MERCURY 90HP FOURSTROKE OUTBOARD TILT/TRIM SYSTEM Leak

Trim Cylinder Seal Kit

This kit contains the specialized O-rings and high-pressure wiper seals located within the cylinder end caps. Over time, these elastomers lose their memory and fail to maintain a tight seal against the reciprocating ram, leading to external fluid loss. Replacing these seals restores the hydraulic integrity of the tilt/trim manifold.

Manual Release Valve O-Ring Kit

The manual release valve allows the motor to be tilted manually by bypassing the hydraulic pump; its internal O-rings are a frequent secondary leak point. If these seals fail due to compression set or corrosion in the valve bore, fluid will leak from the side of the trim manifold even when the rams are stationary.

Quicksilver Power Trim & Steering Fluid

A leak results in fluid loss and the introduction of air and potentially moisture into the closed hydraulic system. Replacing the fluid is necessary to prevent cavitation in the trim motor pump and to ensure proper lubrication of the internal valves following the installation of new seals.