If you have problems to open the hooks, the first step must be disconnect the cam hook of the clevis wire. once did it you can check moving the release handle. I describe a real situation..

Basic Principles on the falls prevention devices as MSC.1/Circ.1327

Hatecke cruise tender and lifeboat, type PL11. Testing navigation on the river Elbe

Oriental's instructions: How to inspect Lifeboat Davit Floating Block

Lifeboat and rescue boat system developed for NORSOK R-002. This lifesaving appliance has a very high safety level to prevent accidents during testing, training, and emergency situations offshore. The system is redundant and capable of running in multiple failure modes.

If you are a manufacturer,lifeboat or davit, you can send me your company description for publish it in my blog.

Fiberglass reparation on the hull of the lifeboat. The lifeboat Shigi had a hole on the hull, aft pòsition due to schock with the davit. The hole diameter was ten centimeters

Maintenance carried out to hooks of lifeboats. Material used: grinder with wire brush, sand paper, chisel, protective coating of zinc cold. (spray), red paint. (spray)

Fiberglass reparation on the rescue boat keel. A rescue boat was damaged in the keel. This keel had three damages, two of them very important.

MALFUNCTION OF PROXIMITY SWITCH (MAIB SAFETY BULLETIN 2/2011).Republic of the Marshall Islands Office of the MARITIME ADMINISTRATOR