Is your Cristal Hatch or Portlight staying out?  You might need to change the friction hinge, or simply tighten them up.

Replacement Hinge kit for Cristal Range Hinge 

• Can be simply tighten to hold lid in place

• Sold in pairs (one pair per hinge) 

Suits the following Hatches – 

• 24.19 (Size 01)

• 24.24 (Size 10) 

• 35.21 (Size 20) 

• 36.14

• 36.19

• 36.24 (Size 36)

• 49.19 

• 49.24

• 23.23 – Evolution 

• 32.18 – Evolution 

Suits the following Portlights – 

• 23.10R

• 33.13

• 33.13R

• 43.18

• 43.18R