ALUMA-JET- Duracraft 1648 SV Jetboat Conversion

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PSG-1

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Here's some photos of my project that I did back in 2005:


It began as a 1997 DuraCraft 1648 SV that someone painted with copper paint and left in saltwater. I bought it for 50 dollars Corrosion Damaged Hull.jpg

Corrosion Hole Size.jpg


As you can see, this hull was severely pitted and corroded. However, the only place the corrosion went entirely through was basically along the center V of the hull. Everywhere else was just pitting.

So, I repaired the damage along the center V like so:

Corrosion Repair.jpg





First modification-hatches for fuel tanks Fuel Compartment Hatches Closed.jpg

Fuel Compartment Hatches Open.jpg




For my next modification, I wanted a false bottom, with a layer of floatation foam between each set of ribs, along the sides, as well as the bottom. So, I made a false bottom out of 1/16" diamondplate, with the sides being 1/16" smooth aluminum.
Inner Hull Body.jpg

Foam:

Inner Hull Flotation.jpg

False bottom installed: Inner Hull 2.jpg

False bottom, looking toward stern.Inner Hull.jpg Notice there is a gap between the rear bench seat and the back edge of the false bottom. This is where I have to extend the rear bench seat for the length of the engine. That's next..............
 
OK, next step...extend the rear seat area:

I used some 16 ga aluminum sheet, along with some internal bracing, to make these extensions:
Battery Compartment and Jump Seat.jpg

One on each side:Engine Cowl Removed.jpg


Next, I made the engine cowling, using some 1/8" aluminum plate. I used that thickness, because I wanted it to be strong enough to walk on it:Engine Cowl Installed.jpg

With all that done, it was time to build the console. I fabricated this from 1/8" aluminum plate, as well, because I wanted it to be stout.Center Console.jpg Console Front.jpg Console Switches.jpg


Next, I decided that all wiring and cables should be routed above deck to the console, to simplify replacement or repair, but I needed a cover for the area where the wiring and cables crossed the floor, even though I planned to put it all inside of non-metallic watertight electrical conduit. So, this is what I ended up doing: Wiring Harness Cover Plate.jpg
Wiring Conduit.jpg

With all the cosmetic work done on the interior, it was time to get busy installing the jet unit and the engine. That's next........
 
Mechanical time......this is where it gets tricky:

1998 Yamaha XL1200W pump

Jet Drive Assembly.jpg


The point of no return.....getting ready to cut out the hull tunnelEngine Compartment Insulation.jpg

Jet Pump CutOut.jpg

Jet Drive Cut-Out.jpg

Notice the 1/4" plate now in place over the hull. The 2 will be tied together, to make the hull more rigid, and the plate will give me a place to mount my engine. Engine mount rails will fit in the slots along the sides of the 1/4 plate:


Jet Drive Cut-Out 2.jpg


At this point, I now have to tie the hull together with the 1/4" plate:
Jet Pump Cutout- Floor Cross Section.jpg

But keep in mind that the XL120 pump has a taper to its shape (of course it does, why would they make this easy?!) so, that shape had to be built in to the hull with a lot of welding, grinding, and cussing! Enough cussing to make a drill instructor blush. A real PITA, and I do NOT mean a type of bread!!

Jet Pump Cut-Out Reinforcement.jpg


OK, now I had to build a tunnel box for the pump to bolt into:

Jet Pump Housing 2.jpg

Also had to have a 'horseshoe' shape to fit the intake scoop of the pump:Jet Pump Transom Box.jpg

Jet Pump Housing Completed.jpg That orange line you see is the waterline of the boat, tested with the amount of weight, distributed as it will be in the boat when completed. To find the waterline of any boat, simply dump some orange powdered chalk in the water and it will cling as a scum line to the hull, giving an approximate water line.

