Around southern Africa boat owners are, or should be, running through basic maintenance of their vessels, in preparation for the coming summer months. While it’s crucial to make sure that the electronics and engine are always in optimal condition, it’s equally important to take care of the hull, at intervals of around 12 weeks (at most). Of all the parts of a boat, it’s the hull that takes the biggest battering from sea water and sunshine.

It’s not just about having a good-looking hull, either – The gel coat on a jet boat’s fiberglass hull has to be kept clean because if it’s left to become dirty and greasy, it will eventually oxidise, becoming chalky, waxy and ugly. Eventually, its integrity will weaken.

Here are the steps to take for regular hull maintenance:

Your boat should be out of the water and secured to its trailer for cleaning purposes.

The first step to cleaning your boat’s hull is simply rinsing it down with fresh water. Don’t use a high-pressure hose for this; you just want to rinse any algae, dirt, salt, sediment or other unwanted matter off the fiberglass surface (it’s actually wise to rinse off your hull after every trip).

If rinsing isn’t enough, you can use a quality boat cleaner designed specifically for boat hulls. An eco-friendly boat cleaner will be gentler on both your boat and the environment.

Use a soft, large sponge to wash the hull with the cleaner in gentle, circular strokes, scrubbing from bow to stern.

Rinse with fresh water when you’re done, then go over the boat’s hull once more with a clean sponge soaked in water. This will remove any lingering residue.

Let the hull dry and then apply a suitable wax coating. This helps to prevent the sun from dulling, pitting or oxidising the gel coating. You want to apply the wax with a soft cloth then rub it in with gentle, circular movements. If you have a big boat, you may prefer to use a buffing tool – run it at the lowest setting. Across the hull, you want to buff until the surface becomes glassy looking.

These are the basics of regular hull maintenance, which should be all you need to do every two to three months if your boat is still fairly new. However, older boats may develop more complex hull issues:

  • If your boat has a lot of hard-set grime or barnacles, you may need to use a high-pressure hose on the hull, 15 minutes after applying muriatic acid (no longer) – however, this is a dangerous caustic substance and we would advise you to call on professional help.
  • Cracks can develop in the hull’s fibreglass and gel coating over time, as a result of flexing, UV rays or other causes. These need to be taken care of early or they can spread and weaken the hull’s surface integrity. For most cracks an epoxy resin filler or fibreglass/gelcoat filler can be used, left to dry and then painted over to match the hull’s colour. For repairing deep cracks, you’d do well to contact a professional.
  • Cracks and crazing aside, the integrity of the hull’s gel coating should last up to 15 years without intervention, after which you would need to start replenishing the hull’s gel coating every two years or so.

Southern Power’s Service Manager, Dan Nelson, comments: “A dirty hull is extremely detrimental to the performance of your vessel. It causes poor performance, high fuel consumption and unwanted stress on your drive line. It’s like asking your ten year old son to push a tree trunk up a river!

Your boat’s hull is like the tires on a supercar or superbike – the better the condition of the “tires” the better it performs. Sleek clean hulls glide easily over the water. Dirty hulls with marine growth will not get up and run as they should.“

While basic boat maintenance – including the hull – can be handled by most boat owners, It’s worth consulting a local reputable service dealer if you need qualified advice or servicing. Southern Power is partnered with a number of marine services dealers across South Africa – click here for more information. Their qualified marine technicians can give you qualified advice on proper hull maintenance.

Our mission at Southern Power is to provide exceptional experiences, comfort, and durability to boat owners. We support you whether you self-service your own vessel or seek expert guidance. Contact our team for assistance or advice: or call 021 511 0653 | 021 510 3049.