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How to Upgrade Your Boat Like a Pro

Now Hear This

Wanna make that boat of yours better?

Check out what the vice president of sales and marketing for the largest custom superyacht builder in the United States has done with his 30-year-old old Mainship 34 Mark II trawler.

Billy Smith

So it’s six or so years ago, and I’m just leaving the charming little Pass Christian Yacht Club, which hovers on hurricane stilts above the coastal sands of Pass Christian, Mississippi, when, off to the west, a proud, delicately raked stem, ornamenting the business end of a Down Easterly-looking profile, catches my eye. Immediately overcome by momentary hypnosis, I veer off, proceed through the gate of the little marina that adjoins the club, start hoofing it down the dock, and just keep on truckin’ until I eventually reach the stern of the vessel that has so radically captured my attention. 

Wow! Looks like she’s a Mainship 34 Mark II, a classic motor cruiser (although everybody called her a trawler back in the day) that the Luhrs Mainship Corporation ceased building back in 1983 [see: “Not Your Grandfather’s Mainship,”]. But hey, despite her vintage, she appears to be new—and I do mean new! Her flag-blue hullsides shine flawlessly with sun spangles. Her gleaming arctic-white superstructure engenders a smart, almost startling, contrast. And a silky sunshade overhangs the cockpit, elegantly wafting in the breeze, supported by shiny, custom-made aluminum poles emanating from rod holders.

Not Your Grandfather’s Mainship

Mainship 34 Mark II

Two years ago, boatbuilder David Marlow bought the assets of Mainship and Luhrs Corporations, founded Marlow-Mainship Trawlers, and introduced a pretty little 32-footer. Given the general enthusiasm attending these developments, it’s quite possible that Marlow’s new line of trawlers will be at least as popular as this lovely old girl above, Smith’s classic 34 Mark II Motor Cruiser.

“Man, that’s a helluva boat,” I enthuse, as a bewhiskered gent clomps past in a pair of beat-up shrimp boots. “Know who owns her?”

“Name o’ Billy Smith,” he replies. “Member o’ the club.”

“Not the Trinity Yachts guy?” I ask, a tad blown away. Is it possible that I, while pursuing a completely unrelated venture, have stumbled across an old, well-loved, 34-foot, single-engine trawler belonging to William S. (Billy) Smith III, vice president of sales and marketing for Trinity Yachts, arguably the largest custom builder of superyachts in the United States? After all, Trinity Yachts is not far off. The shrimp-boot gent just keeps on clompin’, uttering nary a word.

So, A Guy Goes Into A Boatyard

Many moons go by. My wife BJ and I are just finishing off an alligator-sausage appetizer at the Back Bay Seafood Restaurant, not far from Trinity Yachts shipyard in Gulfport, Mississippi, and we’re in excellent company. As a waiter offloads steaming bowls of crawfish etouffee as a sausage chaser, Smith smiles broadly,  allowing as how he’s flattered we’ve taken the trouble to ask around and confirm his ownership of the gorgeous little Mainship in Pass Christian. Then he tells how he acquired the boat, some ten years earlier.

“You know, I was a member of a sailboat racing syndicate for a long time,” he begins. “We had a three-quarter-tonner and had an absolute ball with it. The SORC, Newport-Bermuda, Miami-Montego Bay, Sardinia cup, the St. Petersburg-Isla Mujeres races—I’ve competed in ’em all. But now I wanted somethin’ different—a powerboat.”

Smith had his share of must-haves. For starters, he wanted a “Down East, lobster-boat look, like a mini-Bruno Stillman.” And then he wanted several other features, most notably single-diesel propulsion (for fuel economy), an air-conditioning system synergized with a diesel generator (for summertime anchoring), a separate shower stall (to obviate mold, mildew, and other issues associated with wet heads), a lower helm station as well as an upper (to facilitate all-weather operation), and, last but not least, a top speed in the 18-knot-plus range.

“So I go into this little boatyard up in Slidell, Louisiana,” Smith says, “and there she is—under a tarp, with an unpaid yard bill. One of the naval architects from Trinity drives up to check ’er out for me and he concludes from lookin’ at her bottom she’ll hit 20 knots easy. Sold!”

Smith fields a call

While buttoning her up Smith fields a call from Dubai? Paris? Singapore perhaps?

The Incredible Sliding Genset

Mostly because paying for replacement components and service for the old Mainship’s 200-horsepower Perkins diesel was “stupid expensive,” but also because he wanted to add an extra 5 knots or so to the boat’s top end, Smith sold the old Perk for parts and ordered up a rebuilt 315-horsepower Cummins 6BTA-5.9 diesel from his buddy Rob Casadaban of Casadaban Marine Services in Slidell. “I made way more money selling the Perkins that way,” he says. “In one piece, she wasn’t worth a whole helluva lot.”

