Do you want to know how your marine gearbox works? (ep 297)
19 July 2025 · 19 min · 5K views · Indonesia
What this video covers
Removing and rebuilding a marine gearbox requires systematic disassembly and careful management of internal components to ensure proper re-engagement of the clutch cone. On the 40-foot catamaran Learning By Doing, the owner removes the starboard engine's gearbox after experiencing a slipping reverse gear caused by a worn clutch cone.0:45 The removal process involves disconnecting the drive shaft coupling, exhaust pipe, coolant overflow, gear cable, and engine mounts, while supporting the engine sump with a piece of bamboo.2:14 Once removed, the gearbox is disassembled on a workbench by extracting the gear selector, adapter plate, and main end cap.5:58 The internal components, including the clutch shaft and drive cogs, must be stacked in precise order to facilitate reassembly.10:02 After replacing the fibrous-coated clutch cone, the housing is resealed with RTV gasket maker and tightened in a cross-pattern sequence to ensure even pressure on oil seals.13:48 Testing the unit in neutral, forward, and reverse before reinstallation confirms the repair.15:50 Maintaining an organised workspace and documenting the order of parts prevents mechanical errors during the rebuild.
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