Gilbert Park shares his tips for allowing motorboats to dry out safely

Next to a wall adjacent to my house, I have been drying out motorboats each tide for about 12 years.

For me, it was both an economical and convenient way to use my boat.

Mud in some of the moorings can be both a blessing as boats can sit in it and a curse as it makes maintenance messy and causes the loss of Wellington boots as they get stuck in the mud.

A neighbour of mine decided he wanted a boat to dry out in his mooring that has deep mud.

A boat with a wooden hull drying out on mud

Some harbours place supports for flat bottomed boats to help them rest upright. Credit: Gilbert Park

To do this I had to do some serious research into large motorboats that dry.

This involved visiting lots of boats, contacting manufacturers and owners clubs, as well as visiting the Southampton Boat Show three times!

It’s also important to think about whether or not you are cruising on the boat or just using it as a day boat.

If you are going to live on the boat then you need a boat that will be level when dried out.

Types of hull for drying out

Not all boats can dry out and hull and stern gear types are important.

Boats with IPS drives and unprotected propellers can’t dry.

Some boats have protected propellers, but the protection may be designed only for preserving the prop in an inadvertent grounding or to stop ropes and netting from tangling around the prop.

However, some are designed to allow the boat to ground. The classic drying boat is the bilge keeler.

Stern gear on a boat

This stern gear protector is on a yacht with a winged lifting keel. It dries every tide. Credit: Gilbert Park

While common in sailing boats it’s rare in motorboats and only a few are made, for example, the Trusty T21 and 23.

These have a central deep keel and twin, lead-weighted keels on either side. When dried out they are level.

Other boats have stubby bilge keels that are not as deep as the main keel, so when these dry out they lean to one side or another.

Many outboard-powered planing boats can dry out with the engines up.

If they are to be dried out each tide, then some protection of the hull may be needed if there’s a hard seabed.

This can be a bed of old tyres. While effective, it is not environmentally friendly, and they should be fixed together and anchored so they don’t get washed away.

\When the boat is moved on the tyres should be properly recycled, not just left on the seabed.

An alternative is to fix something like KeelGuard to stop the keel from being worn through by stones and grit.

A prop protector on the hull of a boat

This prop protector is for accidental grounding and to deflect debris from the prop. It’s not intended for regular drying out. Credit: Gilbert Park

There is some debate about the drying of boats with drive legs. Some of them come with a beaching position, but in deep mud the water inlet/outlets may be blocked by mud.

Some mechanics have expressed concerns about the rubber gaiters being damaged.

Manufacturers may fit a protective scoop to the hull to overcome some of these difficulties.

One of the most popular types of boat for drying has a single engine that has the rudder and the propeller protected by a long central keel, perhaps with an additional sacrificial keel shoe – typified by the Nelson type of hull.

To stay upright the boat must be leant against a wall or piles or need legs.

Boats with a long central keel that have twin engines usually have to stay upright when dried out so that no weight is put onto the propeller, shaft, P-bracket or rudders.

Catamarans can also take the ground easily. Keel protection and/or reinforcement may need to be fitted to the hulls.

The blue hull of a motorboat

The Landau’s cathedral hull shape allows it to dry out on a level bottom. Credit: Gilbert Park

Then there are ‘cathedral’ hulls like the Landau 20. They have a flat central section and two smaller sponsons.

Like catamarans, they dry out well and remain upright.

Many owners, despite what the manufacturers have designed, will allow their boats to dry in deep mud and take the risk.

To lean or not to lean…

If the boat is going to dry then the question is whether it lies on its side or is kept upright.

On a hard seabed, a boat with twin props has to dry out with them not taking any weight.

Continues below…

Single propped boats or those with outboards or inboard/outboard legs that are raised may dry out on their side.

There are various ways of keeping a boat upright – lean it against a wall or poles or use legs.

Walls or poles for drying out

If you have a wall to lean the boat against then this may be the easiest way to keep a boat upright.

You can decide which way you want a boat to lean by placing a heavy weight on that side.

However, be careful if the boat has guard rails because they may be wider than the maximum width of the hull and get bent by the resting weight.

The wall itself may cause problems if it’s rough concrete or the like.

A hull skirt on a boat moored next to a wall

A sacrificial skirt stops debris from a rough wall getting onto rotating fenders and scouring the hull. Credit: Gilbert Park

Debris coming off the rough surface may get caught on fenders and then rub on the gelcoat of the boat acting like sandpaper and wrecking the finish.

This can be prevented by using a sacrificial skirt made of strong material and having a set of fenders going against the wall.

It should be noted that if you put a skirt on a boat that has been painted you should put the skirt next to the concrete, not the boat.

If you put it between the fenders and the boat, the paint may blister, even with a two-pack paint.

