Marine Transmission Repair for Optimal Vessel Performance

Marine Gearbox and Transmission Repair in Long Beach and San Pedro

We do marine transmission repair on inboard boats, including V-drive and direct-drive layouts, at your slip, dock or storage yard from Marina del Rey to Newport Beach, or at our San Pedro shop. We find out why the gearbox slips, clunks, leaks or whines before we quote a repair.

What the work covers

Our inspection covers the drivetrain from the gearbox to the propeller shaft. We start with the simple causes, since they can feel like a failing gearbox:

• Fluid: the level, color and smell of the transmission fluid.
• Controls: the shift cable and the lever on the gearbox, which has to move fully into gear.
• Cooling: on gearboxes with an oil cooler, a leak can mix seawater into the fluid. See gearbox cooler cleaning and a pressure test.
• Between engine and shaft: the damper plate, the shaft coupling, the motor mounts and the prop shaft alignment, which all affect noise and vibration.

If the fault is inside the gearbox, such as worn clutches, bearings or seals, we quote the repair or an overhaul before any work is done. Parts are quoted with the job, and we test the boat in forward and reverse when the work is finished.

When to call

• The boat slips out of gear, or engages late
• Hard, clunky or noisy shifts
• Grinding or whining that changes with speed
• The engine revs up but the boat does not pick up speed
• A drip or puddle under the gearbox

Questions about boat transmission repair

What does milky transmission fluid mean?

Water has mixed with the fluid, often from a leaking cooler or a failed seal. Water wears bearings and clutches, so avoid running the boat until it is checked. Burnt-smelling fluid can point to overheating or slipping.

Does the gearbox have to come out of the boat?

Not for every job. Fluid, linkage and cooler work, and many seal jobs, can be done in place. Internal repairs such as clutches or bearings usually mean removing the gearbox, and we quote that before any work is done.

Book a visit: submit a ticket with the boat, where it is kept, the engine and gearbox make and model, and when the problem shows up, or call (213) 693-0224.

See also: boat engine rattle at idle is it the damper plate.

See also: boat engine rattle at idle is it the damper plate.