This Bennett hydraulic power unit for trim tabs is model V351HPU1 in the V351 HPU series. The 12 V DC electro-hydraulic unit is used as a replacement unit in compatible hydraulic trim tab systems and creates the hydraulic pressure that lowers, raises, and holds the trim tabs.
The unit consists of a hydraulic pump, two solenoid valves, a hydraulic fluid reservoir, and a Lexan/polycarbonate protective cover. The solenoid valves direct the hydraulic fluid to the relevant actuators and close tightly, allowing the trim tabs to be held in the selected position. The transparent reservoir makes it possible to visually check the fluid level.
The V351HPU1 is designed for 12 V DC and has an approximate current draw of 18 A after break-in, with a documented maximum current draw of 20 A. In a 12 V system, a recommended 20 A in-line fuse is used in the power line for the controls. The wires have separate functions for port and starboard solenoid valve, pump direction, and ground.
The unit itself measures 4 × 7.5 × 5.5 inches, corresponding to approximately 10.16 × 19.05 × 13.97 cm. The hydraulic system uses automatic transmission fluid (ATF). For an installation with one actuator per trim tab, the approximate total fill volume is 22 US fl oz, approximately 651 ml. With the trim tabs fully retracted, the reservoir is filled to the marked full line or to the prescribed level.
The hydraulic connections are designed for tubing with a 1/4-inch outside diameter and use fittings from 1/8-inch pipe to 1/4-inch tube. Viewed from the front, the left brass connection connects to the port actuator and the right to the starboard actuator. In a system with one actuator per side, the approximate travel time is 8–10 seconds for both trim tabs and 4–5 seconds for one trim tab. Systems with two actuators per side take approximately twice as long.
The unit must be mounted in a dry area where it cannot be submerged or exposed to heavy water spray. The cover protects against occasional water exposure and wash-downs, but the unit has no documented IP rating. There must be approximately 76 mm of clearance above the unit for mounting. Mounting bracket H1179 is sold separately; the distance between the bracket's top mounting holes is approximately 117.5 mm.
Compatibility and spare parts
The V351HPU1 is used in Bennett Standard/Classic hydraulic trim tab systems as well as M80 and M120 Sport systems. The manufacturer number is V351HPU1, and the unit has Yamaha part number 6BT-50086-73-00. Red 12 V solenoid valve VP1135R for the port side is available as item no. 51.232.01, while green 12 V solenoid valve VP1135G for the starboard side is available as item no. 51.232.02. Mounting bracket H1179, screw H1180, and pigtail PT110 are separate accessories and are not included.
Key featuresElectro-hydraulic replacement unit for hydraulic trim tabs
Model V351HPU1 in the V351 HPU series
12 V DC with approx. 18 A current draw
Maximum current draw: 20 A
Hydraulic pump with two solenoid valves and fluid reservoir
Lexan/polycarbonate protective cover
For hydraulic tubing with 1/4-inch outside diameter
Uses automatic transmission fluid (ATF)
Product dimensions: 4 × 7.5 × 5.5 inches
Mounting bracket H1179 sold separately