A blue boat drying out against a wall

This boat shows how to moor against a wall. There is a bow and stern (breast) line and these go up to a pulley. On the other side of the pulley is a weight (old chain and a winch hook in this case) that holds the boat into the wall when it is afloat. Credit: Gilbert Park

A further alternative is to put the fenders on the front of a scaffold plank and then put old carpet on the back of the plank.

This also has the advantage of making hanging the fenders easier.

Because of the potential damage done to the hull by waves, especially when the boat is about to ground, some owners hang weights so the boat dries leaning away from the wall – a full, 40lt flexible water container will do the job.

Securing the boat to the wall so it doesn’t float out at high water can be achieved by using a weight through a pulley attached to a mooring cleat.

Legs

Correcting the list may do nothing to stop forward or aft tilt. Fore and aft guys might also be rigged to stop the legs from rotating. Imagine a motorcyclist stopping on a heavy motorbike.

One leg goes down to the floor as the bike stops and the bike is balanced so that the majority of the weight remains on the wheels with just a little on the leg.

With a boat, the majority of the weight is taken on the centre line keel with only a little on the legs.

A motorboat drying out against a wall

Here’s my boat moved to a neighbour’s wall mooring. Note the bow-down attitude and that the legs are now too short. Credit: Gilbert Park

It’s important the legs are not so long that they take the whole weight of the boat as the hull might otherwise be damaged.

Some boats, especially older ones, may have legs that are wooden and shaped to fit the hull.

A single bolt goes through the hull to secure them. If they fit securely they may not need fore and aft lines.

Metal legs are common and may be fabricated for a specific boat.

A boat with legs drying out in a harbour

Some Scandinavian boats have built-in legs installed on the transom. They are secured in place with a pin. Credit: Gilbert Park

On my boat, I have adjustable ones made by the Yacht Leg and Cradle Company, which has started manufacturing them again after an absence of several years.

These I can adjust to keep the boat reasonably level (a slight list to one side confirms that the keel is taking the majority of the weight).

When my boat is in its permanent mooring, a sloping slip at the side of the house, the legs and the keel sink into the mud.

There are only slight indentations in the mud for the props and the keel and legs have deep indentations.

The boat remains level fore and aft.

Sink or lean

Occasionally I have to borrow a neighbour’s mooring which has a harder seabed.

On this mooring, the legs from my mooring are a little too short than needed and the boat has a considerable list.

Lengthening the legs a few centimetres allows the boat to have only a slight list.

Fore and aft guys are attached to the bottom of each leg to stop them from swinging up.

When recovering a leg, I shake the leg in the water to try and get all the mud off and have a spatula to scrape any remaining off.

A rubber strip being applied to the bow of a boat

To protect the keel on stony seabeds a tough rubber strip can be stuck on. Credit: Gilbert Park

If I bring the legs on board with any mud on them it gets everywhere!

Some new, large boats now come with built-in legs on the transom as an option. These will make drying out a whole lot easier.

Some time ago, I did see a manufacturer who made adjustable wedges to go under the transom of a boat like the Merry Fisher that was inserted just before the boat dried out to keep it level.

I can’t find them now, but it may be possible to duplicate them by using levelling wedges for motorhomes if any reader wants to experiment.

A boat with a blue hull drying out

On different moorings, lengthening or shortening legs a few centimetres can allow the boat to dry level. Credit: Gilbert Park

One top tip: if you do keep your boat on a drying mooring, close the seacocks when the boat is dry if you can. The pipes are then empty of water. This stops marine growth in them. It also prevents the nasty smell you sometimes get in the heads if you do this and then flush the toilet with fresh water from the hand basin.

Just one word of caution. If you’re in an unfamiliar mooring it’s worth feeling around the boat to make sure you’re not on the edge of the channel and don’t dry out at an angle, or there is a block of concrete or a supermarket trolley to damage the boat.

Alternatively, if you have one, use the seabed structure feature on your depth finder to see what’s there.

So is it worth having legs on your boat if you don’t keep it on a drying mooring? The answer is an undoubted yes.

A boat on legs drying out on a river

Wooden legs secured by a bolt may not need guy ropes. Credit: Gilbert Park

It enables you to do straightforward maintenance such as changing anodes on the ‘hard’, rather than lifting out (but please use other supports as well).

Legs also increase the places you can go. In the Solent, there are at least six drying harbours I have stayed in including Ryde, Newport, Wootton Creek and Wootton Bridge on the Isle of Wight.

On the mainland Ashlet Creek, just off Southampton Water, and Keyhaven near Hurst Castle.

All of these share attractive attributes, besides drying out.

On a recent trip to the West Country again they were in use in the Isles of Scilly: anchor, put out legs, wait for the tide to go out and then go for a walk on the sand. Wonderful.


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