BASICS OF THE V351 Bennet trim Tab

WIRING. Harness colors and functions:

Red             Port Valve
Green           Starboard Valve
Blue            Pump Pressure
Yellow          Pump Retract
Black           - Ground
orange  + power ( 20 amp fuse )
Control is marked on bottom for color coding.

Markings on top of control refer to hull action. When the toggle is moved to port down, for example, the starboard trim plane lowers which in turn lowers the port side of the bow. Thus, when under way, the operator merely moves the control toggle in the direction of the high quarter of the boat and that quarter lowers.

  Mount pump as high and a close to transom a possible. Water can enter the trim pump reservoir, if submerged. Be sure to leave clearance for tubing, as it doesn't make tight bends very well. Use metal tubing supports, supplied with kit, if tight bends are required.

Facing pump, the left side goes to port (left) actuator, right to starboard. Note that solenoid valve wire on left is red and right valve wire is green matching the navigation light colors -- easy to remember.

Fill with DEXRON transmission fluid. Just run up and down a few times to bleed. Check for leaks. ( recheck level after a few uses out on the water)

(Refer to color coding above and it will clarify the following.)     Remove wires from control. Touching the positive lead to the colors as shown at left should provide results as shown at right.

Positive with blue & red                    Port plane down
Positive with blue & green                 Starboard plane down
Positive with blue, red & green          Both down simultaneously
Positive with yellow & red                 Port plane up
Positive with yellow & green              Starboard plane up
Positive with yellow, red & green       Both up simultaneously

If the opposite plane moves to that described above, the tubing is reversed at the pump.

The control toggle operates through an arc of about 45o in the "both-up" and "both-down" positions (about 20o-25o either side of straight forward or straight aft). To get one plane only, the toggle should be moved to the 45o marks on the control.

If trim planes go down but will not come up, it is normally caused by low voltage. To ascertain low voltage, check voltage while pump is running with a voltmeter at the pump end of the wires. If the voltage is less than 9V, the valves will not open.

Although infrequent, water can enter the trim tab system. The two possible sources for water entry are:
* The pump is submerged in bilge water.
* The seals in the trim rams have started to leak.
 It is a good idea to periodically check the fluid for water entry. The normally translucent reddish color of Dexron fluid will change to a strawberry milk shake color.

Tip: Retracting the trim tabs, when not in use, can help protect the trim rams from damage and marine growth. 
Although the trim tabs themselves do not typically require anodic zinc protection; zinc disks should be installed, on the stainless steel tab, to help reduce corrosion of surrounding, more sensitive, materials.

Parts blow-up of Bennet pump and reservoir.

Telephone help may be obtained by calling Bennet Customer Service at:  

Phone: 954-427-1400      Fax: 954-480-2897

Bennett Marine's Client Services Department May Be Reached From 8:00 AM - 5:00 PM Eastern Time,  Monday - Friday


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