With this done, I bolted the pump in place, and made the mistake of using 5200 instead of RTV ultra black. NEVER, and I do mean NEVER, use 5200 on anything you don't intend to be permanent! I found this out the hard way then I had to replace this pump scoop after I burned out the thru-hull bearing by having the engine mis-aligned. Needless to say, it came out in pieces, and it was a PITA to get those loose. 5200 is some tenacious stuff! But I digress.

Pump bolted in:Jet Pump Inside View.jpg Jet Pump Installed.jpg

The next step was to install the engine...........
 
With the jet unit taken care of, it was time to get on the engine.....

Got a 1995 TS900 for 600 dollars, and it was a running ski! First step, pull the engine. Engine-Tigershark 900.jpg

Doing some initial measurementsEngine Mounts.jpg

I wanted to have a rail design, while keeping the mounts as low as possible. So, the best way was to notch the tubing and inset the mount plates

Engine Well Reinforcement.jpg

Engine Mount Plate Mockup.jpg

Engine Mounting Rail-Carriage Bolts.jpg mounts secured with carriage bolts



After notching the 2x 1/4" square tube, I used some 3/8" x 3" flat plate for the inset:


Engine Mount.jpg

Engine Mounts Installed.jpg

Engine Plate 2.jpg

With the engine and pump now installed, I had to fabricate the fuel tanks, then start hooking up wiring, hoses, and cables.
 
For the fuel tanks, I used a factory made tank, but it had to be modified, because of the angle of the gunwale.
Fuel Tank Modified.jpg

Fuel Tank Fit-Up.jpg I found out later that putting foam around a fuel tank is a bad idea, especially in salt water, as it sets up perfect conditions for crevice corrosion. The foam has since been removed, and the tanks now sit on risers made out of square aluminum tube, with rubber dampeners.


Anyhow, with all this done, I had to get to work on my controls.

For the steering, I used the heavier Teleflex CC694 series cable (I think they've changed the number to a '640' prefix now.) It's a stainless push-pull cable, with a 4" travel, and a 5/16"x24TPI end. I also used a teleflex jetboat steering helm, with the 270 degree turn radius. They also have a 135 degree, but I figured that would be a little too sharp, I wanted a little more room for error, I didn't want the steering to be over-responsive to movements of the wheel. So, that's why I used a 270 helm.

For the reverse gate, I initially used the flimsier CC633 series cable (that has 10-32 ends, instead of 5/16) but found that it would get bent under the thrust of reverse, and after replacing it three times, I went to the 694 series cable for reverse as well.

For the throttle cable, I bought some throttle cable conduit from a source online, and then I bought some 1/16" stainless cable from McMaster-Carr. For the throttle body and control handle ball ends, I used some 1/4" brass round stock, with a 1/16" hole cross drilled for the cable, and then on each end, I drilled and tapped for a #6 setscrew.

But I needed a control box. After looking around online and not finding what I wanted, I built my own. It's basic, it's simple, but it works....Control Box.jpg

The outer lever is for the reverse gate. The inner lever is for the throttle. Both levers have enough travel to accommodate the cable assemblies for full travel.
Control Box (top view).jpg



Then I had to fabricate a new wiring harness 20 feet long, to run from the console back to the engine.

Wiring Harness.jpg


Then I had to install the engineEngine Completed.jpg

Upon completing that, I was ready for my test run!
 
Needless to say, I was very happy to see my hard work pay off:Coming Up!.JPGBack On Plane.JPG

And even more happy to be a part of something bigger, with my boat making its debut, as well.....Larry The Cable Guy.jpg From the History Channel show "Only In America" with Larry The Cable Guy, Episode-"Larry In Hillbilly Country" filmed Nov. 22, 2010 on location in South Carolina.

(Yeah, the guy wearing the green T-shirt in the mud with Larry was yours truly)
Dan and Dan.jpg

Got Er Did!.jpg


I've always thought my jetboat was cool, but I NEVER thought I would see it on national TV! When they showed it going through those oyster flats, I can't tell you the sense of pride that I felt. They had numerous other shots of the boat throughout that episode.

