What is Oil Pumps?
The oil pump is an internal engine component, usually a gear or rotor type, driven by the crankshaft. It pressurizes oil and forces it through passages to lubricate bearings, pistons and the valve train.
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What it is
The oil pump is an internal engine component, usually a gear or rotor type, driven by the crankshaft. It pressurizes oil and forces it through passages to lubricate bearings, pistons and the valve train. An oil removal pump is a separate external tool, either manual or electric, that uses a thin tube to extract used oil through the dipstick tube. This makes oil changes easier in tight engine spaces without needing to reach the drain plug.
What it does
The engine’s oil pump maintains continuous pressure, typically between 40 and 60 psi (refer to your owners manual), pushing oil to all critical engine components. It draws oil from the sump through a pickup screen, pressurizes it and sends it through the filter before distributing it throughout the engine. An oil removal pump makes oil changes cleaner and easier by extracting old oil from above through the dipstick tube, which is especially valuable in boats where the oil pan is difficult to access.
Why it matters
Although rare, a failed internal oil pump causes an immediate loss of oil pressure and can destroy an engine within seconds. Low oil pressure from a worn pump can lead to bearing failure, piston seizure and complete engine failure. While an oil removal pump is not essential, it makes oil changes much easier, helping ensure they are done on schedule and preventing neglect that can damage the engine. On boats with hard-to-reach drain plugs, a removal pump can be the difference between regular maintenance and skipped oil changes.
General Maintenance
The internal oil pump rarely requires attention, but it is important to monitor the oil pressure gauge. Pressure should remain steady and within the manufacturer’s specifications. Investigate any drop in pressure immediately before continuing to run the engine. For oil removal pumps, keep the pickup tubes clean and inspect the seals annually for leaks. After each use, flush the pump with clean oil to prevent internal corrosion, and store it with the pump and lines drained to avoid oil degradation.
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