The PRM150 marine gearbox is purpose built for use with both pleasure craft and commercial boats; its twin countershaft design provides separate oil-operated multi-disc clutches (which need no adjustment) for ahead or astern drive allowing full rated power to be transmitted continuously in either direction.
The reduction ratios offered (1.53:1. 2.09:1 and 2.82:1) are all available for left-hand or right-hand propeller rotation in "ahead", making PRM150 particularly well suited to twin engine installations.
The heavy duty aluminium alloy gearcase is internally ribbed for rigidity and strength and consists of two separate halves to facilitate servicing.
The hydraulic operating system functions on normal multigrade engine oil, avoiding the need to use automatic transmission fluid, and ensures rapid response to movements of the operating lever for good boat handling. The operating lever has a positive neutral detent and is suitable for use with proprietary single lever remote control operating systems.
Robust and reliable, the hydraulic system is nevertheless provided with a mechanical lock up device for added security, so that in the unlikely event of a hydraulic failure the boat can be brought safely back to port. Access to this device is via the detachable manifold on the rear of the gearcase which also houses the hydraulic control valve.
|Pleasure||2.1 BHP (1.6kW) per 100 rev/min operating speed|
|Commercial||1.5 BHP (1.1kW) per 100 rev/min operating speed|
|Max. Input Speed||5000 rev/min intermittent, 4500 rev/min continuous|
Note: These powers have been measured at the engine flywheel. Ratings have been established to ensure the long trouble free life of the gearbox which should not, therefore be used at powers in excess of those shown.
Limited to craft used exclusively for pleasure boating; operation at full engine throttle should not exceed 5% of total time, with balance of usage at 90% of full throttle engine speed, or less. Maximum operation 500 hours per year. The selection of PRM150 according to this classification for any commercial boat is not approved by Newage Transmissions Ltd.
Newage Transmissions Ltd recommends that when considering the PRM150 in boats of whatever hull form used in commercial applications, and semi-displacement hull boats for pleasure applications, these boats should be classed as commercial duty and the gearbox selected accordingly.
Newage Transmissions Ltd will provide all possible information and assistance to help find solutions to potential torsional problems, but it is the ultimate responsibility of the person assembling the drive and driven equipment to ensure that they are torsionally compatible.
Minimum - 2500 kPa (370 lb./in²), Maximum - 2850 kPa (420 LB/in²). A tapped hole 1/8" BSP is provided in the rear manifold so that a pressure gauge can be fitted if required.
The normal operating temperature of the oil should be in the 50°C - 80°C range and should not be permitted to exceed 90°C. An oil cooler is necessary to ensure that correct operating temperatures are maintained, and the gearbox is provided with two ¼" BSP connectors to allow it to be fitted. The size of the cooler depends on a number of factors including the transmission horsepower, operating speed, duty cycle, inlet water temperature and ambient temperature.
The PRM150 output shaft can be rotated continuously with the gearbox in neutral. It is therefore not necessary to fit a propshaft brake when running with the engine shut down, e.g. in multi-engine installations or when sailing.
|Approximate dry weight||21kg (46lb) excluding drive coupling, adaptor flange and oil cooler|
|Oil capacity||1.4 litres (2.5 pints) plus the amount necessary to fill the oil cooling circuit.|
|Part Number||Outside Diameter||Mounting Hole Pattern||Remarks|
|in||mm||No.||Diameter||Pitch Circle Dia.|
|MT4904||8.50||215.9||6||0.344||8.74||7.875||200.0||SAE 6 1/2 in|
|MT4905||9.50||241.3||8||0.344||8.74||8.750||222.25||SAE 7 1/2 in|
|MT4908||5.965||151.5||8||0.256||6.5||5.512||140.0||Hawker Siddeley Marine|
|MT4902S/A||Special SAE4 adaptor, Volvo Penta 2000 series||10.0||22.0|
|MT4903S/A||Special SAE5 adaptor, Volvo Penta 2000 series||2.7||6.0|
|MT8083S/A||B/W ( Velvet Drive) adaptor||1.4||3.1|
|MT0149||Oil cooler, complete with pipes and bracket||1.5||3.3|
|MT3054||Tailshaft half coupling ( pilot bored)||1.3||2.9|
|MT3056||Tailshaft flexible coupling||0.7||1.5|
|MT4733||Oil pressure gauge, direct mounting||0.1||0.2|
|MT0156||Neutral safety start switch||0.04||0.1|
installation drawing for the PRM150 in PDF format (78kb)
parts list for the PRM150 in PDF format (642kb)
The PDF files on this website can be read online or printed using the
free Adobe® Acrobat® Reader.
If you do not have this software installed on your system, you may download it from Adobe's website.
|All information given in this website is correct at the time of publication. However in the interests of technical progress, design specifications are subject to change without notice. Accordingly, data given herein should be regarded as a general guide only and does not form part of any contract. All goods are supplied in accordance with our standard terms and conditions of sale.|
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