21' SeaChaser — Marathon’s nimble runabout for fishing, diving and island days

MARATHON BOAT TOUR FIELD GUIDE

21' SeaChaser — Marathon’s nimble runabout for fishing, diving and island days

A comfortable, fuel-efficient SeaChaser with seating for 6–7, a single Yamaha F225 engine, Garmin fishfinder and a large transom live well, offered as 1–4 week rentals from Marathon.

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21' SeaChaser — Marathon’s nimble runabout for fishing, diving and island days.

Duration
1-4 Week rentals
Location
Marathon
Operator
Marathon Boat Rentals Inc
Category
Boat Tour
Robert Eric Crews
Founder & Editor, The Adventure Collective
Published Verified

Set sail from Marathon aboard a roomy 21' SeaChaser built for inshore fishing, diving and short island excursions. The Offshore Series model is designed to be sturdy and comfortable: ample seating for six to seven people, integrated Garmin GPS with fishfinder, a large transom live well and a fusion audio head unit, with all required safety equipment furnished by the operator.

Highlights

Outing Highlights

Purpose-built, user-friendly runabout
THE BOAT

Purpose-built, user-friendly runabout

The SeaChaser Offshore Series pairs a stable hull with practical systems for day use — seating that fits six to seven people comfortably, a big transom live well for anglers, Garmin navigation and fish-finder electronics, and an onboard audio head unit. The operator provides the necessary safety equipment with each rental.

Fishing, diving and island hops
THE USES

Fishing, diving and island hops

Whether you’re setting lines inshore, dropping in at a favorite dive patch or cruising to a nearby island to anchor and relax, the SeaChaser is marketed as a versatile platform for fishing, diving and island adventures around Marathon.

Single-engine reliability and economy
PERFORMANCE

Single-engine reliability and economy

Powered by a single Yamaha F225 four-stroke, the SeaChaser balances reliable power with fuel efficiency for longer days on the water — a practical choice for small groups looking to spend hours or multiple days exploring local waters.

What the day feels like

What the day feels like

The outing is straightforward and adaptable: load gear and people, punch past the flats or slip into calmer inshore lanes, let the Garmin guide you to fishable structure or anchor off a small island for a swim or shore visit. The SeaChaser’s layout and systems are tuned to make short expeditions — fishing, diving or leisurely cruising — smooth and predictable.

Purpose-built, user-friendly runabout

THE BOAT

Purpose-built, user-friendly runabout

The SeaChaser Offshore Series pairs a stable hull with practical systems for day use — seating that fits six to seven people comfortably, a big transom live well for anglers, Garmin navigation and fish-finder electronics, and an onboard audio head unit. The operator provides the necessary safety equipment with each rental.

Fishing, diving and island hops

THE USES

Fishing, diving and island hops

Whether you’re setting lines inshore, dropping in at a favorite dive patch or cruising to a nearby island to anchor and relax, the SeaChaser is marketed as a versatile platform for fishing, diving and island adventures around Marathon.

Single-engine reliability and economy

PERFORMANCE

Single-engine reliability and economy

Powered by a single Yamaha F225 four-stroke, the SeaChaser balances reliable power with fuel efficiency for longer days on the water — a practical choice for small groups looking to spend hours or multiple days exploring local waters.

Suitability

Who it's for

Who this boat suits — and who should look elsewhere.

1
Small groups and familiesComfortably seats six to seven people, making it a good fit for family outings or small groups wanting to split time between fishing, swimming and island stops.
2
Anglers and dive teamsEquipped with a large transom live well and Garmin fishfinder, the boat is tailored to small angling or diving parties operating together.
3
Day-trippers and island hoppersThe SeaChaser’s seating and onboard audio make it suitable for short recreational cruises and island visits for groups that fit within the seven-person limit.
4
Large groups or charter operationsNot ideal — the vessel’s maximum accommodated party is up to seven people, so larger groups should consider multiple boats or a larger charter.

Practical planner

Details to review before reserving

What to Bring

The operator provides all necessary safety equipment with the rental; confirm any personal items you prefer to use (personal flotation devices beyond the provided, dive/snorkel gear or fishing tackle) directly with Marathon Boat Rentals.

Booking Lengths

Rentals are offered in 1–4 week blocks, enabling short escapes or longer stays depending on your plans.

Onboard Systems

The boat includes Garmin GPS with fishfinder, a fusion audio head unit with speakers, and a large transom live well as standard equipment.

Booking Notice

Review cancellation policies before reserving.

Frequently asked questions

Planning Your Outing

How many people can the 21' SeaChaser hold?

The SeaChaser has seating for six to seven people and is advertised for groups up to seven.

What engine powers this boat?

The SeaChaser Offshore Series is powered by a single Yamaha F225 225hp four-stroke engine.

How long can I rent the boat?

Rentals are available in durations of 1 to 4 weeks.

Is safety equipment included?

Yes — all necessary safety equipment is provided with the rental.

What onboard features are included?

The boat comes with Garmin GPS and fishfinder electronics, a large transom live well, and a fusion audio head unit with speakers among its standard features.

What kinds of trips is this boat suited for?

The SeaChaser is presented as suitable for inshore fishing, diving and island adventures, and can also be used for offshore fishing expeditions.