And yeah, it was pretty funny watching the camera crew and Larry scrambling around in pluff mud (if you aren't used to walking in the stuff, you can get stuck really bad, as seen on that episode)
 
Like what you see so far? Want to see more? How about a series like "American Chopper" except, geared towards jetboat building?

Check out my youtube channel, there are a lot of videos of the Aluma Jet, both in it original version from 2005, and now in its new High Output 4 stroke configuration, just this past year.

I also have 2 "seasons" of my series I call "American Jetboat" Season 1 is the original build, back in 2005. There are 3 10 minute episodes of season 1.

Season 2 is called "High Output" and that was done this past summer. The old Tigershark engine died a horrible death after some POS with no CFC (common friggin' courtesy) in a para-sailing boat swamped me with a 3 foot wake, and blew the engine up, so, it was replaced with a Yamaha MR-1 High Output engine. There are 6 10 minute episodes of season 2.


Check it out at:

https://www.youtube.com/user/HKPSG1Shooter?feature=mhee
 
Wow that is pretty amazing! What a boat find as well and you did one the best builds ive ever seen! I sure would like to build one of these jet jons but they sure seem like alot of work if youve never done it before!

More pictures of any other builds would be great! Also where did you get you switches?

Thanks and great job!
 
Yeah, they are a lot of work. You pretty much have to have your own welding and machining equipment, and the know-how to fabricate and design.

If you had to pay for a welder and a machinist to do all of this, you'd go broke real quick!


As far as my switches, they are regular toggle switches I picked up at west marine, they are the type with the illuminated tip. The switch is wired to the ignition circuit, so when the boat is running, all switches glow white, unless turned on, then they glow red. Looks pretty cool at night. Also, I replaced all of the bulbs in my gages with LED's, to minimize power usage at night.

The labels you see mounted around the switches, I fabricated, by cutting thin strips of aluminum, and then using a letter stamping set, then securing them with 1/8" rivets. The switch labels and the control handles have since been changed out for bronze counterparts, to dress it up a little.
 
Looks like a good fuctional build. I certainly is a good feeling to see your hard work earn some recognition. Your boat is about the same size as mine now. How much better is the high output engine vs. the old tigershark? I guess if my Seadoo engine ever dies I'll look at getting a water cooled street bike engine and mounting it in the hull.

Jamie
 
Ranchero50 said:
Looks like a good fuctional build. I certainly is a good feeling to see your hard work earn some recognition. Your boat is about the same size as mine now. How much better is the high output engine vs. the old tigershark? I guess if my Seadoo engine ever dies I'll look at getting a water cooled street bike engine and mounting it in the hull.

Jamie



Yeah, like I said, I've really enjoyed this boat, I've had more fun with it than with any boat I've ever owned, including the Sea Doo Speedster jetboat.....at idle, it had about 2 feet of draft, it could never go into the areas that the aluma-jet will travel. And then to see it on the History Channel was just awesome, knowing that it was a boat that I built from scrap into what it is.

My hull is 16' 4"...and then I have the platform on the transom, so, total length is probably about 17' 6" or so.

As far as how much better is the High Output than the Tigershark, I can't even begin to describe it! If you check out my youtube channel, there's a video showing the sound levels of the 2 stroke and the 4 stroke engines in this boat. And then I have a video showing the hole-shot, where I blast a 18 ft Sea hunt outfitted with a 150 Mercury Optimax. Granted, the Sea Hunt has the top end, but out of the hole, the High Output rockets past the Sea Hunt. Top end of my boat is about 10 MPH faster than the Tigershark, and I think I could probably get that higher if I experimented with impeller pitch. Right now, I'm running a 13/19 Concord swirl impeller, which gives me a lot of hole shot, but I think may be limiting my top end somewhat.

