Known Usage:
• Catalina 310
• Catalina 34
• Catalina 350
• Catalina 36
• Catalina 42
• Catalina 470

Additional Usage: Late production of these boats may have been changed from Bomar to Lewmar in the early 2000's. Exact date is unknown:
• Catalina 270
• Catalina 28
• Catalina 320

There may be other instances where this hatch is used. It is also possible that not every boat described above used this hatch. Please use the dimensions above and the photos below to verify which hatch is actually installed on your boat.

• Outside of deck flange
aft edge: 653mm (~ 25.7")
forward edge 540mm (~21.3")
fore to aft 536mm (~21.1")

• Outside of lid:
aft edge: 680mm (~ 26.8")
forward edge: 557mm (~21.9")
fore to aft, including handle: 567mm (~22.3")

• Height off of deck: 37mm (~ 1-1/2")

Please note that these hatches are built in England and made to metric system standard dimensions. All Imperial equivalents are approximate.

1) This gasket will only fit a Lewmar Ocean model hatch. It will not fit a Lewmar Medium Profile or Low Profile hatch. It will also not fit a Bomar hatch. The Lewmar Ocean hatch was the most commonly used hatch on these boats. However, if Lewmar ran out of Ocean hatches, Catalina may have been forced to use a different hatch in your boat. As a result, any of the hatches mentioned may have been installed on your particular hull.

2) The original style gasket is held in place by the same sealant that secures the lens in the frame. Although possible, replacing the gasket is tricky. Removing the lid from the deck flange will make the process somewhat easier. We recommend having the hatch professionally refurbished.

3) In August of 2023 Lewmar changed the gasket design for their Ocean hatches which uses a 3M adhesive tape that is fused to the EPDM rubber seal. This makes the gasket easier to replace. Both the earlier and later style gaskets are still flowing through Lewmar's complicated supply chains, so either version may be sent to fill your order. See images and instructions for more details. Lewmar size 65