Oil Pump Gasket 129120-35121

Function and technical context

This gasket acts as a sealing element in the support or flange-support of the oil pump, ensuring a hermetic seal between the joining surfaces and preventing lubricant leaks into the engine lubrication system. The oil pump is the component responsible for distributing the lubricant under pressure throughout all the internal passages of the engine, protecting bearings, camshafts and other moving parts from wear due to friction. If the gasket loses its sealing capacity, the oil can escape to the outside or not be maintained in the circuit at the necessary pressure, directly compromising the lubrication of the engine and causing severe damage in a very short time. This is a wear part that, despite its apparent simplicity, is critical for the integrity of the lubrication assembly in Yanmar engines of the 3JH, 3TN, 3TNE and 4TNE series.

When to replace this part?

The most common symptoms of deterioration of this gasket are the appearance of stains or traces of oil in the pump area, a drop in the oil pressure indicated on the pressure gauge or the low pressure warning light on the instrument panel. It is recommended that this gasket be inspected at each seasonal maintenance or whenever the oil pump is disassembled for any service, as the sealing material can warp or crack with repeated thermal cycles. Replacing it preventively during a scheduled inspection is much more economical than facing a breakdown due to loss of lubrication while sailing.