BOAT REVIEW McLay 741 Raptor

Tectrax has gone down the electric route. All amphibious systems rely on a power plant, separate to that which propels the vehicle in the water, to drive the wheels used for terrestrial operation. But whereas most of Tectrax’s rivals use a petrol engine to power hydraulics that raise, lower and turn the driving wheels, Tectrax has developed an all-electric system where the drive wheels and the hydraulic pumps used to raise and lower them are powered off a lithium iron phosphate battery.
Going electric offers several advantages, including savings in space and weight. Yes, the lithium iron battery, tricycle undercarriage, electric motors and associated equipment still add weight, but there’s no bulky (and heavy) petrol engine taking up valuable deck space inside the boat.

The Tectrax all-wheel-drive amphibious system has sealed, brushless electric hub motors inside each wheel. The wheel assemblies, or ‘legs’, are raised and lowered hydraulically, but compared to other amphibious systems, Tectrax’s are compact, sleek and well-integrated, with no visible hoses or wires.
Aluminium trailer boat manufacturer McLay Boats was quick to adopt the Tectrax amphibious system, creating the 741 Raptor which drew so much attention at last year’s Hutchwilco NZ Boat Show. Based on the popular McLay 701 model, the 741 Raptor addresses one of the challenges faced by all amphibious models: what to do with the wheels when they are not driving the boat.
All amphibious vessels are designed to raise their wheels clear of the water when the boat is running, but in most applications the wheels are exposed in the up position, which not only impacts on the boat’s aesthetics, but the wheel assemblies can also kick up spray.
With the 741 Raptor, Steve McLay and his team have gone to considerable effort to accommodate the wheels inside the boat, which really sets it apart from the others. Once they’re retracted, you’d never know you were looking at an amphibious vessel.
The 741 Raptor might be based on the McLay 701, but, says Steve, only the hardtop is identical – the rest of the boat is essentially new from the ground up. To accommodate the wheels, the engineers at McLay Boats came up with an ingenious sliding ‘bomb bay’ door in the bow and rear hull extensions which completely encompass the rear wheels when retracted.
With the wheels up, the 741 Raptor looks like any other McLay boat and there’s no risk of snagging fishing lines or tow ropes for water toys on the wheels.

Getting the bow door right involved quite a bit of development, explained Steve. It was a joint effort between McLay, Tectrax and an engineer they hired. The door section has an important hydrodynamic function when the boat’s underway, deflecting water and providing lift. As such, the door had to be as strong as the rest of the hull, which is fabricated from 6mm aluminium plate. It had to lock securely when closed, without rattling or banging as the bow cuts through the water. McLay has achieved a snug, almost seamless fit using a clever arrangement of welded lugs to hold the closed door firmly in place.

Supporting a boat on three wheels near its corners places the hull under considerable strain, but no extra internal bracing was required for the 741, said Steve, since McLay boats are already stiff laterally and longitudinally. However, the wheel assemblies add weight to the boat’s ends, so McLay added extra buoyancy at the transom and moved the fuel tank and batteries around to ensure optimum trim.
Full of fuel, the boat weighs around 2,400kg on the water. The Tectrax T3000R AWED system is rated for up to 3,000kg, so the Raptor easily falls inside its safe operational limit even with six adults onboard. On its custom-built drive-on trailer, the rig comes in at 3,400kg, just inside the maximum tow rating for Steve’s Jeep Grand Cherokee.
The Raptor’s transition from land to water and vice versa is very like other amphibious vessels I’ve experienced, except it’s noticeably quieter. The electric motors powering hydraulic pumps that raise and lower the tricycle undercarriage emit little more than a hum and the brushless electric hub motors are also very quiet.

