Buying a used boat or jet ski: the hull, the engine hours and the paperwork before summer

Every October the same listings turn up. A runabout on its trailer in a driveway, photographed from its good side: “always garaged, runs well, ready for summer”. A jet ski with the cover half off. A tinnie whose motor, according to the seller, “just needs a run”. Summer is six weeks away and half the country has remembered it wanted a boat.

Some of those listings are good buys. Others are the old joke about the two great days of boat ownership, the day you buy it and the day you sell it, except this time you’re the buyer on somebody else’s second great day. The difference usually comes down to what you check at the inspection, and the order you check it in. The checklist below is the inspection-day version. Take it with you on your phone. The rest of the article explains each line.

Three purchases in one

It helps to stop thinking of it as one purchase. A trailer boat is really three: the hull, the engine and the trailer it sits on. A jet ski is the same idea, with the engine and pump tucked inside the hull and a trailer underneath. Each of the three ages in its own way, and each can fail without the other two.

A sound hull with a tired motor is a project. A good motor on a hull with a soft floor is a different project, and usually a dearer one. A tidy boat on a trailer that has rusted through won’t make it to the ramp. Sellers tend to talk up whichever of the three is in the best shape, which is understandable, and not much use to you.

So look at each part as if it were its own listing. Then add the paperwork, which is the fourth thing and the one most likely to cause trouble long after you’ve towed it home.

Do the land checks first, with the boat sitting on its trailer, and leave the water test until last. If it fails something in the driveway, you’ve saved yourself a morning at the ramp. Go in daylight, too, and on a dry day if you can. A wet hull hides cracks nicely, and a torch at dusk is nobody’s idea of an inspection.

The hull

Start underneath, because that’s where the problems hide. With the boat on the trailer you can see most of the hull, and a torch does the rest.

On fibreglass, go over the gelcoat, the hard glossy outer layer, looking for cracks. Pay attention around fittings and anywhere the hull would flex when it hits a wave. Patches that are a slightly different colour or texture from the rest usually mean a repair. A repair isn’t a reason to walk away on its own, but ask what happened and who did the work. Then walk around inside and press on the floor and deck with your weight. Soft spots, or a floor that gives underfoot, are worth taking seriously.

On aluminium, check the welds and rivets for cracks, and look for corrosion, which tends to show as pitting or powdery patches. Dents along the keel tell you it has met a sandbar or two.

The transom is the flat panel across the back that the outboard hangs off, and it carries a lot of load. Get someone to push and pull on the motor while you watch the transom. It shouldn’t flex. Look around the mounting bolts for rot or darkened timber where the construction has any.

Lift the hatches and look in the bilge. It should be close to dry and shouldn’t smell of much. A pool of dirty water, or a smell of oil or fuel, is a question for the seller.

For a jet ski, the underside of the hull matters most. Look for deep gouges and cracks from beaching. Check the intake grate underneath, where the ski draws in water, and look up into the pump and impeller area for chipped or bent parts. Weed and rope get sucked in there, and so does the odd rock.

The engine: cold start and hours

When you arrange the inspection, ask the seller not to start the engine before you arrive. Say it plainly, and say it again the day before. A cold engine tells you far more than a warm one. Hard starting, smoke and a rough idle often settle once a motor has warmed up, which is exactly why some sellers like to have it “warmed up and ready” when you pull in. Put your hand on the motor when you get there. If it’s already warm, ask why.

An outboard on land needs water supplied to it while it runs, so let the seller set that up. It’s their motor, and if something goes wrong it’s better their hands are on it.

Watch and listen as it starts. It should fire without endless cranking, settle into a steady idle and not pour out heavy smoke. A puff on start-up can be normal on some motors. A cloud that doesn’t clear isn’t. On an outboard, look for the tell-tale, the small stream of water that comes out of the motor to show cooling water is moving through it. If it’s weak or missing, that’s worth asking about.

Then the hours. Many boat engines have an hours meter, and jet skis usually show hours on the display. There’s no magic number that makes hours good or bad, whatever the forums say. What matters is that the meter, the service records and the seller’s story all agree. A motor with plenty of hours and a regular service history can be a better bet than one with few hours that sat under a tarp for years. If there’s a logbook, read it. If there are receipts, look at the dates and who did the work, and see whether the gaps between services line up with how the seller says it was used. A boat that “only went out a few times a year” and a stack of receipts from the same few months each summer tell the same story, which is what you want. If there’s nothing at all, factor that in. Plenty of honest owners keep no records, but you’re the one taking the risk on their memory.

