19 foot Baja Sport I/O powered by an Allison 250-C18  
 

 

To learn more about the Allison 250 C-18 Turboshaft engine, click here

 

Here is the boat we plan on using for the project. It is a 19 foot, 1989 Baja 190 Sport. Original power was a Mercury Marine 190 horsepower V6 turning an Alpha One I/O drive. We bought the boat used for around $4,000 from a marina out on Long Island. We feel this boat is a perfect candidate for our turbine project, and it was in pretty good shape.

 

Here is a picture of the Alpha One drive, removed from the boat. The drive is in good condition, and features a 1.84:1 gear reduction. This will reduce the input speed of around 6,000 rpm, to a propeller speed of approximately 3300 rpm. The prop on the drive in the picture is way too small; a much beefier unit will be necessary to absorb the 317 horsepower of the turbine engine.

 

The above pictures are the components for the 250-C18 outdrive brake kit. These parts are produced by Mark Nye of Nye Thermodynamics. The splined shaft in the top right picture plugs into the female output section of the engine. The shaft features a sealed bearing, already press-fit onto the shaft. The shaft is supported in the aluminum bearing carrier, shown in the bottom left picture, and the brake caliper bracket bolts in place over the works, to retain the bearing and shaft. Finally, the brake rotor bolts onto the output shaft flange. We supply the brake caliper and pads.

 

The above pictures show the outdrive brake kit mounted to the Allison engine. The picture on the left is without the brake caliper, while the picture on the right shows the brake caliper, from a typical Yamaha motorcycle. This brake assembly will be used to stop the output shaft from turning so that the transmission can be shifted. The output shaft of the unloaded engine spins too quickly, even at idle speed, for smooth and safe shifting to take place. The drive brake is used to momentarily stop the output shaft so that shifting can take place.

 

The above pictures show the bilge and engine compartment. The picture on the left is of the completely stripped out hull. We had to build out the stringers running through the bilge to accept the 250-C18 engine mount. The picture on the right shows the actual engine mount in place. We used the frame that came in the shipping container for an engine mount, after some modifications to make it stronger.

 

Shown above is the driveshaft. This is the coupling between the engine and the outdrive. We had to have this part custom made, due to its short length. It had to be short because the short engine compartment means that the engine must be mounted very close to the transom.

 

The above pictures show the Allison 250-C18 engine installed in the hull. It's a perfect fit! Notice the slick alignment tool Eric devised to line up the engine output shaft with the drive unit. The proper alignment of the engine and drive is essential for long life of the components.

 

This is the captain's chair. Bolted to the side of the seat mount is the output shaft brake lever, along with hydraulic master cylinder and fluid reservoir. Very slick indeed...

 

This is the dashboard, still in the works. Turbine instrumentation includes the three in one oil temp, oil pressure, and fuel pressure gauge, indicators for N1 and N2 rpm, and the all important exhaust gas temperature gauge.

 

Here is a cardboard mockup of the port fuel tank. We are going to use two 25 gallon aluminum saddle tanks, in the rear of the boat, on either side of the engine. Because of the light weight of the engine, the fuel tanks should be placed as far back as possible, to restore some of the boat's natural weight distribution. Too much weight in the front of the boat as compared to the rear, and the bow might not come up enough when the boat is on plane. A total of 50 gallons should be enough for two good hours of running, as the turbine engine burns around 22 gallons an hour at cruise setting.

 

The picture above shows the inside rear of the boat, on the port side. Most prominent is the oil tank for the Allison turbine engine. Oil is drawn from this tank and circulated through the engine main bearings and the accessory gearbox before passing through an oil to water heat exchanger, which uses sea water drawn up by the outdrive water pump as the cooling medium. The oil then returns to the tank. Supported by the tank mounting bracket are some of the key electrical components, including the starter solenoid, generator field solenoid, voltage regulator, and reverse current relay.

 

Here is another view of the oil tank, from the top. This view affords a better look at some of the electrical goodies. To the left of the tank in the picture is one of the battery trays. This tray will hold one 12 volt battery. The other battery will be on the opposite side. The two batteries are wired in 24 volts, to provide energy for starting. A gas turbine, once running, requires no electricity to run, so, in theory, one could disconnect the battery after the engine has completed the start cycle, and the engine would still run.

She's Alive!!!...Check out the new video in the multimedia section to see our first test firing of the engine, as well as our first test of the outdrive unit, despite some miserable, rainy weather. Special thanks to Marty the outdrive expert from Moss Marine in Long Island for getting the outdrive running smoothly. Click here for video.

 

The above pictures show the fuel tanks that we had fabricated for our turbine boat. Each tank holds 23 gallons, which should give us our target of two hours of good, hard running when completely filled to the 46 gallon total capacity.