We drove the 741 Raptor in and out of the water several times at a steep, rocky beach on the shores of Lake Wanaka. The Tectrax system drives all the wheels (some amphibious systems only drive the rear wheels) and should a wheel lose traction, traction control directs torque to those wheels with grip. It seems a pretty robust system capable of handling steep and uneven terrain. The Tectrax graphic interface shows the Raptor’s roll angle, warning the user well before there is any risk of the vessel tilting dangerously.
On the water with the wheels retracted, the Raptor is like any other similar-sized outboard-powered boat. It benefits from digital throttle and shift, while Zipwake automatic trim tabs do a good job of controlling pitch and roll. Power is supplied by a V6 Mercury 225hp outboard, which provides ample performance, but Steve is considering upgrading to a V8 250hp Mercury to boost the cruising speed. As reviewed, the boat cruises comfortably at 26 knots with a top speed of 34 knots.
Underway, the Raptor handles much like any other similar-sized McLay hardtop. One of the beauties of the Tectrax system is that it doesn’t encroach on cockpit space, so in most respects the 741 Raptor offers all the family-friendly features of the popular 701, including storage and seating options. The only trade-off is as a result of the retracting the front wheel into the hull, which reduces the usable space in the forward cabin and restricts access to the forward hatch. But McLay still manages to include a pair of child-sized bunks either side of the wheel housing.

This Tectrax systems adds 580kg to the boat’s gross weight, resulting in a slight performance penalty, but by selecting the right propeller, Steve still enjoys brisk acceleration and good throttle response. In fact, says Steve, the extra weight benefits the boat’s ride, especially in rough conditions, and contributes to its excellent stability at rest.
Except for the joystick control on the dash and the Tectrax graphic interface displayed on the Simrad 12-inch NSS Evo MFD, most of the time you wouldn’t know you are riding in an amphibious vessel. The 72-volt battery and charging socket are hidden away in a transom locker, alongside the McLay’s conventional 12V house and starting batteries, and the U-Dek lined cockpit is unencumbered by an engine box.

The Tectrax battery is housed in a stainless-steel case. It’s quite compact, weighs just 48kg, and is good for at least 35 minutes continuous run time allowing for some uphill and soft sand use. In Steve’s personal experience it averages around 10 entries-and-exits between charges. Plug-in charging using a domestic socket and the supplied fast charger takes less than two hours for a full charge.
Operating the Raptor on land is straight forward too. The large joystick/lever on the left-hand side of the console is used to select forward or reverse and to adjust the speed: push it/pull it to increase the speed in either direction. Maximum speed on land is 8kph and the brakes come on automatically when the throttle is released.
Pressing a pair of buttons on top of the control lever turns the front wheel to the left or the right, a one-handed operation, with the wheel angle indicated on the Tectrax graphic display. With the front wheel on full lock, the turning circle is actually pretty good and forward vision from the helm isn’t too bad either. A bow camera is useful for covering the blind spot directly below the bow and provides visual confirmation of the front wheel’s position, as does peering through the window in the front wheel Entering the water is always undertaken bow first, the wheels maintaining forward momentum until the boat is floating and the partially tilted outboard motor can take over. The outboard can usually be started while the rear wheels are still in contact with the beach.

With the outboard providing thrust, the power to the wheels can be cut and the wheels raised. Rocker switches on the dash, one for the front wheel assembly and the other operating both rear wheels together, raise and lower them. Once the wheels are all the way up and the bow door is closed, the Raptor is ready to go – water inside the bow wheel compartment drains away as soon as the boat gets underway.

Leaving the water reverses the procedure: as you approach the beach under engine power with the outboard partially tilted, lower the wheels until locked and apply electric power while still floating. As soon as all three wheels are in contact with the bottom, kill the outboard and drive up the beach. Once high and dry, the Raptor can be made to ‘kneel’ by retracting the wheels until it rests on its keel. Kneeling makes embarking and disembarking much easier and takes the strain off the undercarriage. It is recommended when storing your Raptor.McLay’s 741 Raptor looks and behaves like any other typical robust, practical and roomy McLay hardtop cruiser, but the addition of a thoroughly integrated Tectrax amphibious system sets it apart from the rest of the McLay range.
Amphibious capability makes the Raptor an attractive option for owners with beachfront properties or beach-only access to the water. An optional road trailer adds versatility, allowing the Raptor to be transported anywhere another trailer boat can go, but with the ability to launch and retrieve itself off the beach where no boat ramps are available.
This Raptor is Steve McLay’s personal boat, but the company has already taken orders for more and expects to build around six Tectrax-equipped Raptors a year.