The difference between the 2 and 4 stroke is very noticeable. Ya know how when you rev up your 2 stroke jet ski engine out of the water, how it winds up to a high RPM, then slowly winds back down, with the familiar pop-pop-pop as it winds down? None of that with the 4 stroke. The second you bump the throttle, it responds, there's no lag to it. And the RPM winds back down instantly, there's none of that lag like with a 2 stroke.

There's no smoke, either, as it's a 4 stroke. So, no gagging on fumes while idling with the wind on your stern.

It's also much quieter, being a 4 stroke. Also, if you check out "American Jetboat High Output Part 3" you see that we have taken out the original jet unit tunnel, and made it 4 inches wider, which gives room for the exhaust to run into the tunnel. On the Tigershark, we had the exhaust running out the back of the boat. Yamaha routes the exhaust through the tunnel, as we did, and that also helps to quiet down the sound signature. The platform on the transom also helps to muffle the noise.

And it seems to be better on fuel consumption...roughly 3 gallons per hour, or 5 MPG, is what I'm getting with the HO engine, with 2 people on board.

The High Output is also equipped to carry weight better. The Tigershark was a 2 person jet ski, the HO engine came out of an AR-230 jetboat. These boats have 2 engines, and the boat weighs 3000 pounds empty, then its capacity is another 1800 lbs, for a total of 4900. Divide that by 2, because there's 2 engines, and you come up with 2450 lbs max load for each engine. My boat might weigh 1000 lbs, so, that gives me another 1450 lbs before it's totally maxed out on weight.


As far as a water cooled street bike engine.....that's what the MR-1 High Output is. It is the marine version of their R-1 motorcycle engine. These engines are actually designed to run at 14K RPM sustained. The HO engine runs at 10K RPM, so, it's not even maxed out. It also uses a 1.47:1 reduction gear which steps the impeller's top speed down from 10K to about 7,400 RPM, as the average jet pump can't sustain that kind of RPM without damage to bearings or thru-hull seals. not to mention once they reach a certain RPM, they will actually begin to lose efficiency.

If I do another jetboat build, I'm probably going to use a Sea Doo 4tec intercooled supercharged 215 HP engine. With the closed loop cooling system, you never have to worry about sand or mud clogging it and running it hot, nor do you have to flush it every day you use it in salt water, you could leave it tied up at the dock a couple of days, with no ill effects (as long as you have galvanic protection of your hull and jet unit with a lot of zinc anodes)

And just a side note FYI, a 16 foot johnboat needs about 36 sq inches of zinc for proper galvanic protection in saltwater. In freshwater, instead of zinc, you use magnesium anodes for protection. Because the bottom of my boat had some pitting, one of the first things I had to do was to sandblast the entire bottom with a 60/90 grit of 'Starolite' blasting media, to remove every trace of that copper paint. Then, the entire bottom was painted with a 2-part polyamide epoxy (submarine paint) to seal the pitting. Then a coat of Copper Thiocyanate paint every year, for antifouling. (Copper Thiocyanate for aluminum boats, Cuprous oxide for fiberglass.....NEVER use cuprous oxide on aluminum, it will destroy the boat!!)

But, six years later, a lot of that paint is wearing out, so, I plan on having the bottom sprayed with Line-X truck bed liner. The guy told me that it can actually be applied with a surface as smooth as paint, the texture you see in truck beds is created by standing back from the surface to spray the coating. I know a few people that have had their hulls done like this, and I'm probably going to do the same in the next few months. This would give the hull some long-lasting protection.

At any rate, I enjoyed the thread on your boat build, as well. Reminded me of the long process I went through to do mine. Lots of long days and long nights, and a lot of trial and error, and going back to the drawing board. Heck, my girlfriend was about ready to file a missing persons report on me, I was spending so much time in the shop....LOL

And it seems like every time I say "it's done"....I find yet something else to improve or change. Seems to be a never ending work in progress, always changing and improving.
 
