My Whitewater Boat is Complete Finally!

[Drowned Rat]

After a year of planning and working on this project, I'm finally ready for a trip. Here's the boat. It's 14' long 6.5' wide, 20 inch tubes for remarkable buoyancy.

The battery is a blue top Optima, 2000gph Rule integrated bilge pump, and a 12 gallon fuel tank that I anticipate will give me about 200 miles at full throttle. I'm hoping for close to 250 at cruising speed. That may be a bit optimistic though.

The motor is an 18hp four stroke with 2 minutes on it. I've got a long 10 hour break in period ahead of me, but the lakes are full and I'm taking it out for a shakedown cruise tomorrow.

I'm hoping for 25 mph, what do you all think??

 

[QC]

Re: My Whitewater Boat is Complete Finally!

Waaaaay cool DR. I just saw "Into the Wild", and to think you could now do his trip from Glen Canyon to the Sea of Cortes . . . backwards

I bet that thing's gonna throw a mean rooster tail . . . from the bilge pump

 

[tashasdaddy]

Re: My Whitewater Boat is Complete Finally!

i wanna go!!!!

 

[QC]

Re: My Whitewater Boat is Complete Finally!

i wanna go!!!!

Me too!!!!

 

[SpinnerBait_Nut]

Re: My Whitewater Boat is Complete Finally!

Me too!!!!

Heck ya DR, you need my big arse to hold that thing down.
Come get me.
Yehawwwwww

 

[DJ]

Re: My Whitewater Boat is Complete Finally!

Outstanding! Looks great.

What did you decide to do with the fuel/water seperator?

 

[BoogieMan]

Re: My Whitewater Boat is Complete Finally!

Dude I want one . The only thing wrong with it, it has a Tohatsu on it . You built that from the ground up, or is this a modification to a boat?

Just messing with ya. But I am a Evinrude man, I guess you can't knock em if you aint tried em.

Awesome job DR.

Hope the shake down test doesn't turn into a brake down test.

 

[Drowned Rat]

Re: My Whitewater Boat is Complete Finally!

Thanks guys!! I'm super excited. My trip is this June and I'll be sure to take lots of photos. This will be a play boat mostly and I don't know that I'll run all the rapids with it. The main support boat is a 37 foot pontoon that we're renting.

DJ, I installed studs in the transom and sealed them with 5200 so they won't have to be taken out. The filter is mounted to them with regular nuts because the wing nuts wouldn't fit. Not a big deal though, it still comes off easy. I attached the hose to the filter with quick disconnect fittings to speed things up further and to seal the filter as a unit when disconnected. Thanks for the help and tips!

BoogieMan, everything is custom but the hull. I built the frame, attached the deck fittings, modified the transom, etc... myself. I'm sure I'll encounter some problems my first run, but I don't anticipate anything major. Tohatsu probably wouldn't have been my first choice, but the price was right and they are good motors. This is my first Tohatsu so we'll see how it goes.

 

[scoutabout]

Re: My Whitewater Boat is Complete Finally!

Wow -- that thing is going to be a blast!

 

[Drowned Rat]

Whitewater Boat is Complete **Lake Test**

Whitewater Boat is Complete **Lake Test**

Well I made it to the lake finally to test the new rig.

A perfect day almost, a little windy. It threw some chop on the water which actually was okay because I wanted to see how the boat handled that too.

I had the boat fully loaded, about 750 pounds persons, motor, and gear. I was a little disapointed in the top speed (21.8 mph by GPS), although it had plenty of power and speed for this boat's primary purpose. This gives the boat a theoretical range of 175 miles at full throttle. Oddly, with the Smart Tabs in the water, I lost exactly 1 mph top end speed. I installed the retractor bracket on these tabs and it's interesting to deploy and retract the tabs under different operating conditions to see exactly what they are doing to the boat's performance. With the tabs in the water, the bow remained a little flatter for the hole shot, but not much. Using the tabs I could accelerate from a stop very slowly and the bow would stay flat. Without the tabs I had to jump on the throttle to keep the bow down before plane. With the tabs I could plane as low as 9.8 mph, and without 10.5 mph. The biggest advantage to the tabs on this boat was in high speed maneuvering. With the tabs I could make a full speed nearly hard over turn without ventilating the prop. It was really amazing how well the boat grabbed the water with the tabs. Without them I could come no where close to that performance. I either had to slow down to about half throttle or make the turn MUCH more shallow.

