Shamrock 20
By Andy Adams
A full-keel inboard with high power pizazz.
It was love at first sight. You can only stay excited about carpeting and tuck-and-roll upholstery for so long before you start looking for a good, honest boat. But there it was, the Shamrock 20, vaunting its salty charm at the Toronto International Boat Show.
From its tough little pilothouse to its full-length keel, it’s an unusual boat to say the least. Shamrock’s designers probably never meant to appeal to a wide range of buyers but the Cape Coral, Florida plant is running overtime shifts to keep up with demand. The fact is, this may look like a quaint little workboat but it has the power to perform like a flashy runabout or a Coast Guard cutter, depending on the weather.
The boat I tested was the pilothouse model, because early in June this was the only model that had been imported. No matter; it was my first choice anyway. For an owner who wants something that looks more like a pleasure boat, there are three other models: a full cuddy cabin, a runabout type with a walk-through windshield, and a centre console open deck model. But with this boat, it’s the hull that matters.
Above the waterline it has a full bow, hard chines carried all the way forward, and a wide transom. Underwater, the profile line is picked up by the keel at about a quarter of the waterline length aft of the bow and is extended gradually downward to the point of maximum draft at the aft tip of the skeg. There’s a long cut-out to allow free water ahead of the prop and the shaft runs through a strut that connects the skeg to the bottom. The shaft is stainless steel and the prop and rudder are bronze.
The keel is a unique design feature in today’s pleasure-craft market but its construction is unique too. When the hull is laid up, the keel is filled with a composite of granular marble, silica and polyester resin. Tough. I understand that if you really wanted to, you could run the Shamrock at full tilt onto a beach and back it right off again. Fasten your safety belts before you try that one.
Power is through a direct drive in-board mounted amidships, with a three-blade 13 x 13 prop. Standard power is a 185-hp Pleasure Craft in-board which is a 302 Ford block, but our test boat was equipped with the optional 215 hp. Interesting to note here that the engine is a left-hand rotation block; many of its parts are standard automotive; far less expensive than their marine counterparts. A nice bonus for Shamrock owners as the years wear on.
Starting where most boat trips start – at the slip – the Shamrock gives a great first impression. The wide, uncluttered gunwales make getting aboard easy; the non-skid decking is non-skid even when wet. Unlock the pilothouse door, slide it open. The gauges are all in clear view and switches well marked.
After casting off, you have plenty of time to haul in the bumpers and stow the lines; the keel prevents the boat from blowing sideways in the slip. Back out, and as she starts to swing, slip into forward and straighten out the wheel. There is none of the usual wheel spinning.
If she’s up to operating temperature as you hit the open water, punch the throttle hard. The bow will rise very gently, then drop down again as she planes off. There’s very little “hump” and the rate of acceleration is almost constant.
By this time you’re making your way out at about 30-35 mph. The Shamrock just blasts through waves sending sparkling spray off to the sides. Slide the pilothouse door closed and turn on the wiper; you’re dry, comfortable. and protected from the wind.
Change your heading just as the boat is going up one of those big rollers at an angle. She’ll track right up and over without a lurch and then as you turn the wheel, will answer the helm without rolling at all. The effect is uncanny. When you’re back in calm water, try running a really tight turn at full throttle. The boat always holds dead flat, with only the slightest slide at the transom. This is the keel at work again. As you enter the comer, the boat will want to bank to the inside, but the keel bites in, making her want to roll out instead. The two forces cancel and the boat stays flat.
Regardless of the weather and water conditions, the Shamrock will still make her way along with authority. One would expect the flat bottom to pound heavily but it doesn’t. It isn’t a Cigarette with 26° of dead rise, but you won’t have a black and blue behind either. The keel cushions the fall.
Bob Whitehouse of Durham Boat Sales, who offered the Shamrock for testing, was at dockside to welcome us back. His first question was, “How fast did she go on the radar?”, and he was disappointed with my 31-mph result.
We took the boat out again and after a few minutes at full throttle she was up to 33 mph and 4,100 rpm. I have no doubt that she’ll see 35 and maybe even 40 at full revs but the test boat had only 8 hours running and just wasn’t to let go yet.
We ran the test in Shamrock weather; that is to say, very rough with a strong easterly. That prevented me from running an accurate fuel mileage test which is a shame since the boat has quite a reputation for economy. The builder suggests 6 gal/hr at 2,800 rpm.
The Shamrock would suit a number of uses – even water skiing. It has so much clear deck space that deck chairs and a sunny day would be perfect for sight-seeing and canal cruising. The same attributes make her ideal for trolling and there are rod racks for six rods plus lots of room for down-riggers and outriggers. The clear transom is great too, and the flat floor and beautiful teak taffrail will be appreciated. Slow speed, continuous running is no problem for the inboard.
The optional teak swim platform is as nicely made as any I’ve seen with every piece shaped and smoothed. The two big under-floor wells have lift-up hatch covers and the forward well even has big sturdy handles and can be lifted out and used as a bin to bring your catch up on the pier. There is a small marine head in the pilot house and lots of dry storage there too.
The helm is generally used sitting, but if it’s really blowing, lift up the floor sections and stand down in the well. That makes a standing helm position with 6 ft 3 in. of headroom. The windshield pushes out on two braces too, for defrost and ventilation as needed with the doors closed.
I have one complaint; there are two unpadded edges in the pilothouse that are in a good position to cut your head. This is out of keeping with the rest of the boat.
With her mechanical specifications, quality design and construction and host of useful and desirable features, this is one boat that shouldn’t be subject to significant depreciation. The Shamrock is as good an investment as anything on the market.
Originally published in Canadian Yachting’s August 1979 issue.
Specifications:
Length – 20ft
Beam – 7ft 11in
Weight – 2,550 lbs
Fuel Capacity – 52 gallons
Engine – 302-cu-in Pleasure Craft (Ford block). 215hp; left hand rotation.
Photo Captions:
Photo 1 – Bow.
Photo 2 – The Shamrock’s long keel and good balance help it track level and punch through seas.
Photo 3 – Wide gunwales and open side decks make it easy to move around in this model.
Photo 4 – The interior can be kept dry with canvas that slip-on behind the pilothouse.
Photo 5 – The inboard is underneath the seats.
Photo 6 – The windshield swings out workboat style.
Photo 7 – A footwell allows stand up steering.