Abstract: First and second latch mechanisms are provided that allow a boat operator to prevent the moveable and stationary portions of an outboard from moving relative to each other. This device can be used during shipping, transportation, or use of an outboard motor in conjunction with a sailboat in which the rudder of the sailboat is used for steering, and it is desirable to maintain the moveable and stationary portions of an outboard motor rigidly with respect to each other. A first latch mechanism is attached to the moveable portion of the outboard motor, and a second latch mechanism is attached to the stationary portion of an outboard motor. The second latch mechanism is rotatable to place a receptacle into a region where a locking device can retain it.

Abstract: An uplock assembly for an outboard motor tilt mechanism has a pair of brackets pivotally connected with an overcenter hinge. The uplock assembly has a lever that an operator uses to force the brackets into an in-line, end-to-end overcenter configuration in which a lower bracket supports against a horizontal support axle attached to the tilt mechanism and an upper bracket pushes against a swivel bracket of the tilt mechanism. The upper and lower brackets are sized so that the swivel bracket is pushed beyond its normal full up trailering position into a tight configuration in which the swivel bracket and motor are restrained from bouncing even under excessively rough transportation conditions. Preferably, the uplock assembly includes a lever guide member having a catch mechanism that secures the lever in a fixed position when the uplock assembly is engaged to support the outboard motor.

Abstract: A power driven vessel is able to accommodate various types of power drive. The power driven vessel includes a vessel main body, power drive having an engine and a driving unit, an attachment member for mounting the power drive thereon, an insert recess portion formed within the rear portion of vessel main body, and a bottom plate disposed on the insert recess portion. The attachment member is movable between an upper position and a lower position in the vessel, and is directly placed on the bottom plate and inserted in the insert recess portion when the attachment member is held in the lower position.

Abstract: An outboard motor powered by an engine positioned within a cowling is disclosed. The engine has a block with a cylinder head attached at one side, the block and cylinder head defining vertically arranged combustion chambers. Air intake runners extend from an intake plenum along one side of the engine to intake passages leading through the cylinder head to the combustion chambers. An exhaust system including an exhaust manifold extending from exhaust passages leading through the cylinder head from the combustion chambers is positioned on the side of the engine opposite the runners. A fuel pump is also positioned on the side of the engine with the exhaust system, and an alternator is positioned between the fuel pump and the exhaust system. The runners are separated in the vertical direction, with an oil filter or one or more other engine components positioned therebetween.

Abstract: A steering device for a motor attached to a boat which device includes an elongated steering arm having electrical means for starting and stopping the motor, the steering arm secured within a clutch mechanism wherein clutch sleeves are tightly rotatably mounted within a circular plate mounted on an internal shaft causing a drag on the steering arm when moved vertically positioning the steering arm at a desired position and where horizontal movement of the steering arm steers the boat.

Abstract: A stern mounted vertically adjustable propeller and rudder marine drive. The aft end of a propeller shaft, the propeller, the rudder and printle and a skeg are vertically moveable to adjust a boat's draft for use in the water and when trailering. A stern underwater slot in the boat hull and shaped to enhance water flow accommodates the propeller shaft which is driven by an inboard engine. As the propeller shaft passes through the hull slot it engages a flexible water seal mechanism which self adjusts or maintains itself in various up and downward positions; its pivotal point is common with the conterline pivotal point of a universal joint, which is attached to a drive shaft connected to the transmission of an inboard engine.

Abstract: Trim angle sensor transmission for a marine drive arranged between a drive input and a drive output. The transmission has a rotatable input member (22) being rotatable between the angular trim limits of a marine drive, and is connected to an input (31) of a rotational output sensor (30) for detecting an angle of rotation of the input member. The output sensor (30) has electrically rotational limits which are wider than the angular limits of trimming. The transmission has a planetary gear drive including an annulus (26), a sun wheel (29), at least one planet wheel (25) and a planet carrier (24). The annulus (26) is fixed, the input member (22) is connected to the planet carrier and the sun wheel is connected to the output sensor (30), in such a way that the planetary gear drive gives a multiplication of the trim input to the output sensor (30).

Abstract: Boat propeller drive unit, comprising a frame-like carrier (1) intended to be fixedly joined to a boat transom, and a propeller rig (4) which is suspended in a fork (13) for trim and tilting movement relative to the fork about a horizontal axis (a). The fork in turn is mounted in the carrier for pivoting about a vertical steering axis (b). A pair of hydraulically operated piston cylinder devices (18,20) are pivotally joined at opposite ends to the rig (4) and to the legs (12) of the fork.