Thanks for the compliments! Definitely a fun boat, and it works great for fishing and flounder gigging, too!


When I initially built the boat, I knew it needed a stomp grate, but I got by for about a year or so without one. Then, I got something fouled in my intake grate on the river one day, and had to idle about 5 miles back to the landing. So, I knew it was time to make the stomp grate.

Having owned a Sea Doo Speedster, I was familiar with their design, and wanted to incorporate something like this on my boat. Scan 2.jpeg

So, I ordered a few of the parts from Sea Doo. Specifically, the tapered rubber bushing, and the 2 plastic half-collars that clamped the cable in place in the thru-hull fitting. I also ordered the plastic nut for this assembly, as well as the cable end fitting to attach to the weedless grate.
Scan 1.jpeg


However, I was not able to find that wedge-shaped piece of aluminum with the internal threads, that bolts to the top of the intake scoop, for the cable to fit into. I looked for a while, and then decided to just make my own.

Also, I found that the plastic nut from Sea Doo was not an NPT thread, it was some screwy thread, I have no idea what pitch it was, or if it may have been a metric pipe thread.

So, I tossed that part aside, and instead used a plastic 3/4" NPT plug, drilled a hole in the center for the cable to fit into, and then shaved a little bit of material from the inside, for the plastic half collars to fit in.

Also, I had to make the threaded thru-hull fitting, with 3/4" NPT threads for the plug.

So, I proceeded with some large diameter solid round aluminum, and I contoured the bottom of it so that it would fit the top of the intake scoop, and be perpendicular, not skewed to the side.

I center drilled it for the diameter of the cable, then, I machined a taper in it, to fit the taper of the rubber plug, and finally, I cut 3/4" NPT threads.

Next, I had to have a way to secure it to the intake scoop. So, on the bottom side of this block of aluminum, I drilled and tapped for 1/4" threads.

Because of the contour shape on the bottom of the block of aluminum, it had to be positioned a certain way to remain perpendicular, but how to do this AND get the correct location for those blind holes?

Simple.....I took a couple of 1/4" stainless screws, cut the ends off, then ground them to a sharp point. I threaded the blunt end into the threaded holes of the aluminum block (basically, I made a set of transfer punches) I positioned the block of aluminum where it needed to go, then gave it a light tap with a hammer, and I had my locations for my mounting holes.

Using RTV ultra black, and some taper-head phillips stainless 1/4" screws from the underside of the intake scoop, the block of aluminum was secured in place. Then the cable assembly was installed with the locking half collars, the rubber bushing, and the 3/4" plug cap, with RTV applied to the tapered end of the rubber plug, as the sea doo manual calls for.

Once it was done, this is what it looked like:

A few shots of the thru hull fitting, with cable installed, you can see RTV used to seal under the fitting, as well as the 3/4" NPT plug. 100_0099.JPG

100_0100.JPG

100_0103.JPG

A shot from the underside, showing the mounting screws:

100_0108.JPG Also note the cable end.

Next, I needed to make the intake grate pivot. I cut all the tines loose from the factory aluminum grate. I kept the front end of the assembly. Next, I took some 3/4" round stock, and cut 3 pieces about 1/4" thick from this. Then I welded these 3 pieces onto the front flange of the intake grate, one on each side, and one in the center. This would create a pivot point.

100_0105.JPG

Then, I took some 1/4" thick by 3/4" wide stainless flat bar, used the belt grinder to remove the corners and do some shaping and rounding of edges, and made 4 new tines, and drilled a hole at the back end of one of them for my cable end.


Lastly, I needed a control lever at the console for operating the grate. Using the same concept as the reverse gate lever, I came up with this: 100_0101.JPG

As you can see, this lever is bronze, as are the other control levers. To operate, cut off the engine, then swing the lever down. This pushes the back end of the intake grate down by about 4", allowing debris to clear itself. Return the lever to its upright position, and it retracts the grate.100_0106.JPG

Once all of this was done, I performed a watertight integrity check (fill boat with water until it's above the area you want to check for leaks) and found it to be OK, no leaks.