 

[januarysails]

Re: My Whitewater Boat is Complete Finally!

Whoa!!! I can't beleive it. YOU DID THAT. You must feel like a proud daddy. Congrats. I also can't get over the speed. I think we all of alot to learn from you. thanks for posting...

 

[azlakes]

Re: My Whitewater Boat is Complete Finally!

... looks great DR, would love to try your boat at Lee's Ferry. Was that test run at Bartlett Lake?

 

[Drowned Rat]

Re: My Whitewater Boat is Complete Finally!

Hi there, yes it was Bartlett. I can't wait to take it to Lee's ferry myself. There I'll really be able to put it through it's paces.

 

[azlakes]

Re: My Whitewater Boat is Complete Finally!

Hi there, yes it was Bartlett. I can't wait to take it to Lee's ferry myself. There I'll really be able to put it through it's paces.

... set a date was just there scouting it out last year. has an awesome campground(1st pic in the backround) with prestine launch. May is a great time of year i hear to go!

 

[Drowned Rat]

Re: My Whitewater Boat is Complete Finally!

Great pics. I'll go the first chance I get, but I'm not sure when that will be yet. May is good although it's still a bit chilly up there. Water temp is 47* year round. Have you been upstream from Lee's?

 

[azlakes]

Re: My Whitewater Boat is Complete Finally!

... yup but its been years so was itching to get back and see it. the thing i remember was gauging the release at Glen Canyon damn and how much the swell would rise, fall or flow the river. the fishing was awesome but heard thats changed a lot. its the thrill of the run now i hear is the rage... your boat would also be awesome on the run from Hoover damn to lake Mohave. That lake rocks. You built yourself a great boat to get to those hard to reach prehistoric looking places!

 

[BoogieMan]

Re: My Whitewater Boat is Complete Finally!

Are you pleased with the motor this far? I know you said your were "a little disappointed in the top speed". But overall how do you like that motor? How was the acceleration?

 

[Texasmark]

Re: My Whitewater Boat is Complete Finally!

Outstanding! Looks great.

What did you decide to do with the fuel/water seperator?

Looks to me like it's mounted up on the transom between the fuel tank and the enigne.

---------------------

Can't help you on guessing speed. Have no idea what the hull drag is on an inflatable.

Might toss in another prop if you are going white water running. Alum is surely the right material for hitting rocks.

You know they make rings that go around the prop that help to protect it from rocks. Don't know how durable they are, nor what they cost you in mph.

Looks like you did a real neat job of rigging it out.

So are you just going to ride and look; maybe camp out on the way?

Mark

 

[Texasmark]

Re: My Whitewater Boat is Complete Finally!

Guess I missed part of the post. Oh well.

Only thing I would take a second look at would be the seating. Take two people and pounding water and you have a pretty serious force acting on that alum tube that runs gunnel to gunnel; forces acting in 3 axes. A brace post in the center of the tube braced to the bottom may save you a potential serious problem.

Additionally, I'd take a second look at those blue straps holding the seats to the boat, and their clamp.

Mark

 

[Drowned Rat]

Re: My Whitewater Boat is Complete Finally!

AZlakes, yeah me too. It may be a bit chilly, but this is still Arizona! I'm going up there first chance I get.

Bman, I would like to have seen a little better top end, but I really shouldn't be surprised considering how heavily the boat was loaded. If I ran with 6 gallons of fuel instead of 12, took the battery off, removed the cooler and bow bag full of gear, it would be around where I wanted it to be at 25mph I'd bet. I'll have to try that next. Acceleration is good, average, for a 4 stroke. It's very quiet. I still have a lot of testing to do with it because I was just breaking it in the other day. I'm happy with the purchase. I'll probably be the only Tohatsu on the river as everyone else uses Honda. I guess I'm out of luck if I need to borrow parts.

Tmark, thanks for the reply and tips. I do carry and extra prop in the tool kit. When I take it down the river, I'll probably have 2 or 3 extra props and an extra lower unit among other things. The frame is made exactly for this purpose and comes from a company called NRS. The tube walls are about 3/16ths aluminum and they are VERY strong, and heavy unfortunately. There are actually 8 of those blue straps holding the frame down, 4 more going to the inside of the tubes that you can't see. It's quite sturdy. I carry extra straps, d-ring patches and glue on board as well as a substantial patch kit. It will take 10 days to get from Lee's Ferry (below lake Powell) to South Cove on lake Mead and we camp along the way. It's great fun!!