Abstract: A small, compact electrically operated outboard motor for use with a very small watercraft. A substantial portion of the propulsion device for the outboard motor is intended to be submerged and is mounted for steering and tilt and trim movement. These movements are controlled as well as the speed and direction of rotation by a control lever and mounting arrangement that can be conveniently positioned within the hull of an associated watercraft.

Abstract: A wireless remote control for the trim/tilt of a boat propulsion system including a plurality of transmitters, each capable of generating a signal on two channels and a receiver control responsive to each of the two signals and capable of synthesizing a third control signal from the combination of the two signals.

Abstract: A reversible motor mount that can be attached to the gunnel on either side of a canoe is disclosed. The mount has a movable piece with a bracket to which said motor is clamped. The movable piece is locked in a first position when the motor mount is mounted on one side of the canoe and is locked in a second position when the motor mount is mounted on the other side of the canoe. No matter which side of the canoe said mount is attached to, and the movable piece is moved and locked in the appropriate position, and said motor is clamped to said bracket, the propulsion force from said motor when it is in operation will be downward and rearward.

Abstract: An outboard motor support for preventing damage from inadvertent pivoting of the motor during trailering is provided which includes a pair of spring-loaded locking pins for convenient placement and removal. The support is attached to the motor and boat without making modifications thereto and handles are affixed to the spring-loaded locking pins for easy manipulation. Two embodiments of the outboard motor support are provided to accommodate the different popular types of outboard motors.

Abstract: A marine stern drive includes a tilt/trim and lift adjustment mechanism which raises and lowers the drive while maintaining an established trim angle. The adjustment mechanism includes a parallelogram linkage system. An upper lever of the linkage system is defined in part by a pair of tilt and trim actuators which vary the length of the upper linkage to adjust the trim position of the stern drive and for tilt up. A lower lever of the linkage system is defined between two flexible couplings of a propulsion drive train. One of the flexible couplings is coupled to a lower drive unit of the stern drive which permits the lower lever to rotate without changing the trim angle of the lower drive unit.

Abstract: A lift arrangement for a marine engine permits the output shaft of the engine to be vertically oriented when lifting the engine. The engine configuration results in a center of gravity located along a vertical axis which passes through a flywheel assembly of the engine. The flywheel assembly sits above an upper end of the engine block. The lift arrangement includes a pair of hangers mounted to the top end of the engine with the flywheel assembly positioned generally therebetween. The hangers are attached on opposite sides of a central, longitudinal plane of the engine. The hangers also are arranged such that a line between the hangers intersects the central, longitudinal plane at a point proximate to the vertical axis which passes through the center of gravity of said engine. With a cable connected to each hanger, the engine can hang by the cable from a lift with its output shaft vertically oriented, without removing or interfering with the flywheel assembly.

Abstract: The invention provides a device for stabilizing an outboard motor during transport in two embodiments. A first preferred embodiment includes a rigid block which is pivotally mounted from a bracket so as to be adjacent to a yoke which connects between the push rod end of a steering cable and a link to the outboard motor. The block has a hole in a position to enable engagement of an extended bolt on the yoke and can be pivoted to cause such engagement. In the engaged position, a wing nut is tightened to hold the block in position over the bolt, thus preventing movement of the outboard motor.In the second embodiment, a split block is provided of a material possessing a highly frictional surface. The split block has a hole with a split to an outer surface and is permanently mounted with a push rod of the steering cable extending through the hole.

Abstract: A method and apparatus for stowing and unstowing an engine in a dinghy. The apparatus includes a bracket to which the engine is attached. The bracket is pivotally attached to the transom of the dinghy through a transfer plate having two substantially perpendicular horizontal pivotal axes. As installed in the dinghy, the pivotal axes are substantially horizontal when the engine is in its operative position over the dinghy transom. To stow the engine, a handle on the bracket is lifted about a first of the two pivotal axes until the engine clears the transom. The bracket is then pivoted forward about its second pivotal axis until the bracket can be attached to a surface in the dinghy. The engine is thereby stowed in a first storage attitude. The entire dinghy, with stowed engine, can then be stowed out of the water on a second boat by rotating the dinghy about an axis that is parallel to the dinghy's longitudinal axis.