Works like a charm, and it's simple to operate!
 
All kinds of awesome !

More and more i'm starting to recognize these jet builds.
 
Here's a couple of videos that compare the TS1000 2 stroke engine to the 4 stroke High Output.


2 Stroke vs 4 Stroke Pt. 1:
https://www.youtube.com/watch?v=hfPFCA9wjj4


Part 2:
https://www.youtube.com/watch?v=0dsxNAN0QL8
 
Great post, great project. Thanks for sharing it.

Couple questions for you as I'm contemplating a project just like this.

1. You mention in one of your videos that you didn't use the fiberglass bottom. Was there any particular reason for that? Was it simply the metal shoe and your fabrication skills made it unnecessary, or that you saw a big downside to using/incorporating the fiberglass bottom into the project?

2. I've got a 110hp 787 seadoo motor that I'd like to use. The 4 stroke motor you put in your boat is obviously much quieter, you picked up some top end, and it seems like the hole shot is a little better. Any other feedback you can provide between the two? I've got the 787 motor, so I'm probably going to start with it. If you were to stick with the 2 stroke what would you have done differently?

3. How much water do you need now (with the 4 stroke) and did you need then (with the 2 stroke) to get up on step?

Thanks again for a great project. Your fabrication skills are impressive, and far exceed mine. Nice to see another functional boat getting used and enjoyed. I hope my project gets there quickly.

Thanks
 
Klein, maybe I can answer some of your questions based off my build.

1. On the Seadoo motor / pumps splined shaft alignment is going to be more critical vs. the Yamaha's love-joy type coupling so it may be easier to avoid that mess my fabbing the glass hull into the bottom of the jon boat. Usually the joint looks like crap and I would suspect corrosion issues down the road if used in bracket waters. I chose all aluminum on my install, including making the pump inlet, which was a bit of a pain but also a fun learning experience.

2. On mine when I had the exhaust exiting above the water line at the pump it was louder. I've since ran the exhaust down and out of the pod and it's much quieter even though the exhaust is still out of the water at speed.

3. On mine I need 30' of 2' of water depending on where the trim tabs are set. Before adding the tabs it was 20' but it seemed to dig a bit deeper.

Jamie
 
Thanks Ranchero,

I just checked out your build, another great project. Thanks to both of you for chronicling them so well.

You've hit on my concern with the pump/engine alignment. I'll try to stop hijacking this great thread.
 
Ride_Klein said:
Great post, great project. Thanks for sharing it.

Couple questions for you as I'm contemplating a project just like this.

1. You mention in one of your videos that you didn't use the fiberglass bottom. Was there any particular reason for that? Was it simply the metal shoe and your fabrication skills made it unnecessary, or that you saw a big downside to using/incorporating the fiberglass bottom into the project?




Originally, I did plan to do the 'cut and splice' method (cutting the fiberglass bottom out of a ski and doing some glasswork, and making a flange to bolt it into the bottom of the boat) But, I'm a better welder than a fiberglass man, so, I didn't have much confidence in that plan. Also, fiberglass and aluminum have different flex rates and yield strengths, which may not be a problem on smooth water, but here in a marine environment, the wind is ALWAYS blowing, and it is seldom glassy, it's almost always choppy.

Thinking back, I can't remember if it was my idea, or my friend's idea to go with the XL1200 pump. I'm thinking that it was suggested to me by my buddy who is a jet ski mechanic, that I bought the ski from. But anyhow, I had to buy that in addition to buying the Tigershark for 600 dollars. I think the entire XL1200 pump assembly, including impeller and driveshaft, cost me about 800.

Cut and splice would have been a little more difficult, although, having to build that wedge shape in my cutout to accommodate the slope of the pump was a major PITA (wouldn't have been so bad if that had been the first thing we did, where we could have had the boat upside down, instead of having to work upside down!)




