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Back in the early 1970’s Mary Johnstone raced 470 class sailboats in the “trapeze” position, often cantilevering herself completely outboard from a masthead wire to keep the jittery, planing 16-footer dry side up. Husband Bob steered, while two of their children raced another 470 and the other two stood by in an outboard in case either team’s weight-versus-wind balancing act went awry.   The
Price $375000.00


Year 2004
LOA 34’0”
Beam 11’0”
Draft 2’5”
Fuel Capacity (in Gallons) 150
Water Capacity (in Gallons) 60


Standard Power 1/440-hp Yanmar 6LY2A-STP diesel inboards
Optional Power 1/315-hp Yanmar 6LPA-STP diesel inboard; 2/315-hp Yanmar 6LPA-STP or 2/440-hp Yanmar 6LY2A-STP diesel inboards
Controls Kobelt mechanical
Weight 10600 pounds
Steering Teleflex Sea Star hydraulic

Back in the early 1970’s Mary Johnstone raced 470 class sailboats in the “trapeze” position, often cantilevering herself completely outboard from a masthead wire to keep the jittery, planing 16-footer dry side up. Husband Bob steered, while two of their children raced another 470 and the other two stood by in an outboard in case either team’s weight-versus-wind balancing act went awry.

The family that flips boats together stays together? If sailboat people do odd things, the scene above is just one of thousands in this family’s illustrious sailing career. Together and alone, the clan has amassed barrels of trophies, not to mention thousands of sea miles, in all sorts of sailboats. Johnstone is the “J” in J Boats. In 1977 Bob—a major marketing career at Quaker Oats already under his belt—and his naval architect brother Rod introduced the J24, an innovative, some said weird, design for racers wanting to go bigger without losing the small boat thrills. The rest, as the saying goes, is history.

Today there are more than 5,000 J24s sailing in fleets around the world, a total of 10,700 J Boats in 32 racing and cruising designs up to 53 feet. The brothers Johnstone still conceptualize/design new models, but a team from the second generation manages the company day to day. Mary’s retired from racing, Bob not quite, and over the last decade their time together on the water has been mostly enjoyed aboard a series of classic Dyer 29 inboards (which they fiddled with, as seen in Dyer’s DownEast model). In the normal course of things, this couple might now be enjoying an active retirement aboard one of those handsome semicustom power cruisers—think Hinckley, Legacy, Eastbay, etc.—that older Yankee sailors seem to favor.


Nah. Instead, the Johnstones dreamed up their own fairly audacious notion of a fun 34-footer and then created an all-star team to build her in volume and market her. While the couple has already enjoyed gunkholing around Maine on Hull No. 1, Grace, the boat also toured the season’s East Coast shows, including an October stop in Annapolis where I tested her. And while the vessel may be known affectionately in the family as Mary Johnstone’s Motorboat, marketing guru Bob hopes the simple, symmetrical “mJm” which fits neatly on a cove stripe or boating cap, is destined to become another widely seen J logo.

Like the original J24, the MJM 34Z will not be confused with any existing designs. Look how the bow flare and slightly reversed sheer of a Carolina offshore fishing boat twists into the sort of aft tumblehome that’s become a signature of New England lobster yachts. Yet the pilothouse, open as a porch with its straight up-and-down side windows and support post, is pure modern lobster boat, not yacht. Ayuh, with the Strata Glass side curtain rolled up, you could haul pots from the helm, or pick up a mooring, or—like a solo fisherman—step right from the wheel onto a float to tie up. Note that soft- and hardtop express versions—even a sportfish configuration—are available, but all the early buyers have chosen this Down East model.


My boat gut is still not sure how it feels about the overall aesthetic of this hybrid concept, as gracefully drawn out as it was by architect Doug Zurn (the Z in 34Z). But in as much as form does follow function in a good boat, I think, the MJM appears to be sensible indeed. That porch-like house is not just practical, it’s also a wonderfully open place to drive or just hang out with friends. The flare not only results in a dry boat—dry as toast, even sitting on the stern seat at speed through Annapolis’ crazy outer harbor wakes—but also gives the forepeak table/berth area a spacious feel. Sit at that table, and you’ll notice how good-size ports fit just below the sheer at perfect eye level and can even be left open in rainy weather because of the overhang.

I’d call those ports a cherry-on-top feature, one of many, except that the real cherry is in the light, lustrous joinery work that surrounds this lovely cabin, suitable for cocktails for six or a long weekend for two. The cockpit and pilothouse are equally flexible people places, and moving anywhere, including the bow, you’ll find a well-thought-out path. It’s easy to imagine the Johnstones—after all those years of tight sailboat cockpits and spider-webbed decks—gleefully maximizing ergonomics on the 34Z. They also detailed the topside areas in a more utilitarian, low-maintenance style than some might like, but teak soles and a teak pilothouse table are available options. Otherwise, the list of standard gear is remarkably complete and well chosen.

The Johnstone attention to detail is also obvious in the stainless steel handholds that are in all the right places; huge pilothouse lockers with room enough for bikes, but also with mesh pockets for organizing small gear; and deck drains so that rain won’t stain the topsides. Notice the mate’s station with its own Stidd chair and a place for paper or laptop charting, with power and GPS hookups built in; there’s plenty of electronics power at the helm for singlehanding, but sharing navigation can be really fun in explorer mode, extra safe in fog mode.

The MJM’s combination of hull form—the flare, relatively narrow beam, and a long run of constant 18-degree planing surface—plus a super-light and super-strong construction program promise high performance (and low fuel consumption), even with modest power. The hull certainly seems bulletproof; its epoxy/Kevlar/core laminates are vacuum-bagged and oven-cured at high-tech Boston Boatworks. And the test numbers indicate an efficient, nimble craft, even though the prop—which, by the way, is pocketed to reduce draft—was still being tweaked and the Yanmar couldn’t wind up to its maximum 3300 rpm.

The 34Z did pop onto plane quickly, assuming an almost constant running trim that felt just right, with excellent visibility at the helm. Sound levels, even standing nearly atop the diesel, were not bad. Handling was tight, light, and sporty, and I sensed that the boat would continue to behave well even in serious sea conditions. Altogether, the MJM 34Z asks for, and deserves, a second look. Just don’t be shocked when you seek out your local dealer and find yourself in a forest of J Boat masts; this powerboat’s parents were sailors.


The Boat

Standard Equipment

Northstar 6000i chartplotter/radar; Icom M-502 DSC VHF; Raymarine ST60 depthsounder; Side Power SP55S bow thruster; Link 2000 battery controller; Freedom 30 Heart interface/charger; Bosworth manual bilge pump; VacuFlush MSD; Panasonic s/s convection/microwave oven; Princess ceramic cooktop; 5-cu.-ft. top-loading refrigerator; Seagull water purifier; Samsung LCD TV; Clarion stereo w/XM Satellite receiver, CD changer, 400-watt amp, and 4/speakers; Lewmar 33-lb. s/s claw anchor with s/s chain and nylon rode

Optional Equipment

3.8-kW Westerbeke genset; 16,000-Btu Marine Air reverse-cycle A/C; teak pilothouse sole & double-leaf table; Raymarine 6001 autopilot

The Test

Test Boat Specifications

  • Test Engine: 1/440-hp Yanmar 6LY2A-STP
  • Transmission/Ratio: ZF 80-1 A 8-degree down-angle/1.20:1
  • Props: 20x21 Hall & Stabert w/cup
  • Price as Tested: $399,500

This article originally appeared in the May 2004 issue of Power & Motoryacht magazine.

The Photos