IPS PODS AND SHALLOW BERTHING IN MUDDY SEABED

[aitch008]

Hi Everyone, I'm looking at buying a Riviera 4800 Sport Yacht with IPS pods. Our mooring pen is 4 feet 7 inches (1.4m) deep at lowest tide with a soft silty mud bottom.

The boat specs:

• Draft: 4 feet 1 inch (1.25m)
• This leaves only 6 inches (150mm) clearance between the pods/props and the muddy seabed at very low tide

My concerns:

• Mud contact damage:Has anyone berthed IPS boats in similar shallow, soft mud conditions? Would the pods/props touching soft silt during:
  • Low tide (boat settling slightly into mud)
  • Wake/wave action (temporary contact)
  • Maneuvering in the pen...cause damage to the IPS drives, seals, or props?
• Natural prop wash dredging: When entering/leaving the pen regularly, does the prop wash gradually deepen the area over time? If so, what's been your experience - how much deepening per year?

• Any experiences or advice, would be greatly appreciated!

 

[PascalG]

Soft silty bottom isn’t going to cause any damage to the pods. Your biggest concern is going the amount of silt you will stir up coming in and out. All that stuff is going to end up going thru the strainers and cooling system, not just engines but gen and air con as well.

Depending on the grittiness of the silt it could shorten the life of impellers.