Abstract: An engine rotational number controller includes an engine rotational number detector 5 for detecting the number of rotation of an engine, a throttle opening detector 7 for detecting a throttle opening of the engine, an ignition device 11, a stepping motor 15, an injector 16, and a control circuit 4 for delaying an ignition timing of the ignition device 11 when the number of rotation of the engine becomes higher than a predetermined upper limit in the case where the throttle number is constant and for opening a sub-throttle valve 14 of a throttle valve 12 by means of the stepping motor 15 to increase an amount of intake air and to increase an amount of injected fuel in the injector 16 when the number of rotation of the engine becomes lower than a predetermined lower limit in the case where the throttle opening is constant.

Abstract: A steering and speed control mechanism is disclosed for a hand-controlled trolling motor. The mechanism includes a yoke assembly having a first section attached to the trolling motor and a second section hingedly attached to the first section. There is a control arm extension, which includes an axially rotatable shaft that carries a handle. A tubular receptacle operably engages the control arm of the trolling motor. A universal joint pivotably interconnects the receptacle and the shaft. A tubular sleeve interconnects the shaft to the second section of the yoke assembly such that the shaft is pivotable and axially rotatable relative to the second section of the yoke assembly. The trolling motor control arm is operated through the control arm extension to control steering and speed of the trolling motor.

Abstract: An outboard motor incorporating a unitary mounting assembly for resiliently connecting the steering shaft to the driveshaft housing. The mounting assembly also closes an upper portion of the driveshaft housing and has an opening that passes a water tube for supplying cooling water to the engine of the outboard motor.

Abstract: A throttle and transmission control assembly adapted to be mounted on the tiller of an outboard motor for controlling its transmission and throttle. Both the transmission and throttle controls employ devices that convert rotary into reciprocating motion and which amplify the reciprocating motion so as to permit a compact assembly. The movable components are all mounted on a single piece of the assembly so as to minimize manufacturing variations and to simplify the overall construction. In addition, an interlock is provided that controls the maximum speed at which the engine can be operated when in neutral and for blocking shifting into neutral from forward or reverse when operating at a greater than a predetermined speed but for permitting forced movement into neutral under some engine speeds and, at the same time, reducing the engine speed to the maximum permitted at neutral upon such shifting.

Abstract: A jet propelled watercraft having an outboard motor type of jet propulsion unit. The jet propulsion unit is disposed in substantial part forwardly of the transom and beneath the undersurface of the hull for improving its pumping efficiency. The jet propulsion unit is driven by a transmission including a drive shaft having a pivotal joint. The jet propulsion unit is pivotal relative to the engine about an axis containing the axis of the universal joint so that the water inlet opening may be swung upwardly through an opening in the undersurface of the hull which is above the water level for clearing foreign objects from the jet propulsion unit water inlet opening.

Abstract: A trailer for transporting boats including a hitch, a frame including a pair of parallel side rails, a cradle and an axle with wheels, the improvement comprising a rear cross member with arms that will rotate about a bolt in the frame and drop down for unloading or loading a boat. In the raised position a support arm is attached to the cross member and may be elevated to engage the final drive area of an outboard motor in a yoke fixed to the end of the support arm.

Abstract: A trim pin arrangement for an outboard motor wherein the trim pin apertures are disposed so as to extend substantially in a straight line to make the bracket more compact and also so that the trim pin will engage the swivel bracket at a different location depending upon which aperture it is received in so as to make more uniform the wear on the swivel bracket.

Abstract: Boat propulsion unit comprising a suspension arrangement (2) and a propeller drive shaft housing (3) which, via a lower and an upper universal joint (22, 24, respectively), are pivotally connected to each other. The suspension arrangement comprises a frame (5) in the form of an extruded aluminum profile which is fixed around an opening in a boat transom, and a carrier (6) attached to the frame member, the carrier covering the opening and supporting the pivot connection. The carrier is integrally formed with a flywheel casing (20) for a connected engine.

Abstract: A submarine propulsion system for a submersible vehicle has two motors mounted on respective support arms able to rotate about two axes relative to the submersible vehicle. Rotation of each arm about its first axis moves its respective motor out of a storage recess, in which it is stored when not in use, into an operating position and rotation of the same arm about the other axis moves its respective motor between two operating positions in which it generates vertical and horizontal thrust respectively.

Abstract: A low cost and easily mounted and removed electric trolling motor mount with optional fixed rudder is provided comprised of a structured bar with two slidable adjustable clamp assemblies to affix the mount to the gunwales of a boat. The optional fixed rudder is provided with torsional pivot means to allow the fixed rudder to move upwardly should the fixed rudder strike an object below the hull of the boat.

