Thruster Cleaning & Polishing at Bissau Port
Full thrust restored when you need it most
Get a quote
Tell us the vessel, the port and the window. Scoped reply, usually the same working day.
Cleanship Marine cleans and polishes bow and stern thrusters at Bissau Port, Bissau. Divers clear the full tunnel bore, polish the blades and hub, and clear the gratings, restoring the manoeuvring thrust that quietly disappears while a vessel sits idle.
Thruster tunnels are the worst fouling trap on a hull — sheltered, still and almost never inspected. Growth builds on the tunnel walls, blades and gratings without anyone noticing until manoeuvring performance drops, and at Bissau — cashew exports on the Geba estuary, with one of West Africa's biggest tides — that tends to show at exactly the moment the thrust is needed.
Berthing at Bissau's pier across a strong tidal stream asks a lot of a bow thruster, and a tunnel fouled during a long stay delivers less of the thrust that manoeuvre needs. We clean thrusters at slack water during the call, with the unit isolated, so the ship has full control when she unberths.
What it gets you
- Manoeuvring thrust restored ahead of a berthing or a pilotage that needs it
- Tunnel and grating flow cleared, not just the visible blade faces
- Seal, boss and anode condition documented while the divers are already down
- Reduced reliance on tug assistance where thrust had quietly degraded
Working conditions at Bissau
Bissau lies on the Geba River estuary, where the tidal range reaches up to about 7 metres at spring tides — several times what most of the West African coast sees. The tide sets everything: the stream runs hard through the estuary, dives are only possible around slack water, and the water carries enough silt that divers work by touch. The pier offers around 7 metres of water, so ships often wait at anchor for the tide and the berth.
- Where we work
- Main T-shaped pier · Southwest pier · Bissau anchorage
- Vessels we see here
- Feeder container ships · General cargo ships · Product tankers · Fishing vessels
What we do at Bissau
- Full tunnel bore cleaned end to end, both openings, including the areas behind the gratings
- Blade and hub polished, with seal and boss condition inspected and reported
- Tunnel gratings cleared of growth and debris so flow is restored, not just the visible face
- Anodes inside the tunnel checked and wastage recorded
- Diving permission cleared with Administração dos Portos da Guiné-Bissau (APGB), with the thruster confirmed isolated and tagged out before the dive
- Video record of tunnel and blade condition before and after
Planning the window at Bissau
The combination of Atlantic swell and rain governs the calendar at Bissau Port, with the heaviest rain from May to October and swell running year-round. The swell here is long-period Atlantic ground swell rather than wind-driven sea, so it reaches the anchorages on days that look calm from the bridge and it is the single biggest cause of a lost in-water window on this coast. With a tidal range of up to 7 metres and strong streams in the estuary, every dive is timed to slack water and supervised from the surface, and the team works by touch in the silty water. A hull clean is split across several slack-water windows during the call.
Work is taken at the main T-shaped pier, southwest pier and Bissau anchorage, and which of those a vessel ends up at changes the dive plan more than the season does. Teams mobilise via Bissau (OXB), so give us the ETA as early as you have it — the travel is the flexible part, the approvals and the working window are not.
What we typically find at Bissau
Container tonnage on a fixed rotation shows the familiar pattern: light slime over most of the vertical sides, with the real accumulation in the flat bottom, the bilge keels and the niches where flow is slowest. Those are the areas that cost fuel and the ones a quick clean tends to skip.
Port stays at Bissau are long, often more than two weeks, and ships lie in warm, silty estuary water for much of that time. Hulls pick up heavy growth on the flat bottom and sea chests fill with silt and weed.
Standard scope of work
Included as standard on every thruster cleaning attendance, wherever the vessel is. Anything outside it is quoted separately and flagged before mobilisation, never added afterwards.
- Tunnel cleaning
- Fouling removed from the full length of the tunnel bore, including the areas behind gratings where growth is heaviest.
- Blade cleaning and polishing
- Propeller blades and hub cleaned and polished to restore surface finish and reduce cavitation-inducing roughness.
- Grating and guard clearance
- Gratings and rope guards cleared of growth, netting and debris that restrict flow or risk fouling the unit.
- Condition inspection
- Blade edges, seals and visible gearcase condition inspected and recorded, with any damage reported immediately.
