New Products: Harken Single-Acting Integral Backstay Adjuster

SinC Harken Backstay Adjuster

May 4, 2022

It’s one of the best things about sailors: we hate to give up on our equipment. But if you’re like a lot of owners of boats with vintage integral hydraulic backstay units, you’ve been putting up with seepage and slippage for too long. We’ve introduced our new integral hydraulic unit to convince you it’s finally time to pull the pins on that leaker and start anew.

Unlike some competitive units, you’ll notice the Harken Single-Acting Integral Backstay Adjuster has no external hydraulic hoses to snag dock lines or lazy sheets and come loose. As you pump the handle, the single-acting pump pushes fluid through a hole gun-drilled inside the stainless rod, to top of the cylinder, creating pressure and backstay tension. A simple pressure-release knob releases that pressure, reducing mast bend. All the fluid stays inside the tube all the time.

Harken’s integral hydraulic backstay adjuster provides the power to optimize sail shape quickly for racers and adjust mast tension for smoother furling for cruisers.

The cylinder features a built-in, single-acting pump. Every unit includes a hardcoat-anodized aluminum cylinder and pump, valve, and stainless pump handle with two attachment options: 1) a roll pin, that when installed, locks the handle permanently, 2) the roll pin can be left off and the handle may be inserted when needed, but stored separately.

SinC Harken Backstay Adjuster 2 400Cylinders include a clevis pin on both ends. A fiberglass position indicator attached to the top clevis pin slides down the cylinder as it’s retracted for repeatable tension settings. Standard eye-jaw toggles fit all Harken cylinders and are recommended on all installations.

The pressure-release knob turns clockwise to close and pump, counter clockwise to release. When closing the pump, the knob cannot be over-tightened by hand, preventing damage to the valve. Release speed depends on how far open the knob is turned. Pressure relief is factory set to prevent crew from over-tensioning the backstay.

The new Harken Integral is designed to be bulletproof and need no nursing for years. That pressure-release knob cannot be over-tightened. Turn it clockwise to close, counter clockwise to open. A very analog, very pragmatic position indicator completes the offering — to make duplicating settings fool-proof.

Harken integral backstay adjusters come in four sizes to fit boats 9 – 18 m (30 – 60′) with stay diameters of 5 – 10 mm (7/32 – 3/8″).

Watch this video for the inside scoop:

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