General Pump 90164100 Oil Seal EZ Series - 2432

Stops Costly Pump Oil Leaks in Minutes

The General Pump 90164100 is an OEM crankshaft oil seal engineered to stop oil leaks at the drive shaft of General Pump and Interpump pressure washer pumps. If your WW, E1, E2, or compatible EZ series pump is weeping oil from the crankcase, this is the correct replacement part - purpose-built to restore the factory seal and prevent further oil loss and internal damage.

A worn shaft oil seal is one of the most common failure points on triplex plunger pumps. Left unchecked, even a small leak starves bearings and connecting rods of lubrication, leading to overheating, accelerated wear, and potentially a full pump replacement. The 90164100 eliminates that risk.

By swapping in this single OEM component, you restore crankcase sealing integrity, reduce downtime, and extend the working life of your pump - all without the cost or complexity of a major rebuild.

Why You'll Love the General Pump 90164100 Oil Seal

This seal delivers measurable results where it matters most: keeping oil inside the crankcase and keeping your pump running.

• Reliable leak prevention – The 90164100 restores a tight barrier at the point where the drive shaft exits the crankcase. Its precision-fit lip rides against the shaft surface, stopping oil seepage that occurs when the original seal hardens, cracks, or loses spring tension over time.

• Protects expensive pump components – Proper sealing ensures the oil bath stays at the correct level, protecting bearings, the crankshaft, and connecting rods from running dry. General Pump troubleshooting documentation identifies a worn crankshaft oil seal as a primary cause of oil leaking in the area of the crankshaft.

• Fast, straightforward replacement – You can swap this seal using common hand tools - snap ring pliers, a correctly sized socket or seal driver, and basic cleaning supplies. No specialized jigs are required. Most experienced users complete the work in under an hour.

• OEM-fit assurance – Dimensions are matched to General Pump / Interpump specifications: 25 mm inner diameter, 62 mm outer diameter, and 10 mm width. This eliminates the guesswork and fitment risk that comes with generic oil seals.

• Lower repair cost vs. full pump replacement – The shaft oil seal is a designated wear item. Replacing it when it fails is a fraction of the cost of replacing bearings, a scored crankshaft, or the entire pump assembly.

What Makes This Oil Seal Different

Generic automotive-style oil seals may share similar dimensions, but they are not rated for the vibration levels, duty cycles, or oil types found inside a pressure washer pump crankcase. Using one is a gamble that often ends in a repeat leak - or worse, contamination of the oil bath.

• Designed for high-pressure pump environments – The 90164100 uses oil-resistant elastomer materials compatible with SAE 30 non-detergent crankcase oil and the operating temperatures typical of triplex plunger pumps running at speeds up to 1750 RPM. It is built to handle continuous shaft rotation, vibration, and oil splash without premature degradation.

• Exact fit for WW, E1, E2, and selected EZ series – The lip profile, inner diameter, and outer body match the original General Pump / Interpump shaft geometry and housing bore. This precise seating reduces the risk of cocking during installation and prevents the premature wear that comes from an undersized or oversized seal.

How It Works

A shaft oil seal - also called a radial lip seal - bridges the gap between the rotating drive shaft and the stationary crankcase housing. It is the single barrier responsible for keeping lubricating oil inside the crankcase while allowing the shaft to spin freely.

1. Seals around the drive shaft The flexible sealing lip makes continuous contact with the rotating shaft surface. A garter spring behind the lip maintains inward pressure, ensuring the seal stays tight even as the shaft moves at operating speed. The 90164100's 25 mm inner diameter is sized precisely for the shaft or shaft sleeve used in compatible General Pump models.

2. Holds crankcase oil inside The inner edge of the seal prevents lubricating oil - typically SAE 30 non-detergent oil - from migrating out through the shaft opening. This holds true even under the vibration and oil splash conditions found during normal pump operation. When the elastomer lip becomes stiff or brittle with age, leaks develop and oil begins pooling behind the crankcase.

3. Blocks outside contaminants The metal-reinforced outer body seats tightly in the housing bore, creating a secondary barrier that helps prevent water, dirt, and debris from entering the crankcase from the external environment. This protects bearing surfaces and the oil bath from contamination that would accelerate internal wear.

Product Details

Use this section as a quick reference when confirming part specifications before ordering or during installation.

• Type: Single crankshaft / drive shaft oil seal (radial lip seal) for pressure washer and triplex plunger pump applications.

• Material / Construction: Oil-resistant elastomer sealing lip (compatible with standard non-detergent pump crankcase oils) with a metal-reinforced outer body designed to resist deformation under operating temperatures and maintain shape in the housing bore.