While awaiting the Cummins’ arrival, Smith took Casadaban’s advice and added a new ZF 220A marine transmission with a 2.04:1 gear ratio, considerably deeper than the 1.5:1 ratio in the unit Luhrs Mainship had originally installed. “Yeah, I was gonna lose a little speed with the deeper gear,” Smith explains, “but Rob told me it’d be more forgiving—it’d keep me on plane whether I had two people onboard or a dozen.”

The empty and expectant cavity in the Mainship’s temporarily engineless engine room got Smith to thinking. One of the Mark II’s drawbacks was her puny 50-gallon freshwater tank, mounted in the lazarette. What if he yanked the darn thing out and substituted two 50-gallon cross-linked poly saddle tanks farther forward, just outboard of where the new engine was destined to go? And then, what if he relocated the 4.5-kilowatt Westerbeke generator from the engine room (where it inconveniently obfuscated the prop shaft and shaftlog) to the now vacant spot in the lazarette. Not only would the maneuver do away with a leaky old undersized tank, it would double the boat’s freshwater capacity, and stretch the distance between the Westerbeke and the only sleeping arrangements onboard, up forward in the V-berth stateroom.

“But get this, Bill,” enthuses Smith, with a Cheshire-cat grin. “After I did all this stuff, I went ahead and installed tracks made of aluminum angle so the plywood raft the genset sits on can slide aft into the open area under the lazarette’s hatch—gives me complete, 360-degree access for maintenance!”

Put ’Em On Steroids, Man

Before the Cummins was lowered onto its new, custom aluminum engine mounts (fabricated by a couple of moonlighting Trinity welders), Smith decided to make a couple of further modifications, starting with the addition of a crash pump. “We simply spliced a ball-type Y-valve into the raw-water feed for the engine,” he explains. “So now, using the engine as a pump, I can pull from outside the boat or, in an emergency, from inside.”

The fuel system came next. Smith replaced the original single Racor FG200 fuel-water separator for the main engine with two giant, duplex Racor 751000MAs, each overqualified to handle the fuel supply. “You see these little Racors on some of these boats these days,” Smith opines. “Why not go bigger—like way bigger? Worried about pluggin’ up your Racors? Put ’em on steroids, man!”

Aesthetics, Etc.

While Smith’s many additional engine-room and related upgrades were virtually invisible to marine-grade aesthetes and other compulsive dockwalkers, the next set of projects were anything but. The Mainship’s hull was faired and painted flag-blue with Dupont polyurethane, a classical color nicely set off by a fire-engine-red bootstripe. The white superstructure was faired and painted with poly as well, and the bottom was carefully barrier coated and then bottom painted with Interlux Intersleek, a pricey formulation that relies on slipperiness to nix marine fouling, not biocides or copper. “The last application was five years ago,” Smith says, “and the stuff is still workin’ great.”

Other aesthetically pleasing tweaks? Old deck hardware was replaced with extra-beefy stainless steel componentry, all of it undergirded with backing plates and/or fiberglass-laminated mounting blocks of Norplex Micarta, a high-performance, super-strong composite. “I anchor the boat during hurricanes,” Smith says, “and I don’t want my Sampson post to fail or any of the cleats.” Moreover, a Side-Power electric thruster was added, with controls at both upper and lower helm stations. “You only need it when the wind gets up,” says Smith, “but then it’s invaluable.” And new electronics were installed, including a couple of Garmin GPS plotters, two ICOM VHFs,  and a kick-back Raymarine ST6002 autopilot.

Truth At Sunset 

It’s the end of a perfect day. The three of us are taking a breather in the saloon of Smith’s sweet little Mainship, after a long, in-depth tour. Smith sits proudly at the lower helm station in a rather unusual helm chair, a movable director’s type with extra-long legs to ensure solid sightlines over the bow throughout the rpm range. Yet another of his addendums.

“So look here, guys,” says Smith, handing over an ensign staff fitted with a finely-machined rod holder-compatible base. “You don’t need a separate fitting for your ensign on this boat—just use a rod holder. Makes sense, eh?”

As I examine the staff appreciatively, I’m constrained to marvel: Is there anything Smith could do to further upgrade this lovely old Mainship? I mean anything?

“O’ course I’ve got a few other projects on the back burner,” Smith says, evincing a wild and unexpected flair for clairvoyance, “Like enlarging the rudders—so she’ll steer better in a following sea. And adding a dripless shaftlog—to keep the bilges cleaner. Maybe I’ll even widen the chines. Who knows?”

BJ, who’s been married for decades to a total boatnut with plenty of back-burner preoccupations of his own, smiles ruefully as the sun sets in the west. “You two guys,” she observes, looking from one cheery face to the other, “are a lot alike.”

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  • Builder: Mainship
  • Model: Mainship 34 Mark II

This article originally appeared in the January 2014 issue of Power & Motoryacht magazine.