Hydraulic System

A good recommendation to follow is to install a new element in the oil filter housing before a hydraulic pressure test is to be made.

There is no adjustment for either the ahead or astern clutch. If a clutch does not engage or keep engaged when the control is in either the AHEAD (forward) or ASTERN (reverse) position, the hydraulic pump is damaged or the clutch discs are badly worn.

Operation Test

With the engine stopped, remove the plug from the tee in the control valve and install a 5M5317 Reducing Bushing in the tee. Install a 5S4648 Hose Assembly with an 8M2886 Pressure Gauge (0 to 600 psi) in the reducing bushing and tee.

OIL PRESSURE TEST

Start the engine and run it long enough to get the temperature of the oil, in the marine transmission, to approximately 150° F (65° C). Oil pressures are to be as shown in chart.

Remove the cover from the bottom of the control valve. Relief valve (3) and springs (1) can fall when the cover is removed. Add spacers (2), in relief valve (3) under springs (1) to increase the pressure of the oil to engage a clutch. Remove spacers (2) if the pressure reading on the gauge was too high.

Put springs (1), relief valve (3) with spacers (2) into the control valve and install the cover.

CROSS SECTION OF CONTROL VALVE
1. Springs. 2. Spacers. 3. Relief valve.

Test the oil pressure again. When the pressure reading is correct stop the engine and remove the hose assembly and reducing bushing. Install the plug in the tee on the control valve.

Vessel Either Pulled Or Pushed

Keep the propeller stopped when the vessel is either pulled or pushed with a stopped engine. The motion of the vessel can turn the propeller and there is no lubrication for the bearings and gears and clutch discs that turn with the propeller.

Marine Transmission Alignment

See the CATERPILLAR MARINE ENGINE APPLICATION AND INSTALLATION GUIDE for the correct alignment procedure. Also see Special Instruction Form No. SEHS7654 for alignment general instructions.