Initial test runs in the boat show that everything is working really well. The hull is very stable, even in rough water, and the engine and the drive are working without a hitch. As can be expected, there are a few kinks to be ironed out before the boat is complete. The biggest problem we are facing right now is heat. The heat from the engine appears to be recirculating through the cockpit at speed, and this makes the cockpit very hot. We are looking into adding some large, elbowed exhaust pipes, to carry the exhaust clear out of the boat over the transom. Our search continues. We plan on doing another test run in the very near future.

Today (9/22/02), Eric and I carried out an extensive test session for the turbine boat. We tried a number of modifications to intake ducting, exhaust ducting, and controlling airflow into the boat and around the engine, to reduce the temperatures inside the cockpit, and also to keep the turbine outlet temperature down to normal levels. Removing the windshield has helped to keep us cool at speed. We also experimented with a number of different props, in order to find the one that will bring N2 rpm up to 100% so that we are not overtorquing and overtemping the engine to get full power and maximum performance. Overall, it was a very successful day, and the boat is getting closer and closer to being fully dialed in. We are also very impressed with the way the Baja hull handles the rough water. We will shoot some video footage of our next test session, and post some clips up on the website.

The above pictures are of our turbine boat in action. These pictures were taken on Sunday, September 29th, 2002, out on Long Island. The boat is pretty much completed now except for the finishing touches, such as the minor details and all the cosmetic touches. We plan on removing the existing bottom paint from the boat, and replacing it with a gel coat finish all around. Removing the bottom paint should reduce resistance and increase top speed. We've already seen speeds at least a little higher than 55 mph, and that's with the N2 governor turned way down and our prop selection still not perfect. We expect to reach 70 mph fairly easily, and hope to venture into 80 mph territory when everything is optimal. We also have to decide whether we should replace the back seat, or just leave it out, and we have to fabricate some kind of engine cover.

The boat is an absolute blast to drive. The torque of the turbine under acceleration is phenomenal, and lifts the bow high up out of the water. The boat comes on plane quickly and accelerates up to speed in a matter of seconds from the hole shot. Engine response is very rapid, as long as N1 is above 75% to 80%. From idle, the engine takes a few seconds to respond at all to the throttle pedal, but when it does, watch out! The trick is to figure out when you are going to need to add power in advance, and also to keep N1 up as much as possible. Overall, the boat has exceeded our expectations, and we're all very pleased. I'd like to give Eric a big thank you for helping me get together such a neat boat. Thanks Big E!

We shot some great video during our little test session this weekend, and Eric even took out his turbine boat, so we could zip around the bay and astonish the onlookers even more. There are three movies in the videos section. Be sure to check them out!!! Also, special thanks to Wes the helicopter pilot for shooting video, Bart for lending us his cleaver prop, and Marty the outdrive guy for getting the drive running so well.

 

The above pictures show the nearly completed boat on the trailer and at the dock, right before we took it for a spin this past weekend. The boat is running really well and we had a great day on a calm but chilly October day. We rigged an N2 governor adjustment lever in the cockpit, so we were able to taste all or at least most of the Allison's 317 horses. The added power when the governer setting is increased is immediately apparent. Increasing the power has made it clear that we may still might not have enough prop on the boat, so the search for the ideal propeller continues. We also need to fabricate and install the permanent exhaust stacks and a few other small items. With the weather getting cold, we may only have one or two more opportunities to run the boat this season.

 

The above pictures provide a rundown of the cockpit layout of my turbine boat.

1st image (left to right)- This is an overall shot of the dashboard. In the center is the steering wheel with the Baja symbol on it. The primary instruments are on this main panel. The gauge in the absolute center right above the steering wheel hub is the TOT, or turbine outlet temperature gauge. This is the most important gauge for monitoring engine power, and the gauge I watch most carefully when running. Maximum continuous temperature is 690 degrees C, but the engine is allowed to peak for short periods of time under acceleration, and when calling on the takeoff power settings.

2nd image- This shows the 3 in 1 gauge. It displays engine oil temp, engine oil pressure, and fuel boost pressure.

3rd image- This is the speedo. It goes up to 55 mph. That's not high enough. To the left is the fuel level gauge, and below that is the drive trim indicator. (not shown)

4th image- These two gauges are the tachometers for N1 (gas generator), and N2 (power turbine). They display engine rpm as a percentage of the maximum value.

5th image- This is an alternate panel on the center console of the boat. From left to right, is the boat hour meter, a combination voltmeter and ammeter, and the engine torque pressure gauge, which shows the engine torque at the output gearbox, as indicated by oil pressure. Further to the right is the depthfinder, and below it is the N2 governor adjustment handle.

6th image- This image shows the primary engine control switches. The key switch actuates the starter and the igniter plug when ignition is enabled. The switches are to enable the ignitor, to activate the fuel boost pump, and to switch the starter generator into generator mode.

7th image- These are the panel control switches. There is a switch for the horn, for the exterior lights, a fuel tank gauge selector, main panel power, and bilge pump.

