Sterndrive

Sterndrive Service & Repair

What is a Sterndrive?

A sterndrive or outdrive is a form of marine propulsion which combines inboard power with an outboard drive. The engine sits just forward of the transom while the drive unit (outdrive or drive leg) lies outside the hull. The drive unit (outdrive) carries power from the inboard engine, typically mounted above the waterline, outboard through the transom and downward to the propeller below the waterline. The outdrive resembles the bottom half of an outboard motor and is composed of two sub-units: an upper containing a driveshaft connected through the transom to an engine which transmits power to a 90-degree-angle gearbox; and the lower containing a vertical driveshaft receiving power from the upper unit gearbox, transmitted through another 90-degree-angle gearbox to the propeller shaft. The boat is steered by pivoting the outdrive, as on an outboard motor; no rudder is needed. The outdrive can be matched with a variety of engines in the appropriate power range; upper and lower units can often be purchased separately to customize gear ratios and propeller RPM, and lower units are also available with counter-rotating gearing to provide balanced torque in dual-drive installations.* Left: A typical Mecruiser Sterndrive. *From – https://en.wikipedia.org/wiki/Sterndrive

Service List

Complete Engine and Drive Service for Mercruiser, Volvo Penta, and OMC:

  • Connect boat to flushing system
  • Check power steering fluid level
  • Check engine oil level
  • Check all belts and hoses for wear and alignment
  • Start engine and check all systems for operation
  • Check all gauges for proper operation
  • Perform ECU system scan
  • Check for trouble codes
  • Check shifter remote control for proper function
  • Inspect battery connections and charge if necessary
  • Check electrical switches and boat lighting for proper operation
  • Remove and replace engine oil
  • Remove and replace engine oil filter
  • Remove and replace spark plugs
  • Remove and replace distributor cap and distributor rotor if applicable
  • Remove and replace water separating fuel filter and all other fuel filters
  • Remove, replace and reinstall sea pump impeller
  • Check fuel system for leaks
  • Check exhaust system for leaks
  • Remove, clean flame arrestor/air filter and reinstall
  • Inspect overall rigging for safety
  • Inspect and remove propeller
  • Drain and replace outdrive gear lube
  • Remove outdrive, check engine/drive alignment
  • Check outdrive u-joints for wear and grease if applicable
  • Check gimbal housing for wear
  • Check gimbal bearing for wear and grease if applicable
  • Inspect driveshaft and coupler splines for wear
  • Inspect u-joint bellow, exhaust bellow, shift bellow and shift cable for wear or damage
  • Grease shaft on driveline system
  • Reinstall outdrive
  • Check trim cylinders for leaks
  • Check all fluid levels
  • Check engine mounts for tightness
  • Check trim tabs for proper operation
  • Start engine and check for leaks
  • Check shift operation
  • Check all systems for proper operation
  • Check carb/throttle body and adjust if necessary or applicable
  • Clear ECU codes if applicable and verify no codes return
  • Degrease bilge area and outdrive
  • Clean, inspect and grease propeller shaft
  • Reinstall propeller
  • Check engine oil level and top off as necessary
  • Reinstall all seats, bases, actuators and hatch if applicable
  • Turn off battery switch if applicable
  • Prepare boat for customer retrieval
  • Recover boat if necessary

Basic Service

  • Drain engine oil and remove oil flter
  • Install new engine oil filter and engine oil
  • Drain and refill sterndrive gearcase
  • Remove, replace and reinstall water pump impeller
  • Start engine and inspect

Engine Oil Service

  • Drain engine oil and remove oil filter
  • Install new engine oil filter and engine oil
  • Check fluid levels
  • Start engine and check for leaks
  • Degrease bilge area
  • Check engine oil level and top off as necessary

Sterndrive Only Service

  • Inspect and remove propeller
  • Drain and refill outdrive gearcase
  • Remove outdrive, check engine/drive alignment
  • Check u-joints for wear and grease if applicable
  • Check gimbal housing for wear
  • Check gimbal bearing for wear and grease if applicable
  • Inspect driveshaft and coupler splines for wear
  • Inspect u-joint bellow, exhaust bellow, shift bellow and shift cable for wear or damage
  • Reinstall outdrive
  • Check trim cylinders for leaks
  • Check trim pump fluid level
  • Start engine and check for leaks
  • Check shift operation
  • Clean, inspect and grease propeller shaft
  • Degrease outdrive
  • Reinstall propeller

Please note each boat is unique. Depending on your boat’s make, model, application, and/or style, each service will vary from one boat to the next. For more information, please contact shop management with questions directly about your particular application.