- The main bearing oil seal is a crucial component in the engine's lubrication system. It plays a vital role in preventing oil leakage from the engine's main bearings while allowing the rotation of the crankshaft. This dual functionality ensures the smooth operation of the engine and extends its service life.
Oil seals, also known as grease seals or shaft seals, are essential components in many machines and systems. They play a crucial role in preventing the leakage of oil and other lubricants, ensuring the smooth and efficient operation of various mechanical parts.
It is crucial to understand that oil seals, like any other mechanical component, are subject to failure over time. The key to minimizing downtime and enhancing operational efficiency is recognizing the signs of oil seal failure and understanding its reasons. Here are some common failure modes:
contaminated with moisture or any other particle. But the same oil will only last for a month at 212 degrees Fahrenheit if it’s contaminated with little water. This is why the function of an oil seal is very evident whenever it’s used.
Above, are all the components of an oil seal and all its naming conventions. Beyond selecting the correct size, the three primary selection criteria are Material, Lip, and Case. If you have an oil seal you’d like custom designed and made, send us your specifications through our Oil Seal Design Form.
1. Criteria for selecting oil seals


In conclusion, shaft oil seals are essential components in machinery and equipment that help to prevent leaks, protect critical components, and ensure smooth operation. Their importance cannot be overstated, and proper selection, installation, and maintenance are key to maximizing their effectiveness and prolonging their lifespan. With the right seals in place, machinery can operate efficiently and reliably, delivering optimal performance and productivity.
Of course, all rubber materials and seals will provide a range of benefits; however, you will need to consider chemical compatibility, sufficient temperature ranges, pressure ranges, and more.
The simplest way is to know either the preferred manufacturers part number, the overall sizes of shaft diameter, housing diameter and bore depth, or use our brochure to establish the M Barnwell Services ordering reference. Many of the old traditional names of seal manufacturers have either changed or disappeared in this age of “acquisitions”. If no longer available, we will advise you and offer a suitable alternative seal, from stock whenever possible. If your concern is getting the right seals for the job, you will need to know something about the application as well as the overall sizes. If you have any doubts – contact us, we will help in your seal selection.
• Fluorine rubber
Standard 3760/3761