Marine Services on Lake Winnipesaukee

Outboard Motor Repair and Service, Lake Winnipesaukee

Outboards take the brunt of a short northern season. They sit for six months, then get asked for full power on the first warm Saturday in May. A lot of outboard failures on this lake trace back to that pattern rather than to hours on the clock.

Lower Unit and Gearcase Service for Lake Winnipesaukee Boats

Think of the lower unit as the bit of the drive that lives underwater — gearset, prop shaft, seals, and the oil keeping all of it alive. It fails quietly. Gear lube goes milky, a bearing starts to whine, and a month later it's a much bigger job. Mainline Marine Service pulls, inspects, reseals and rebuilds lower units at the shop in Mirror Lake.

Propeller Inspection, Hub Diagnosis and Replacement on Lake Winnipesaukee

A damaged prop does two jobs badly. It quits pushing the boat properly, and it shakes everything behind it. Bent blades? A spun hub? Maybe just the wrong pitch? You pay in speed and fuel first, then, sooner or later, in seals and bearings. Mainline Marine Service pulls props and looks them over, finds spun hubs, checks the shaft and the seal after you've hit something, and puts the right replacement on. Straightening, re-pitching and balancing go to a specialist prop shop, a trade partner.

Cooling System Repair and Overheating Diagnosis on Lake Winnipesaukee

Marine engines don't have a radiator. They pump lake water through themselves and spit it back out, and the whole setup hangs on one rubber impeller doing its job. When that goes, a temperature alarm might be your only warning, and there isn't much time between the alarm and real damage. Mainline Marine Service diagnoses and repairs cooling faults at the shop in Mirror Lake and mobile around the lake.

Fuel System Service and Contamination Repair on Lake Winnipesaukee

Most engines that won't start in May were running perfectly in October. Nothing broke over the winter. The fuel changed. Pump gas in most of the US has up to 10% ethanol in it, ethanol soaks up water, and six months in a half-empty tank is plenty of time for that to turn into a real problem. Mainline Marine Service cleans, repairs and remediates fuel systems at the shop in Mirror Lake and at the dock.

Personal Watercraft Service on Lake Winnipesaukee

A personal watercraft has no propeller. No lower unit, no gearcase oil to change. It has a pump, an impeller and a wear ring, and nearly everything that goes wrong with performance comes back to those parts and to whatever the intake swallowed. We service Sea-Doo and other personal watercraft at the shop in Mirror Lake, NH, and we winterize them alongside jet boats.

Mercury Outboard and MerCruiser Service, Lake Winnipesaukee

Mercury shows up on Lake Winnipesaukee in two forms that share a badge and not much else. Outboards hanging off a transom. And MerCruiser sterndrives buried under the sun pad of a bowrider. They get serviced differently, they fail differently, and the parts that wear aren't the same. We work on both, at the shop in Mirror Lake and mobile at docks around the lake.

Yamaha Outboard Service on Lake Winnipesaukee

Yamaha four-strokes run so quietly that owners forget they're there, and that's exactly how a boat ends up three seasons behind on service. On Lake Winnipesaukee the range goes from small portable kickers all the way up to the big V6 and V8 offshore engines on center consoles and large bowriders, often in pairs or triples. The big ones are more engine. Not just a bigger version of the same service.

A sterndrive puts the engine inside the boat and the gearbox outside it, and the joint between them is the part that matters. On Lake Winnipesaukee the sterndrive is the cruiser and big-bowrider engine. A Volvo Penta under the sun pad, a drive on the transom, and a set of rubber bellows nobody thinks about until there's water coming into the bilge.

Boat Repowers on Lake Winnipesaukee

A repower is the biggest single job most boats ever get. And it starts with a question people skip: is the old engine really finished? Settle that first. Then the work is picking the right engine for the boat and fitting it so the whole rig works as one.

MerCruiser is Mercury's sterndrive line, and you'll find it behind plenty of runabouts, bowriders and cruisers. An I/O is really two machines working together, an inboard engine plus an outdrive on the transom. Most MerCruiser trouble is about where those two meet.

Boat Electrical Repair and Wiring, Lake Winnipesaukee

Boat electrics fail differently from car electrics. Everything lives in damp air, vibrates all season, and is joined by connections that corrode from the inside out — so the fault is usually somewhere nobody has looked rather than in the component that stopped working.

