The designer's goal was to create a low maintenance device with long life capacity in extreme duty environments. To reach this end, we first decided the hydraulic pump had to be indestructible. After two years of testing, the clear winner was the Oildyne® 12 volt hydraulic pump and reservoir assembly (the same pump used on all Mercruiser® stern drive power trim systems).
The hydraulic hose is polyurethane jacketed high pressure line with DuPont® Kevlar™ braided winding to withstand the extreme operating pressures. Kevlar is the same material used in bulletproof vests. The hydraulic hose ends had to be simple, non-corrosive, and retrofitable in the field. We chose Aeroquip™ brass reusable fittings. We then have them nickel plated for appearance and to help separate them electrolytically from all aluminum components. Each hydraulic cylinder is capable of lifting 5,000 lbs, which is twice what is necessary even in the most demanding circumstance with the largest outboards. The Porta Bracket uses one of these cylinders per outboard motor. The cylinder is designed around existing products readily available in the marketplace. For example, the rod is constructed of durable 316 low carbon stainless steel in 1" diameter. The cylinder walls are 3/8" thick with a 2" diameter bore. This combination of dimensions facilitates the use of "O" rings and seals commonly available. Our goal being - the customer, regardless of location, is able to service the product without being held hostage by a company selling a proprietary product.
Our hinge design, however, is patented and proprietary. The extruded aluminum configuration uses UHMW (ultra high molecular weight) polyethylene bearing surfaces. This material has durability similar to nylon, with a lubricity built in approaching that of Teflon™ eliminating the need for owner applied lubricants. The bearing area is designed to distribute load and with a bearing surface area of over 200 square inches per engine. The interlocking hinge is assembled by sliding the male and female shaped extrusions together from the ends with the polyethylene bearing material. This step is performed using 4000 pounds of hydraulic pressure, creating a completed hinge that will never get sloppy and come apart. They are so tight they cannot be moved by hand and must be moved hydraulically. Four of the completed hinges make up a single engine bracket. We can boast that no one has ever worn out a hinge in 10 years of service - clearly a no maintenance part.