TPD 1317e Chapter 1 1.3 Flexible Engine Mounts It is recommended that flexible engine mounts should be used for all applications. The principal purpose of the mounts is to reduce the transmission of vibration from the engine to the hull, but another valuable advantage is that the mountings reduce the shock transmitted from the hull to the engine under adverse weather conditions and also prevent the engine being inadvertently used as a structural part of the boat, due to hull flexure, a function the engine will not satisfactorily fulfil. Figure 6 shows the leading dimensions of the flexible engine mount which is satisfactory for most applications.
Engines used with unusual drive arrangements, such as ‘V’ drives when integral with the engine unit, pose special mounting problems and recommendations as to the most suitable mounting arrangement can be made for specific applications. Where transmission ratios in excess of 2.5:1 are employed, or where extreme service conditions can be expected, (e.g. fast rescue boats) the standard mount should not be used, and a recommendation should be obtained for the specific application. Installation drawings are available showing the preferred mounting arrangements when using a variety of gearboxes.
Height adjuster bolt and nut Height adjuster pad *Minimum 125(4.9) *Maximum 137(5.4) (Bottom of mount to crankshaft centre line) A maximum of 13 shims can be used per mount, 11 at 1mm thick and 2 at 0.5mm thick.. Radially slotted hole Dimensions:mm(inches) *Dimensions given are for the mount in the unloaded condition Figure 6 - Typical flexible engine mount - refer to installation drawing for specific applications. Page