Use only SAE #30 engine oil . Avoid multi-grade oils (e.g., 10W40), as they can negatively impact the coefficient of friction and cause clutch slippage.

Ahead linings often show "gramophone groove" witness marks. Modern replacement linings require professional bonding.

The gearbox is typically attached to the engine bell housing by internal nuts. You must remove the gearbox and bell housing as a single unit.

A full overhaul requires specific replacement parts to ensure the integrity of the hydraulic seals and mechanical drive. Component Type Part Number / Requirement Seals the output shaft for direct drive units. Gasket Kit Includes essential O-rings for pressure integrity. Brake Pad Neutral brake pad for stopping shaft rotation. Oil Filter TM 12009 / 12773 Models differ between MK II and MK IV versions. Step-by-Step Workshop Procedures 1. Removal and Disengagement

Maintaining a marine transmission like the series requires technical precision and a deep understanding of its unique hydraulic and mechanical architecture. These gearboxes, originally produced by manufacturers like Thames Marine Propulsion and Henry Meadows, are heavy-duty units that demand specific procedures for overhaul and service. Essential Technical Specifications

During disassembly, pay close attention to the following high-wear areas:

Since the bell housing often carries the rear engine mounts, ensure the engine is properly supported before unbolting.

If the 8-bush input is seized due to rust, experts at Thamesway Marine Products suggest cutting a small access hole in the housing to apply lubricant and leverage the flywheel directly. 2. Inspection for Wear