Abstract: Disclosed herein is an outboard motor including a fore and aft center plane and comprising a powerhead assembly including a two stroke internal combustion engine including a cylinder block including a port side, a starboard side, a plurality of vertically aligned cylinders in a single bank, which cylinders each include an axis extending at an angle to said center plane and to one of said port and starboard sides, and an exhaust port on the other of said port and starboard sides, and an exhaust gas passage including a main portion extending vertically adjacent said center plane, and a like plurality of elbow portions connecting said exhaust ports to said main portion, which elbow portions include any one change in direction.

Abstract: A piece of hull of a boat, vessel or other construction designed to travel over water, which piece is attached with devices to the rest of the hull in a manner that allows the pieces of hull to move relative to each other. The piece of hull is located partly or in its entirety in the bow half of the hull combination and includes at least an engine, a power transmission mechanism and a propeller or an impeller. The piece of hull according to the invention aims at minimizing as many of the negative features of boats provided with an engine as possible, such as the noise and vibrations caused by the engine, power transmission mechanism, and propeller, the shocks and violent movements caused by the action of the waves, the overturning effect of the headwind and the waves, frictional resistance, uncomfortable travelling position at low speeds, high threshold of planing, and poor steerability at low speeds.

Abstract: The present invention is an auxiliary steering handle apparatus adaptable to most boat mounted trolling motors. The apparatus is comprised of two main components, the pivotal telescopic handle or lever and a split gear housing or case. The pivotal handle or lever is both rotatable and telescopically extendable. Bevel and pinion gears are provided, with the bevel gear split into two halves for clamp mounting to the rotatable steering column of an existing electric trolling motor. Manual rotation of the handle facilitates rotation of the pinion gear and bevel gear, thus axial rotation of the motor is achieved in a full 360 continuous or by-directional rotation. Electrical commutation located within the case and lever, provides sliding electrical contact between a battery and the electric trolling motor.

Abstract: A number of embodiments of watercraft having jet propulsion units contained within a tunnel in the hull and wherein the jet propulsion unit is pivotal about a first transversely extending horizontal pivot axis for bringing the jet propulsion unit through trim adjusted positions to an upward out of the water position. In addition, the jet propulsion unit is rotatable about a horizontal longitudinally extending axis so that its downwardly facing water inlet portion may be rotated upwardly for access through an access opening in the hull for servicing. In one embodiment, the jet propulsion unit is only rotatable about the horizontal longitudinally extending axis. A number of embodiments of rudder assemblies are also depicted supported by the steering nozzle for generating steering effects when the steering nozzle is not generating a significant steering effect and which may be pivoted to an out of the water position for protection when underwater obstacles are struck.

Abstract: A main propulsion arrangement for a high power ship or the like comprises an underwater drive unit connected to and turnable by a substantially vertical tubular shaft journalled in the ship. The drive unit and the tubular shaft define a hollow casing enclosing an electrical propulsion motor connected to a propeller shaft, which is connected to a driving propeller external of the casing. The casing is, at its inside, supported by several mainly vertical web plates, which are arranged to act, in combination, as elements structurally stiffening and supporting the casing, as elements securing the propulsion motor in place relative to the casing, as elements transmitting to the casing reaction forces to the torque developed by the propulsion motor, and as wall elements of ducts for incoming and outgoing gaseous coolant for the propulsion motor.

Abstract: A number of embodiments of hull arrangements for watercraft that permit forward positioning of the propulsion device but also permit the hull to be constructed as a planing hull. In some embodiments, jet propulsion devices are disclosed and in another embodiment an outboard motor propulsion device is shown.

Abstract: A kit, an assembly and the combination of these with a boat's stern drive unit for the purpose of extending the propeller rearwardly of the boat to increase the trim height adjustment range and leverage. The kit and the assembly include an extruded spacer and an extension shaft.

Abstract: A folding transom for a boat having a trolling motor. The folding transom having an "engaged position" and a "retracted position". The transom including a motor mounting bracket, a pair of parallel horizontal legs, having first and second ends, each leg being attachable to a boat at the first end, a pair of "L" shaped members, maintained in parallel relationship, each of which is rotatably attached at one end of the "L" shaped member to the second end of a horizontal leg by a thumb screw for locking the "L" shaped member into an engaged position and on the other end of the "L" shaped member to the motor mounting bracket.