2. I've got a 110hp 787 seadoo motor that I'd like to use. The 4 stroke motor you put in your boat is obviously much quieter, you picked up some top end, and it seems like the hole shot is a little better. Any other feedback you can provide between the two? I've got the 787 motor, so I'm probably going to start with it. If you were to stick with the 2 stroke what would you have done differently?


The one thing I would have done differently would have been to use something besides a Tigershark! There's a reason why Arctic Cat no longer makes Tigershark. They need to stick to what they know...snowmobiles. So, if I had it to do over again with a 2 stroke, I probably would have bought an XL1200 outright, then I would have had the engine, as well as the pump.

Also, one thing I would suggest to make a 2 stroke quieter, is to build your jet unit tunnel large enough where you can route the exhaust outlet into the tunnel, where the sound is absorbed into the water being thrusted out of the jet pump. Also, use a rubber curtain around the back end of the box, notched to fit the pump nozzle. This acts as a baffle for the sound. You can see this in my "American Jetboat- High Output" videos...(I think it's episode 4) This is what Yamaha does with their 4 strokes, and it is very effective. On my 2 stroke configuration, we simply had the exhaust routed right out the back of the boat. However, that platform did help to minimize the sound a great deal when the boat was in the water. Still, the 4 stroke is a fraction of the noise level of the 2 stroke.

The 787 is a good engine, BTW. The 951 is a miserable POS, don't use one of those, everyone I know that ever had a 951, had nothing but problems. and again, avoid tigershark. Mine ran good when it ran good, but it was a very tempermental engine that had a history of issues, even being rebuilt 5 times in the 6 years I had it. I'd get about 140 hours on average, and then I'd have to rebuild it. With this 4 stroke, I only need to lift my engine cowling to do maintenance every 100 hours, and that's to change the oil and plugs. I bought it with 68 hours on it, right now, I have 85 (I did change the oil twice, once I got it running, though, simply because it sat for a while before I bought it, and I wanted to run the old oil out)

You may need to experiment with impeller pitch that allows for a good combination of hole shot and top end, although, you can never have the best of both worlds. If you're operating in shallow water, or carrying heavy loads, you may want to stay with a lower pitch, for better planing, and planing off at lower speeds. If your boat is going to be lightweight, and you operate it on flat, deep water where you can run at WOT a lot of the time, you may want to go with a higher pitch. Impros is a company that can adjust the pitch of your impeller to your specs, as well as being able to rebuild impellers with nicks, dents, and worn-down O.D.





3. How much water do you need now (with the 4 stroke) and did you need then (with the 2 stroke) to get up on step?

Initially we were worried about the added weight of the 4 stroke requiring more draft. But, because of how we have the exhaust system routed, we moved the port side fuel tank, and the 120 lbs it weighs when full, forward by about 2 feet. So, this seems to balance it out somewhat, as it doesn't draw any more draft than it did before, which was a surprise, and a relief, to me.

I need 8-10" of water to be able to float. With 10-12" of water, I can idle. I can plane off at that depth, too, but at that depth, it must be done quickly, and not over shells or gravel, as there is the possibility of the pump ingesting foreign objects. Once it's on plane, it only needs about 4" of water. But always remember that just because you can cross an area at planing speed, you must always know at what point you have to back off, because if you have to slow down to displacement speed, it can get ugly.

Thanks again for a great project. Your fabrication skills are impressive, and far exceed mine. Nice to see another functional boat getting used and enjoyed. I hope my project gets there quickly.

Thanks


Well, thanks for the input and compliments. Glad to help out any way I can with advice or other info about the design and other idiosyncrasies that come along with such a project. Hopefully, I can save others doing such projects a lot of needless time racking their brains trying to figure things out through trial and error, like I had to do.

For further questions or info, y'all can contact me at [email protected]
 

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