PRM NEWAGE PRM 125, Workshop Manual

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PRM 125
Input Shaft:
28.5mm diameter with 10 tooth spline to DIN5464.
Propeller thrust:
Ahead and astern thrust is carried by output shaft bearings of ample capacity for the approved rating.
Output Flange:
102mm diameter, with 4 holes 10.5mm diameter on 82.5 pitch circle diameter.
Installation angle:
The maximum fore and aft installation angle at rest is 15°.
2. INTRODUCTION
Prior to installation the PRM 125 read and follow the instructions within this manual. Failure to do so will make the
warranty void. PRM will not be responsible for poor installation,
wrong handling or defficient maintainence. It is it is the
responsibility of users to install guards and safety devices within maybe required by Health and Safety directives within
different countries.
The PRM 125 marine transmission is a simple, lightweight, mechanically operated gearbox for use in pleasure craft.
Ahead and astern is selected by engaging a cone clutch which requires no adjustment. The PRM 125 can only be
installed onto engines that
rotate left hand (anti-clockwise) as viewed when standing behind the gearbox output
coupling facing towards the engine flywheel.
3. CONSTRUCTION
3.1 Gearcase
The gearcase is made from heavy duty aluminium alloy rigidly designed and externally ribbed for efficient heat
dissipation. The case assembly comprises two halves vertically split to facilitate servicing.
3.2 Gear train
The helical Gear train is manufactured from high grade steel with all gears being case hardened for long life. All shafts
are supported on taper roller bearings which are amply proportioned to absorb all the thrust from the propeller.
4. OPERATION
4.1 Output Rotations
With the control lever in the mid, or neutral position no power is transmitted to the propeller as the cone clutch is not
engaged with either ahead or astern gears. Moving the lever forward i.e. towards the engine selects ahead, and
rearwards i.e. towards the propeller selects astern. In ahead the output shaft rotates in the opposite direction to the
input shaft (which rotates as engine). It is therefore necessary to fit a right hand propeller.
4.2 Lubrication
All lubrication is supplied by internal splash with oil cooling being by radiation through the gearbox case.
4.3 Approved oils and oil filling
The gearbox is supplied direct to the distributor/ coustomer without oil and therefore prior to start up it must be filled with
oil. Unscrew the Oil Level Plug located on the side of the gearbox. Unscrew the oil filling plug located on the top of the
gearbox. Fill the gearbox with ATF DEXTRON II, III, or IV to GM specification or engineering approved equvalent until
oil starts draining from the level hole. Refit the oil level plug. Check the oil on the dipstick. Refit the oil filller plug. The oil
is approximately 0.4 litres.
CAUTION:
Do not mix different brands, types or grade of oil.
DO NOT OVERFILL THE GEARBOX AS THIS AFFECTS THE GEARBOX PERFORMENCE.