Abstract: A tiller arm and steering bracket assembly where the tiller arm is pivotally coupled to the steering bracket such that it can be selectively positioned in either a generally horizontal position or a generally vertical position. The tiller arm includes an underside having interference ribs that contact the steering bracket when the tiller arm is placed in the horizontal position. The interference ribs each have a retaining ledge that supports the tiller arm on the head portion of the steering bracket in an upright position substantially perpendicular to the steering bracket when it is placed in the vertical position. The steering bracket has integral crest formations which contact the retaining ledges to provide additional support to the tiller arm when it is placed in the vertical position. A bore formed through the steering bracket accepts a retaining pin that contacts the tiller arm at a point which prevents the tiller arm from unintentionally returning to the horizontal position.

Abstract: An outboard motor having a power head in which an exhaust expansion chamber is provided that receives the exhaust gases from the engine and delivers them to an underwater exhaust gas discharge. The expansion chamber is affixed to the engine and forms at least in part a closure for an exhaust manifold formed integrally in the engine cylinder block.

Abstract: An outboard motor for mounting on the transom of a boat, has a horizontal engine and output shaft, an exhaust system having a high speed exhaust discharge includes a horizontal portion and a vertical portion having an enlarged cross sectional water jacketed muffler within a water chamber having a retaining wall defining the water level, and a low speed exhaust discharge extending from the muffler into a conduit having an end disposed below the water level of said water chamber, a low speed exhaust gas expansion chamber receiving exhaust gas and expelling same to the atmosphere. The outboard motor is tiltable and provides an enclosure for the engine area including a cowling, hood, and moveable hood section and a sleeve between the moveable hood and engine to perfect enclosure during tilting.

Abstract: A displacement ship having a hull, a stern 6 which at least in the region of the underwater body form a flat surface to which the longitudinal axis of the ship is a normal, the hull at least in the region of the underwater body, narrowing towards the stern 6 neither with the side surfaces 1a, 1b nor with the bottom 1c.

Abstract: A number of embodiments of watercraft having jet propulsion units contained within a tunnel in the hull and wherein the jet propulsion unit is pivotal about a first transversely extending horizontal pivot axis for bringing the jet propulsion unit through trim adjusted positions to an upward out of the water position. In addition, the jet propulsion unit is rotatable about a horizontal longitudinally extending axis so that its downwardly facing water inlet portion may be rotated upwardly for access through an access opening in the hull for servicing. In one embodiment, the jet propulsion unit is only rotatable about the horizontal longitudinally extending axis. A number of embodiments of rudder assemblies are also depicted supported by the steering nozzle for generating steering effects when the steering nozzle is not generating a significant steering effect and which may be pivoted to an out of the water position for protection when underwater obstacles are struck.

Abstract: A remote control tiller arm is provided for controlling the operation of an outboard motor. An inverted U-shaped steering boom is attached to the outboard motor and extends over-the motor boat operator. The steering boom includes a throttle mechanism for remotely controlling the speed of the outboard motor. By using the steering boom, the motor board operator can steer the boat from a forward looking position.

Abstract: A watercraft having a jet propulsion unit that is supported at least in part within a tunnel on the under side of the hull and which is movable between a driving position and a service position. The control for operating the jet propulsion unit to move it between its positions is disposed within the tunnel and accessible through a service opening so that it cannot be accidentally actuated.

Abstract: A system is provided for deploying a propulsor unit from the hull of a water vehicle, such as a submarine. The system comprises an opening in a submerged portion of the hull that leads to a chamber for storing the propulsor unit, a cover for covering the hull opening to render the surface of the hull substantially continuous and fluid-dynamic, the cover having first and second sides, each of which conforms to the contour of the hull and the propulsor unit being mounted on the second side of the cover, and a pivotal mounting that hingedly connects the cover and the propulsor unit attached thereto across the opening in the hull for allowing the propulsor unit to move from a first stored position within the storage chamber to a second deployed position in the ambient water surrounding the hull. A drive assembly is provided for pivotally moving the cover and its attached propulsor unit between stored and deployed positions.

Abstract: A number of embodiments of watercraft having jet propulsion units contained within a tunnel in the hull and wherein the jet propulsion unit is pivotal about a first transversely extending horizontal pivot axis for bringing the jet propulsion unit through trim adjusted positions to an upward out of the water position. In addition, the jet propulsion unit is rotatable about a horizontal longitudinally extending axis so that its downwardly facing water inlet portion may be rotated upwardly for access through an access opening in the hull for servicing. In one embodiment, the jet propulsion unit is only rotatable about the horizontal longitudinally extending axis. A number of embodiments of rudder assemblies are also depicted supported by the steering nozzle for generating steering effects when the steering nozzle is not generating a significant steering effect and which may be pivoted to an out of the water position for protection when underwater obstacles are struck.

