How to Remove an Inboard Outboard Engineby Mike Schoonveld
Most maintenance and repairs to an inboard/outboard boat engine are performed with the motor mounted in the boat. Occasionally, it's impossible to make the needed repairs with the motor in place and the only alternative is to remove the motor from the boat. This is not as difficult as you might think if you have the right tools and equipment available. It involves disconnecting various components which link the motor to the boat or other systems, then lifting the motor out with a front loader or block and tackle.
Position the boat's gear shift lever in forward gear.
Remove the outdrive unit from the rear of the boat by disconnecting the tilt/trim cylinders, removing the nuts which connect the outdrive to the gimbal and then pulling the outdrive and driveshaft from the rear of the boat.
Remove the engine cover inside the boat and remove as much of the seats, sun platforms or other built in furnishings as possible to allow access to the motor from all sides and angles.
Disconnect the ground cable leading from the battery to the engine block.
Disconnect the main wiring harness connection. When this is done the motor should be completely disconnected from the electrical system.
Turn the fuel shut off valve between the fuel tank and motor to the off position.
Remove the gasoline line from the inlet side of the fuel/water separating filter by loosening the hose clamp with a flat screwdriver and then working the hose free from the hose barb.
Remove the throttle/shift mechanism from the engine by removing the bolts and nuts which secure it to the motor as well as disconnecting the linkage between it and the carburetor or throttle body.
Disconnect the rubber hose (or hoses if a V-6 or V-8 engine) from the exhaust manifold by loosening the hose clamp with a flat screwdriver and working the hose free from the nipple to which it was attached.
Disconnect the water intake hoses leading from the rear of the boat to the water pump. These can be disconnected either at the water pump or where they attach at the rear of the boat, which ever is more accessible.
Remove the outer motor mount nuts from the two motor mounts which hold the motor to the bottom of the boat and two motor mounts which hold the motor to the transom. Don't change the position of the nuts under the motor's mounting brackets since these are the engine alignment nuts. The motor should be completely disconnected from the boat at this time and ready to lift out.
Connect a chain to the engine lifting bracket on the top of the motor and to a front loader on a tractor which will be used to lift the motor up and away from the boat. If you are in a shop with an overhead chain hoist use that or even a block and tackle under a stout tree limb will suffice.
Lift the engine free slowly, keeping an eye out for any extraneous wires which might have been installed and still connected and watching to ensure none of the hoses or wires removed get caught as the motor is lifted.
- Once the motor is free, use this as an opportunity to clean and inspect the bottom of the boat, the motor mounts and other parts which are normally hidden or too remote to reach. Also check the bottom of the motor, the starter, oil pan and other parts. This is the perfect time to make sure everything down there is tight and in good repair.
Things You'll Need
- Ratchet wrench
- Assorted sockets
- Flat screwdriver
- Front loader
- Always check the engine alignment once the motor is reinstalled to ensure it lines up the gimbal bearing and drive shaft coupler perfectly before replacing the outdrive.
Mike Schoonveld has been writing since 1989 with magazine credits including "Outdoor Life," "Fur-Fish-Game," "The Rotarian" and numerous regional publications. Schoonveld earned a Master Captain License from the Coast Guard. He holds a Bachelor of Science in wildlife science from Purdue University.