• Dimensions / Specs: Inner diameter 25 mm × outer diameter 62 mm × width 10 mm. Always verify these measurements against your existing seal or the pump's service manual before ordering.

• Compatibility: Used in General Pump and Interpump WW, E1, and E2 series pumps. Also appears in ET series solid-shaft configurations (1750 RPM) and select EZ and TX series models including the EZ2545S, EZ3040S, TX1508S34, TX1512S17, TX1810S17, and TX1812S17. Confirm fitment via your pump's exploded parts diagram.

• Position in pump: Located on the drive side of the crankcase, where the crankshaft exits or passes through the rear housing. This is not a water-side seal - plunger rod packing, HP/LP water seals, and piston rod O-rings are separate components.

• Included in the package: One (1) shaft oil seal. Additional O-rings, gaskets, seal retainers, or support rings are sold separately or as part of a dedicated seal kit.

Who This Oil Seal Is For

If you are seeing fresh oil around the drive end of your pump, the 90164100 is likely the part you need. Here is who benefits most from keeping this seal on hand.

• Pressure washer owners with WW, E1, or E2 pumps – Homeowners, small contractors, and facility maintenance teams running belt-drive or direct-drive washers with these General Pump series. Oil pooling under the pump or misting near the pulley is a clear signal to act.

• Service technicians and repair shops – Professionals performing routine pump overhauls, preventive maintenance, or leak diagnosis on General Pump and Interpump units. Stocking the 90164100 means faster turnaround on common crankcase leak repairs.

• Equipment rental fleets and maintenance departments – Operations managers responsible for keeping multiple pressure washers in service. Oil seal failures are gradual - catching a small drip early and swapping the seal prevents bearing damage, costly downtime, and emergency repairs across the fleet.

Frequently Asked Questions

Which pumps use the General Pump 90164100 oil seal? The 90164100 is commonly used on General Pump and Interpump WW, E1, and E2 series pumps. It is also listed in official parts breakdowns for the ET series (solid shaft, 1750 RPM) and appears in supplier catalogs for select EZ and TX models such as the EZ2545S, EZ3040S, TX1508S34, and TX1812S17. Always confirm by checking the exploded parts diagram or model manual for your specific pump.

How do I know my shaft oil seal needs replacement? Look for fresh oil appearing under the pump or around the drive shaft exit. Other telltale signs include oil mist on the drive belt or pulley, visible wetness at the crankcase rear cover, or a crankcase oil level that drops below the red mark on the sight gauge between scheduled oil changes. General Pump troubleshooting documentation lists a worn or improperly installed shaft seal as the cause of oil leaking in the area of the crankshaft.

Can I replace this oil seal myself? Yes. Many pump owners handle this repair with basic hand tools: snap ring pliers to remove any retaining ring, a correctly sized socket or seal driver to seat the new seal evenly, and cleaning supplies for the bore and shaft. Remove the old seal, clean all surfaces, lightly oil the new seal lip, and press it squarely into the housing. The key is ensuring the shaft surface is smooth and free of scoring, and that the seal lip faces toward the oil. If you are uncomfortable disassembling the pump or aligning the seal, a professional service technician can complete the work quickly.

Do I need any other parts when changing the 90164100? While the pump is open, inspect the seal retainer, any O-rings or support rings behind the seal, the drain plug O-ring, and the oil sight glass gasket. If significant oil loss occurred before the repair, check bearing condition and the shaft surface for wear or scoring. Some users choose to combine a shaft seal change with a complete seal kit service during a major overhaul to address all potential leak points at once.

How often should the shaft oil seal be replaced? There is no fixed replacement interval published for the 90164100. Replacement is condition-based - swap it when leakage is observed or during a major pump overhaul. Pumps operating in dirty, wet, or high-hour environments may see faster seal wear. A quick visual inspection of the drive-side area during routine maintenance helps catch early signs of failure.

Is this the same as the water-side piston seals? No. The 90164100 is strictly an oil-side shaft seal that work to retain crankcase oil at the drive shaft opening. The high-pressure water seals around the plungers - including HP/LP packing and piston rod seals - are entirely separate components, typically sold in dedicated water seal kits. Confusing the two can lead to ordering the wrong part.

Ready to Restore Your Pump's Oil Seal?

A leaking shaft seal is a warning, not a death sentence. Replacing it with the General Pump 90164100 is the most direct way to stop oil loss, protect bearings and crankshaft components, and extend the service life of your WW, E1, E2, or applicable EZ series pump - without the expense of a full rebuild.

Contact the team at Barens today to confirm your pump model and ensure part number 90164100 is the right fit for your unit. Our experts are ready to help you cross-reference your pump's data tag with the exploded diagram in your service manual for a perfect match.