The best test is in the water. A motor that idles nicely on the trailer can still struggle under load. If the seller will meet you at a ramp, take it out and see how it behaves at speed. If a water test isn’t on offer, or you don’t know engines, book a marine mechanic to look it over. It isn’t free, but it’s the cheapest part of buying a boat that turns out to be wrong.

The trailer

The trailer is the part people forget until it’s on the side of the highway with a smoking hub.

Start with the paperwork. A boat trailer has its own registration, so check the rego is current and the papers match the trailer in front of you. The checks are much the same as for any vehicle bought privately, and our guide to buying a used car from a private seller covers the registration and ownership side in more detail.

Then walk around it. If you can get a wheel off the ground, spin it by hand. It should turn smoothly and quietly. Grinding, or a wobble when you rock the wheel, points to the bearings. Look at the tyres for cracking as well as tread.

Check the rollers or skids that the hull rests on. They should all be there, and rollers should turn. Try the winch: it should wind in and out cleanly, and the strap or cable shouldn’t be frayed. Plug the lights into your car and check every one, indicators and brake lights included.

Bigger trailers need brakes, depending on their weight and your state’s rules. If this one has them, ask when they were last looked at.

Finally, get down and look underneath at the springs and the frame. Salt water is hard on steel, and rust in the springs or along the frame is common on a trailer that has been backed into the sea for years.

Paperwork and the PPSR gap

This is where buying a boat differs most from buying a car, and where careful buyers still get caught.

A boat should carry a hull identification number, or HIN, or an official number. Find it on the boat itself and check it matches the registration papers exactly. A number that’s missing, scratched or doesn’t match is where the inspection ends.

Next comes a PPSR search. The Personal Property Securities Register is where lenders record an interest in goods that money is owed on. For a boat, you search by the HIN or the official number. According to the PPSR’s guidance on buying a boat, a watercraft search won’t return a description of the boat, so it can’t confirm that the boat in front of you is the one on the papers. It also won’t show whether the boat has been reported stolen.

And there’s a bigger gap. An outboard motor can’t be searched by its engine number. If the seller borrowed money against the motor, that finance may not show up on your search at all. The hull can come back clean while the motor still has a lender attached to it. So ask the seller, in writing, whether anything is owed on the outboard, and keep the reply.

Boat registration rules vary by state, so check what yours needs for a transfer. Then get a receipt with both names, the HIN, the engine serial number and the price. Our guide to private-sale fine print covers what the receipt should say and how a rego transfer works.

One last thing on money. Don’t pay a deposit on a boat you haven’t seen. “Someone’s coming to look tomorrow, but I’ll hold it for you” has cost a lot of people a deposit on a boat that never existed. Our rundown of marketplace scams in Australia goes through how that one works.

The licence before the water

If the plan is to drive it home on the water rather than tow it, you’ll need the right licence first, and you’ll need it anyway before the first proper outing.

In NSW, according to the NSW Government, you need a licence to drive a recreational vessel at 10 knots or more, and to drive a personal watercraft, such as a jet ski, at any speed at all. The general boat licence comes first, and the PWC licence comes after it. Licences are available from age 12. Under-16s have restrictions: no more than 20 knots, no towing, and no driving between sunset and sunrise.

That catches out the person who has driven a tinnie for years and buys a jet ski for the kids. The boat licence they’ve got doesn’t cover the ski on its own.

Other states run their own systems, and the rules differ. Check with your state’s maritime authority before you buy, not after. If you’ll need a course or a test, it’s better to know in October than to find out on the first hot weekend with the boat sitting in the carport.

While you’re at it, check the safety gear that comes with the boat. Lifejackets should be there and in good condition, and flares, where they’re required, should be in date.

Start it cold, search it twice

A used boat is three purchases and a folder of paperwork. Look over the hull out of the water. Start the engine cold, then compare the hours with the records. Check the trailer as if you were buying it on its own. Match the HIN, run the PPSR search, and ask in writing about finance on the outboard, because the search won’t show it. Sort the licence before the first run. If there’s anything you can’t judge yourself, pay a marine mechanic to judge it for you. Do all that, and with any luck the two great days come with plenty of good ones in between.

Sources: NSW Government, Get boat or personal watercraft (PWC) licence (https://www.nsw.gov.au/driving-boating-and-transport/maritime-licences/boat-and-pwc-licences/get-boat-or-pwc-licence); PPSR, Buying a boat (https://www.ppsr.gov.au/searching/do-boat-search)