Max Power CT165 & CT225 Tunnel Thrusters — Installation Manual

Specifications (Data Sheets)

The CT165 data sheet text also quotes a thrust rating of up to 160/352 (kg/lbs). Thrusters are designed to run at 22V on 24V units; performance at one tunnel diameter immersion, tunnel no longer than twice its diameter, +/- 6%. Delivered without fuse, fuse holder or control panel.

Position, Tunnel, Drive Leg, Motor

• Minimum acceptable tunnel position: 188mm below the waterline. Ideal: 250mm between the waterline and the top of the installed tunnel. As far forward as possible.
• Support the motor whether vertical, inclined or horizontal; dry, ventilated compartment; batteries charged by alternator and charger, a dedicated bank as close as possible to the thruster.
• Drive leg centred in the tunnel; propellers must never protrude.

1. Tunnel: mark the centre on both sides, drill 8–10mm holes, trace the ellipses with a 132mm-radius compass, cut, grind approx. 10 to 15cm around, fit with reinforced fibreglass filler and laminate a minimum of 8 layers of ISOPHTALIC RESIN with mat and roving; finish and apply a watertight barrier. Do not laminate the motor-support area.
2. Drive leg: mark the holes with the motor support and gasket, check with the gasket, dry-fit and check alignment with the propellers. Coat both sides of the gasket with silicone grease or sealing compound and tighten the two 10mm screws alternately with a 6mm Allen key (maximum torque: 35 Nm). Keep holes and screws free of compound; no graphite grease. Use only the original screws.
3. Motor: push the lower coupling onto the lightly greased leg shaft, fit the flexible black coupler (part 8), set the motor on the support and tighten the four 10mm motor support screws alternately (maximum torque: 40Nm). Push the lower coupling up with a screwdriver and tighten the two 4 x 10mm Allen screws (maximum torque: 10Nm). Leave 2mm of play (+/- 1mm) between the couplings; the motor-side coupling is factory set.
4. Propellers: fit the drive pins and propellers, position the blades so they are not horizontally aligned and not directly opposite each other, and tighten the 22mm nut (maximum torque: 25Nm). Coat shaft and stainless cover with silicone grease.
5. Protection grills may be fitted but can affect performance.

Electrical Installation

• A manual battery isolator is essential (visible, clearly marked, accessible), plus if possible an electric battery isolator: Max Power advises ref. 318401 for CT165 and ref. 634424 for CT225. The control box supply must match the nominal voltage of the main relay and battery isolator.
• Reference: batteries at 25.4V; approx. 560A and 22V for the CT165, and 690A and 22V for the CT225, at the motor connections. Motor voltage while running approx. 22V for a 24V system.
• Power cables: shortest route, well ventilated, PVC insulation rated 105 degrees Celsius or more; M10 terminals.
• Batteries: maintenance-free starting type, e.g. Exide Maxxima 900, 12V, 55Ah / 800CCA. CT165 needs 1680CCA total output and 100 Ah for 10 min/day; CT225 2400 CCA and 120 Ah. With lithium batteries the thruster current must be regulated not to exceed their maximum; with alternator charging, take the charge after the diode-splitting block.
• Control box: fused breaker / switch marked BOW THRUSTER on the main DC panel, ideally fed from a different bank than the thruster; 8A fuse on the control box positive; voltage drop in the control cables under 5% of nominal. Without an electric battery isolator, seal off the two grey wires from the control box and isolate the motor circuit with the manual isolator after use.

Size the fuse on the cable sections in the circuit, NOT on the motor amperage.

Operation & Maintenance

• ON: one beep and the green LED in the red push-button lights; OFF: two beeps and the LED goes out. A time delay separates left and right thrust (none to the same side).
• Red button or joystick left = boat moves left; green button or joystick right = right. If reversed during tests, swap the blue and brown wires on the power relay.
• Thermal switch fitted as standard: on overheat the buzzer beeps (5 intermediate beeps) and the green LED flashes; 10 seconds of thruster use remain before shutdown, then no restart until the motor cools.
• Never run the thruster out of the water (safety, and it can damage the motor). Test in the water, batteries 100% charged and on charge, engines running.
• Measure voltage at batteries, cut-off switch, fuse, motor connections and control box supply to find voltage drop. Switch off after use at both the DC panel and the thruster battery isolator.
• Automatic switch-off after ten minutes without use. Maximum continuous runtime S2-2.5 minutes, affected by ambient temperature.

Maintenance

• Check battery condition and charge and all connections regularly; remove the motor and blow dust out of the brushes with compressed air; keep the motor dry and ventilated.
• Composite drive leg: oil-filled and sealed for life, no oil change, no anode, never disassemble (voids the warranty); worn oil seals = standard exchange leg.
• Keep propellers and tunnel clean, antifoul over primer, and grease the drive shafts and stainless seal covers with silicone grease annually. No aggressive solvents.

Spare Parts

The separate spare parts sheet (July 2013) also lists motor + relay 315346 (CT165) and 315347 (CT225), and some different new codes: pin 630490, propeller 35032, inox nut 630491, electronic controller 315308, pin no. 12 312015. Order by the current list above.