SMALL UPDATE (11/10/02)- Today Eric and I took advantage of indian summer to take the turbine boat out for one last time before we wrap it up for the winter. We are in the process of finishing the stainless steel exhaust elbows for the turbine, and I will post some pictures of them soon. We also completed the intake housing box, which seals off the engine intake from the engine bay, and allows the engine to draw air from the blower vents mounted on the side of the boat.

Overall, the boat is running really well, and by the time next season rolls around, we will have all the finish and trim done, and the boat will be ready to come to my marina in Brooklyn, NY, where it will reside permanently.

2/11/03- Despite the nasty winter we've been having, it is time to start thinking about getting the turbine boat back into the water. I'd like to have the boat fully finished by the time we launch it. For now, the boat is still under wraps, but arrangements are being made.

Eric has been working on the finish for the exhaust outlets that will carry the hot exhaust out over the stern of the boat.

Still too cold for boating!

Aside from installing the exhausts, we need to work on the interior and exterior finish of the boat, install some type of engine cover, wind deflectors, and a few other items. Stay tuned for more updates as the weather warms up!

Spring 2003---

The turbine boat is currently having fiberglass and trim work done. I intend to keep the basic white with black stripe color scheme, although I would like to add some accents to spice it up and basically make the boat look like new. I have left this work up to Dennis Vogel. Dennis has years of experience in fiberglass boat work, and is a true professional. If you are in the Long Island area and need boat work done, send him an email: vog1@aol.com

The pictures below show the turbine boat just out of winter storage and being worked on by Dennis. He has already removed the bottom paint, and will refinish the underside of the boat with a smooth gel coat finish.

The seats are being worked on at a local upholstery shop. Dennis will also refinish the dash, add a custom engine cover, and add small windshields to keep the wind out of our eyes but still allow some cooling airflow back to the engine. Stay tuned for more progress...

6/1/2003- I went to check out Dennis Vogel's progress today. Dennis has completed the refinishing of the boat exterior, as well as fixing up any scratches, gouges, and gashes in the finish. All that is left on the exterior is a final polishing to shine the boat up nicely. In the top three images, you can see the plexiglass windscreens that Dennis has added to the boat. These windscreens were actually made from the canopy of a Grumman F-14 Tomcat fighter jet, which I think is very appropriate.

The bottom three pictures show a mockup for the engine cover. The engine cover will have two cutouts in the top to let the exhaust protrude. It will be hinged at the rear, and will rest on a crossbrace spanning the gunwales. I think I will leave the front of the engine cover open, to allow the burner to poke out, as shown in the bottom right picture. This will allow for cooling air to make its way under the engine cover. I will have two holes cut in the transom to ventilate the engine compartment. I will have the option of installing two rear seats directly in front of the engine cover on either side of the burner. While I don't really intend to carry a lot of passengers on the boat, the rear seats might help to improve the appearance of the boat. I've yet to decide.

As a side note, check out the hot boat in the background of the top right picture. It is a 40 foot Skater catamaran with some big horsepower and two Mercury Speedmaster drives. A pity though, no turbines...

7/2/2003- Last monday night, the completed turbokart.com turbine boat arrived at the marina where it will be moored. Under cover of darkness, we backed the trailer into the boatyard. We will be launching the boat this following monday. Following that will be tons of pictures and videos showing the finished boat in operation, as well as describing the construction of the boat and the systems. We can't wait to run it.

 

August, 2003- The boat is now totally complete and it runs like a dream. I have a couple of different props I am using on the boat, depending on the conditions, and whether I am going for top speed or more powerful acceleration and more stable handling. So far I have reached the highest speeds with a chopper style prop, although the engine still has a little more power in store that the prop is not using. With the right prop, a light fuel load, and the right conditions, there is no doubt that the boat is good for 70 mph. I acheived 64.5 mph as indicated on the GPS as my record so far.

Break out the champagne...As you can see from the pictures I have christened the boat with a name, thus making the project complete.

I shall call it...Fine Whine.

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Now that the boat is complete, there are some possible projects on the horizon. I have always wanted to build a large go-fast boat, perhaps a catamaran, with a couple of big horsepower turbines. In time, this dream may materialize. In the meantime, I have given some serious thought to performing a little upgrade to Fine Whine.

I eventually plan on swapping out the T63-A-700 (250-C18) engine for a T63-A-720 (250-C20). The 720 is essentially identical to the current turbine except that the C20 has a takeoff rating of 420 horsepower which should really make the boat fly! Since the engines are essentially the same, the swap should be a piece of cake. The only major change I will have to make is to change the outdrive to a Bravo 1 drive, which will be much more capable of handling the torque of the turbine.

I am also working on putting together an action packed video of the boat blasting around the bay near where I live. I will post this video and clips on the website as soon as it is complete. Stay tuned!

Keep checking back for more updates!

10/10/05- Final Update---The turbine boat has been sold to a lucky owner. I hope he gets as much enjoyment out of it as I did.

 

 
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