Marine Electronics and Accessory Installation, Lake Winnipesaukee

An accessory's only as good as the circuit behind it. Tap a plotter off the courtesy lights and it'll behave on the trailer — then brown out the minute you're up at cruise. So the real work of an install is where the power comes from, and how that run's protected.

A boat battery fails in a way a car battery rarely does. It sits unused for six months in the cold, comes back weak, and is then asked to crank a cold outboard on the first warm Saturday in May. Mainline Marine Service tests batteries and the charging circuit behind them, at the shop in Mirror Lake or at your dock on Lake Winnipesaukee.

You should never have to think about your steering. When the wheel goes heavy at the dock, binds at full lock, or turns a little before the engine follows, something's already failed or it's close. We service, adjust and replace cable steering, hydraulic steering, and throttle and shift cables, at the shop in Mirror Lake and mobile around Lake Winnipesaukee.

Your bilge pump is the one system on the boat that has to work when nobody's aboard. It's also the one most often found dead right when it's needed. A float switch jammed with junk. A fuse nobody replaced. A hose that's slipped off its barb. We fit and properly test bilge pumps, float switches, hoses and fittings, and we trace leaks back to wherever the water's actually getting in.

A boat lift does one slow, heavy job over and over, standing in lake water. When it starts struggling it usually warns you first. A cable that looks furry. A winch that grinds. A boat that doesn't sit level anymore. Mainline Marine repairs light-duty aluminum boat and jet-ski lifts right where they stand, at your dock.

On a lake boat, aluminum's everywhere — pontoon tubes and their brackets, little fishing boats, lifts, ladders, rails and trailers. Light, sure, and it won't rust. But flex it and it cracks; hit it and it bends. Welding it is part of the service.

The trailer is the part of the boat nobody services until it strands them on the shoulder with a smoking hub. Bearings, brakes, lights and bunks are a short job in the driveway and a very long one at the side of the road — and a trailer that is dunked in the lake twice a year needs more of it than most.

Mobile Marine Mechanic on Lake Winnipesaukee

Most of what goes wrong with a boat goes wrong where the boat is. So Mainline Marine comes to the dock, the mooring or the marina, tools and diagnostic gear in the van. Nobody has to trailer the boat anywhere before somebody can even tell you what's wrong with it.

Marine Engine Diagnostics for Lake Winnipesaukee Boats

Hard starting, overheating, a loss of power at the top end, an engine that runs rough at idle and smooths out at speed — these are symptoms, not faults. Diagnostics is the part of the job that turns a symptom into a part number.

Pre-Purchase Boat Inspections on Lake Winnipesaukee

Buying a used boat on this lake usually goes like this: a quick look on a trailer, a seller who's sure it ran fine in October, and a deposit. A pre-purchase inspection puts numbers behind all that. Compression on every cylinder. Gear lube in a clear jar. A battery under load. And the engine run hard on the water before any money changes hands.

Routine Boat Maintenance for Lake Winnipesaukee Owners

Annual service is the least expensive thing on a boat. It is a short list of parts and an afternoon, and it is what stands between a normal season and a tow back to the ramp on the Fourth of July.

Boat Winterization on Lake Winnipesaukee

Winterization on this lake is not a formality. Water left in a block, a manifold or a raw-water pump on a January night in New Hampshire doesn't freeze politely. It splits castings, and a split block is an engine, not a repair.

Spring Commissioning and De-Winterizing, Lake Winnipesaukee

Ice-out is the starting gun and everybody hears it at once. The boats that go in first are the ones that were commissioned before the ramp got busy — and the ones commissioned properly are the ones that do not come back off the water in June.

Shrink Wrapping and Winter Storage Prep, Lake Winnipesaukee

A boat coming out for a New Hampshire winter has to get through snow load, five or six months of freeze-thaw, and whatever drops out of the pine trees above it. Shrink wrap handles all that far better than a tarp. Only if it's framed right and vented, though. What we do is the prep for shrink-wrap or covered storage — drain plugs out, inside made ready to be sealed up.

Boat Haul-Out and Launch on Lake Winnipesaukee

Getting a boat into the water in spring and out of it in the fall bookends the whole season on Lake Winnipesaukee. Done together with spring commissioning and winterization, it turns two appointments into one — and it is where two of the most avoidable mistakes on the lake happen.