How we deliver it at Bissau
- 1
Scope and vessel details
Tell us the vessel, her particulars, the coating specification and the window at Bissau. We come back with a defined scope, a crew size and a duration we will stand behind. Where the conditions here will not support what has been asked for, we say so at this stage rather than after mobilisation.
- 2
Permits and approvals
Administração dos Portos da Guiné-Bissau (APGB) approves the work alongside the local harbour master, and at a state port that conversation is quicker but less formal — it is worth having in writing. Diving permission, terminal approval and any environmental clearance for in-water work are handled by us, not left with the agent to chase.
- 3
Mobilisation to Bissau
Divers, compressors, brush carts and cameras mobilise via Bissau (OXB). Where a vessel is also calling at Banjul, one mobilisation is normally sized to cover both.
- 4
Safety setup and the dive
The vessel is secured for diving — main engine, shaft and thrusters immobilised, sea suctions confirmed shut, permit agreed with the master. Teams work under surface supervision with continuous diver communications and video throughout.
- 5
Report and handover
A completion report covering thruster cleaning is issued with before-and-after imagery, coating and anode condition and anything found that you should know about. The findings are discussed with the vessel rather than emailed and forgotten.
Bissau Port at a glance
- UN/LOCODE
- GWOXB
- Port type
- State Port
- State
- Bissau
- Country
- Guinea-Bissau
- Water body
- Geba River estuary
- Port authority
- Administração dos Portos da Guiné-Bissau (APGB)
- Main cargoes
- Containers (cashew exports), Rice and general imports, Fuel, Fishing catch
- Crew mobilisation
- Bissau (OXB)
- Services here
- Hull Cleaning
Frequently asked — Thruster Cleaning at Bissau
Do you provide thruster cleaning at Bissau Port?
Yes. Cleanship Marine works Bissau Port (GWOXB) in Bissau, Guinea-Bissau, covering the main T-shaped pier, southwest pier and Bissau anchorage. Teams mobilise via Bissau (OXB) with the full spread.
Why clean the thruster before leaving Bissau?
Ships unberth across a strong tidal stream, and a thruster fouled during a long stay loses power exactly when it is needed. We clean it at slack water before departure.
Can thruster cleaning be done while the vessel works cargo at Bissau?
Around slack water, alongside or at the anchorage — the long average port stay at Bissau usually leaves plenty of slack-water windows to plan a full clean. The vessel stays on hire throughout, and there is no diversion and no dry dock. We scope against the conditions at Bissau and tell you honestly whether the window you have is enough.
Do you need a diving permit from Administração dos Portos da Guiné-Bissau (APGB)?
Yes, and we obtain it. Diving permission from Administração dos Portos da Guiné-Bissau (APGB), terminal approval where the berth requires it, and any environmental clearance for in-water work are arranged as part of the job rather than left with the agent. The master's permit to work and the immobilisation of machinery are agreed on board before anyone enters the water.
What is underwater visibility like at Bissau?
Visibility at Bissau Port is low — the Geba estuary is tidal and silty, with strong streams except around slack water, and the combination of Atlantic swell and rain sets the outer limits of the calendar. How the tide and sea state shape the dive plan is set out in full in the working-conditions section on this page.
Which vessels do you carry out thruster cleaning on at Bissau?
Feeder container ships, General cargo ships, Product tankers and Fishing vessels — the traffic at Bissau Port runs to containers (cashew exports), rice and general imports, fuel, so those are the profiles we see most. The scope is sized to the vessel, not to a standard package.
How quickly can a team mobilise to Bissau?
Divers and equipment mobilise via Bissau (OXB). Give us the ETA and the window and we will confirm what is achievable rather than promise a date we cannot hold. Where the vessel also calls at Banjul or Conakry, one mobilisation is often sized to cover both.
What does thruster cleaning at Bissau cost?
It depends on the vessel's dimensions and wetted area, the fouling state found, the coating specification and the working window available at Bissau. We would rather scope it properly and give you a specific figure than quote a headline rate that changes once the work starts. Send the details and the window at Bissau and you get a scoped price, usually the same working day.
Thruster Cleaning & Polishing at Bissau Port.
Tell us the vessel, her ETA at Bissau and the window. You get a scope, a crew size and an honest duration — usually the same working day.