Hotsy Pump Oil (8.923-422.0) is a specially formulated High-Pressure Pump Oil exclusively designed, tested, and proven to maximize the life of Hotsy Pumps. This special formulated, premium-grade, oil contains an advanced additive package to protect against wear, oxidation, rust, and corrosion. Northstar Clean Concepts does not recommend the use of motor, transmission, hydraulic or compressor oils in pressure washer pumps.

Milky pump oil can be caused by condensation in the crankcase or seal wear. If the pump is allowed to run after the low-pressure seals and high-pressure seals have become worn, water may eventually travel back along the plunger rod and past the oil seal. Water is a contaminant to the crankcase oil and can cause damage to the drive-end components. The water will cause the oil color to change to a milky consistency initially and in severe situations can cause damage to the drive-end.

Crankcase oil should be changed after the initial 50-hour running period, then every 500 hours thereafter.