Harken MKIV Jib Reefing & Furling Unit 0 — Installation Manual

Adhesive

• Joints are bonded with 3M 5200 on dry connectors and foils, using the supplied injector.
• Cure is best at 70°F (22°C) and 50% humidity; do not apply below 40°F (5°C) or above 100°F (38°C).
• Fill the injector less than half way and use the adhesive within 3 hours.
• Inject only 1/4 to 1/3 ml per joint; stop as soon as adhesive shows in a screw hole.
• Foils can go up and sails be fitted right away; if possible leave a couple of days before sailing. 4200 Fast Cure is the faster option.

Joint Assembly

• Bushings on the stay with the hooked part of the longer half facing out.
• Slip the 6.5" (165 mm) connector on, red Loctite in the screw holes, hold the plastic wedge in with your thumb as it enters the foil.
• Use the 10" (254 mm) bottom connector for the bottom foil.
• Halyard swivel goes on above the feeder window, taller half up.
• Remove adhesive from sails with acetone. Damaged foils can be separated by heating the joint with a hand-held propane torch.

Halyard and Swivel

• Halyard swivel within the top 4–6" (100–152 mm) of the foil unless a restrainer is used.
• Halyard must pull slightly aft, 8–10° from the foil. This angle is what prevents halyard wraps.
• If the sail is too short, add a permanent plastic-coated wire pendant at the head. No adjustable pendants.
• Halyard firm but not tight; ease it when the boat is not in use. Charter boats should have a restrainer.
• Tie the prefeeder so it sits 2' (610 mm) below the feeder.

Turnbuckle and Furling Line

• To adjust the turnbuckle, loosen the drum clamp screws, lower the foils, lift the drum about 5' (1.5 m) on a halyard and hold the foils on a second halyard.
• Adjust foil height by loosening the clamp screws and pulling the clamp away; do not remove the screws.
• Feeder screw is plastic-coated against vibration: loosen no more than one full turn to remove it.
• 7401 forward block at 90° to the headstay; 7402 ratchet as the furthest-aft lead, line turning at least 90°; #10 (5 mm) fasteners.
• A Unit 0 should never need a winch to furl.

Clean and Store

• Flush with soap and fresh water whenever you wash the boat; occasionally flush the halyard swivel.
• At least twice a year remove the line (note spool direction) and flush the bearings.
• If lubrication is needed, spray a thin coat of McLube SailKote on the luff tapes away from the deck.
• Replacement line: HFG594, or 9/32" (7 mm) with break strength over 2500 lb (1130 kg); smaller boats may use 5/16" (8 mm).

Inspect

• Clevis and cotter pins below and inside the drum assembly; headstay tension.
• Swage fitting and lower toggle for stress corrosion.
• Norseman, Sta-Lok or rod terminals, and all screws on the unit.
• That the foil has not dropped into the drum; the wire for wear or unravelling.

A furled sail must have:

• Two to three wraps of sheet around the furled sail.
• At least two wraps of line left on the spool. With none, the line deadend can break the drum when motoring through waves.
• Furling line securely cleated; sheets on the winch and in the self-tailing jaws.
• Remove the sail if extreme winds are forecast, especially with the boat unattended.