Abstract: A submersible thrust producing implement for use in combination with an excavator, the excavator being of the type having a boom and a stick with an attachment end on the stick for attaching the implement, which boom and stick can be extended and retracted to selectively submerge the attachment end to a predetermined location in a body of water, and having a hydraulic power system for actuating the boom, the stick, and the implement.

Abstract: A power steering system for an outboard motor for steering an outboard motor disposed outside of a rear portion of a hull and usually including a manual steering system mounted upon the hull for operating a steering element so as to manually steer the outboard motor body, is disclosed. A power unit is operatively connected to the manual steering system and includes an electric motor for applying a steering assist force to the manual steering system. The power unit is located at the portion of the hull capable of effectively utilizing the inner space of the hull and the electric motor of the power unit is controlled by means of a control unit in accordance with the navigation conditions of the hull and the operating conditions of the outboard motor as detected by means of suitable sensors. The sensors comprise various sensors such as, for example, a steering torque sensor and an engine speed sensor.

Abstract: A power steering system of an outboard motor to be mounted upon the body of a hull and including a steering bracket secured to the body of the hull, a swivel bracket rotatable about a body of the outboard motor and a pair of clamping brackets supporting the swivel bracket, comprises a manual steering unit for manually steering a steering element so as to operate the outboard motor, the manual steering unit including a link mechanism connected to the steering element and connected to the steering bracket, and a power unit operatively connected to the link mechanism of the manual steering unit. The power unit includes an electric motor for applying a steering assist force to the manual steering unit for reducing the steering load during steering operations through means of the link mechanism and also includes a mechanism for converting rotation of the electric motor into linear motion.

Abstract: A drive for a boat has a propeller hub rotatable about a main axis extending in a normal travel direction, a plurality of blades projecting generally radially of the main axis from the hub and each pivotal so as to be of variable pitch, and respective blade rods extending axially and displaceable axially relative to the hub to vary the pitch of the blades. A stator carried on the boat downstream in the direction from the hub and nonrotatable about the axis rotatably supports a cylinder housing that is releasably connected to the rods for joint axial movement therewith. A piston displaceable along the axis in the cylinder is releasably connected to the hub for joint axial movement therewith. Pressurizable lines extending through the stator are connected to the cylinder for alternately pressurizing the piston and thereby relatively axially shifting the rods and hub.

Abstract: An assembly for rotatably supporting the propulsion unit of an inboard/outboard marine propulsion system of a watercraft is disclosed. The watercraft includes an engine mounted therein which is drivingly connected to the propulsion unit through a through-hole formed in the transom of the watercraft. The support assembly includes a first bearing arrangement for rotatably supporting the drive from the engine to the propulsion unit and a second, concentrically mounted bearing arrangement for rotatably supporting the propulsion unit relative to the transom. The concentric bearing arrangement permits the propulsion unit to be rotated between above-water and in-water positions while minimizing the length of the propulsion system, thereby conserving space and allowing the propulsion unit to be more compact.

Abstract: A conduit arrangement in a hydraulic tilting system for an outboard drive unit wherein a plurality of connecting members are provided, one mounted at the lower end of the gimbal housing and two mounted on the outer periphery of the gimbal housing higher than the upper connecting member but lower than the tilt shaft on the gimbal ring. A pair of inboard conduits extend from a pressure source within the hull of the associated marine vessel to the lower connecting member while two pairs of intermediate conduits interconnect the lower connecting member with a respective one of the upper connecting members. There are two pairs of outboard conduits, each pair interconnecting one of the upper connecting members with a respective one of a pair of fluid motors which extend between the gimbal ring and the outdrive portion of the drive unit for effecting tilting and trimming movement of the outdrive.

Abstract: A control for adjusting the trim of a motor boat having a drive unit mounted on the boat for adjustment of the thrust angle relative to the boat. A trim motor adjusts the drive unit relative to the boat. A boat speed responsive pick up and control provides an output signal indicative of boat speed. A microprocessor controls the trim motor and is connected to receive the speed signals. The microprocessor reads boat speed at intervals and compares the latest speed reading with the prior reading to determine whether boat speed is increasing. The microprocessor commands the trim motor to move the drive unit in increments in one direction so long as each adjustment results in increasing speed and then to move the trim motor to adjust the drive unit in increments in the opposite direction so long as the adjustment results in increasing speed.