauge using a pictograph.