{"product_id":"r-amp-d-flexible-shaft-coupling-f-5-b-w-hurth-amp-volvo-25hp-100rpm-capacity","title":"R \u0026amp; D Flexible Shaft Coupling f\/5\" B\/W, Hurth, \u0026amp; Volvo - 25HP\/100RPM Capacity","description":"\u003cp\u003e\u003cstrong\u003eFlexible Shaft Coupling for 5\" B\/W, Hurth, \u0026amp; Volvo - 25HP\/100RPM Capacity\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eThe R \u0026amp; D Marine Flexible Coupling consists of a flexible disc molded with a polyester elastomer. The disc gives clearance for bolt heads and is able to flex freely to take up any temporary misalignment of the engine and shaft due to flexing of the boat structure or the engine moving on its mount. Forward thrust is taken in compression on the disc between the two half couplings, and reverse thrust is retaken in compression on the disc between the two fail-safe straps. In the unlikely event of a severe impact, the steel straps make the coupling fail-safe and ensure the drive is maintained both forward and reverse.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eReduce Engine Noise \u0026amp; Transmission Vibration\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eStaggered bolts enable the element to isolate vibrations and compensate for some misalignment.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eReduces Costly Transmission Repairs\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eAbsorbs shock loads due to hard gear changes.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFits Most Major Transmissions\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eFor engines, 5 to 1,500 horsepower It fits brands such as Borg Warner, ZF-Hurth, Twin Disc, Volvo, Yanmar, Technodrive, and more.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eUnder Compression Load In Both Forward \u0026amp; Reverse\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eThe aft steel strap bolted to the transmission acts as a backing plate to prevent reverse thrust from pulling the element apart.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eQuick \u0026amp; Easy Installation\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eThe R \u0026amp; D Marine Flexible Coupling requires no machining and comes supplied with bolts to connect between the two existing shaft flanges.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eExtremely Durable\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eImpervious to saltwater, diesel, and lubrication oils. The Flexible Couplings are made from a polyester elastomer not affected by saltwater, diesel, or lubrication fluids.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFail-Safe Design\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eA fail-safe design is incorporated in the R \u0026amp; D Flexible Shaft Coupling that prevents the two couplings from pulling apart in the event of an impact or element failure, whereas other couplings do not. This fail-safe design is accomplished by using two steel straps and thru-bolts going into both the shaft coupling and transmission output flange. The aft steel strap is bolted to the transmission output flange, and the front strap is bolted to the shaft coupling. In the event of an impact, the aft steel strap (bolted to the transmission) will catch the front steel strap (bolted to the shaft coupling) and prevent the drivetrain from pulling apart.\u003c\/p\u003e\u003cp\u003eThe R \u0026amp; D element will absorb the shock load (reducing or eliminating damage to the transmission) and will maintain contact between the two couplings. The steel straps also keep the R \u0026amp; D Flex-Coupling under a compression load in both forward and reverse operation (the aft strap bolted to the transmission acts as a backing plate).\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eMachined Not Molded\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eThe Drivesaver is molded, while the R \u0026amp; D Flexible Shaft Coupling is machined. Both designs suggested that you first set your alignment by drawing the two couplings up to each other and then adding the flex-coupling. The machined part will have MUCH tighter tolerance than a molded part.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eChecking Alignment\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eThe R \u0026amp; D Flexible Shaft Coupling allows for alignment inspection after the element is bolted in place. There is one bolt head that is machined and painted red. After the R \u0026amp; D Flexible Shaft Coupling is bolted into place, a feeler gauge can be slipped between the red bolt head and the coupling. This process is repeated with the same bolt four times at 90-degree intervals by rotating the shaft. If the gap is within .010\" (0.25mm), the engine is accurately aligned.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eTo calculate the power of the coupling required:\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cu\u003eHorse Power of Engine\u003c\/u\u003e x Reduction Ratio x 100 = HP\/100RPM\u003cbr\u003e      Engine Speed  \u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eExample:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFord 150 HP at 2500 RPM with Borg Warner Velvet Drive 72C 2:1 Reduction Ratio\u003c\/li\u003e\n\u003cli\u003eEngine Horse Power is 150 HP, Max Rated RPM is 2500, Reduction Ratio is 2:1\u003c\/li\u003e\n\u003cli\u003e150\/2500 x 2 x 100 = 12 HP per 100RPM\u003c\/li\u003e\n\u003cli\u003eThe coupling required is 910-009\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eSpecifications:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eManufacturer: B\/W, Hurth, Volvo\u003c\/li\u003e\n\u003cli\u003eDiameter (inches\/mm): 5 \/ 127\u003c\/li\u003e\n\u003cli\u003e# of Bolts: 4\u003c\/li\u003e\n\u003cli\u003eDiameter of Holes (inches\/mm): 0.44 \/ 11.2\u003c\/li\u003e\n\u003cli\u003eBolt Pitch Circle (inches\/mm): 4.25 \/ 107.9\u003c\/li\u003e\n\u003cli\u003eRegister (inches\/mm): 2.5 \/ 63.5\u003c\/li\u003e\n\u003cli\u003eDiameter (inches\/mm): 5.63 \/ 143\u003c\/li\u003e\n\u003cli\u003eLength (inches\/mm): 2.06 \/ 52.4\u003c\/li\u003e\n\u003cli\u003eBolt Diameter: 7\/16 UNF\u003c\/li\u003e\n\u003cli\u003eHP per 100 RPM (hp \/ kW): 25 \/ 18.64\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"R \u0026 D MARINE","offers":[{"title":"Default Title","offer_id":63533211943281,"sku":"910-057","price":992.5,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1006\/8262\/9489\/files\/99774XL.jpg?v=1777437327","url":"https:\/\/wrench-lab.com\/products\/r-amp-d-flexible-shaft-coupling-f-5-b-w-hurth-amp-volvo-25hp-100rpm-capacity","provider":"WrenchLab","version":"1.0","type":"link"}