Indel Webasto Marine Compact Classic Instructions Pour L'installation Et L'utilisation page 74

"O" joint connection:
1. Remove covers.
2. Check that the gasket seal on the male joint is lubricated with system fluid.
3. Move the female joint and tighten the rotating nut on the male joint.
4. Insert half the joints by hand to ensure correspondence with threading, using
appropriately sized spanners (in the hexagonal body of the joint and the unit
nut) until the two sides are connected to the bottom or until you feel definite
resistance.
5. Use a marker or a pen to mark the line in the direction of the length from the joint
nut to the division, adding another 1/6 or 1/4 of a turn. Line misalignment will
act to indicate the degree of tightening. The final turn has the purpose of ensuring
that the metal edge enters into the brass housing of the two joint components,
forming a leak-proof connection. Tightening torque values must be complied with.
74
Figure 10: "O" quick coupling type
User Manual