Donzi 16 OB Horsepower Questions

[HIGH LIFE]

Anyone know where I could purchase a stainless steel rub rail for a 16' Donzi outboard ? HIGH LIFE

[loudpipes2]

Been stored since 1990 when i brought it!!!06 put new 04 125 merc. New steering new controls new gages split hull inspected installed new fuel cell boat is the balls runs 55 mph all day must sell needs interior only!!!call mark 603 509 3331

[loudpipes2]

If I had the money, I would do a 16 ob with a 150 Honda. Speed ,handling and most of all fuel economy. I could even be enticed to go with the new Honda 90 Honda. The last test I did on it before I left Honda was out standing. Same speed, lighter weigh and better fuel economy the old 90 Honda.

should be 115 merc, or any other merc, motor!!!

[BigGrizzly]

I though they hid that pretty well. I guess Poodle can find anything. I am told in a 24 hour race they stop 4 + less times then the others.

[Donzi Racer]

Donzi racer has one
there is another in Pt St Lucie
there is another in WPB
one in the Grove
one in Key Largo

i'm sure i'll think of a few more

We also sold a 1974 Baby 16 with a 175 hp Merc to a guy from Jacksonville. It was white with teal stripe. Was a few years back.

[Conquistador_del_mar]

I was just wondering the difference horsepower rating on a 16 effect speed, 115hp-150hp-175hp-200hp-225hp-300hp...HIGH LIFE

Michael,
Here is one place. If you buy the longer sticks, it has to go common carrier if I remember right. Bill
http://www.rubrails.com/stainless_steel.html

[MOP]

Hey Matty, any chance this is the spray painted white with lt. blue stripe outboard 16 you're thinking of ?

Mike was that the one that was out in Mattituck?? If not I might be able to get a lead on another one.

Phil

[Donziweasel]

John, by the look of the invoice, the dealer was trying to cover his ass. No coast guard rating, boat not safe, needs hydrualic or dual steering. Did he give you a bunch of greif about putting the 175 on?

[AndyDiSario]

Thank you all for your generous advice!

My wife and I have taken out our Donzi Sweet 16 OB Classic just thrice so far. We found it is a wonderful boat, althought there is a learning curve to conquer for sure, foremost for safety and usability. I've added a swim platform, telescoping ladder, anchors, handles, extra cleats and more. Along with a bigger project at the house (building an extra garage), I've concentrated first on just setting the boat up for our use.

Next, I'd like to work on eliminating chine walking at top speed, which is currently a modest 48 mph GPS. The boat rocks port-to-starboard on its chines near the stern at top speed. I've heard a jack plate may help tune for a better ride and less chine walk. I don't know. I will need to try adjusting the trim tabs more, as well as gain more experience, also. If necessary, I will consider adding adjustable aftermarket sponsons, the same as is used in the PWC industry to eliminate severe chine walk.

After that, I wish to go faster, a lot faster. I'm told the jack plate can help with this. Currently, the boat is powered by a 150 HP Johnson V6 driving an as-new three-blade aluminum prop. In the future (way in the future), I'm currently thinking of attempting to sell the Johnson and repower with a more-powerful two-stroke.

As always, I'm open to all your experienced advice.

Regards,
Andy DiSario
11351 Lake Tree Ct.
Boca Raton, FL 33498
561-479-0578
DiSario@bellsouth.net

[AndyDiSario]

An update: My wife and I had a wonderful day this past Saturday taking out the Donzi. It was a beautiful day, so we circled the Loxahatchee Everglades rim canal here in Palm Beach County, FL. As is typical in the 'Glades, many birds and gators were to be seen and slalomed around. This Donzi Classic 16 is one sweet ride -- I'm really falling in love with it. It jumps out of the hole (pops onto plane), accelerates, rides, corners, even stops so very well with its deep Vee. It's just that top speed is not there yet in my opinion (47.9 mph on the GPS at very best).

The test of my minor mods and upgrades done over winter proved successful. After quite some tinkering with starting fluid and the primer ball to get the Johnson 150 started, the boat performed flawlessly all day. I was ready to experiment with the trim tabs as needed (which are still new to me), but they really were not required. The objective was to try the tabs to help control chine walking, but honestly the boat did not actually chine walk on Saturday. At present I am at a loss to explain why, as we did experience chine walk last autumn in the Intracoastal.

Anyway, my next objectives will be to install Faria depth sounder and volt meter, then a marine 12 volt outlet (cigarette lighter outlet -- adaptive technology at best). Then, seriously, I want to go faster, much faster.

I'm considering a hydraulic jack plate. I'm told raising the motor so the prop runs half-in, half-out of the water will increase speed drastically, and somehow control chine walking simultaneously (?). Of course, a lower water pickup will be required. This seems most unnatural to me, as I'm bred on PWC where jet pump cavitation is to be absolutely avoided; also, whenever I bring the trim up far to expose the prop on the Donzi or our 18' Stingray OB, the prop begins to cavitate, revs rise, speed falls off, etc. What truly is the advantage of a hydraulic jack plate? How many mph can it give my Donzi? Besides not altering the angle of the boat in the water (as does trim), what are its real advantages? Anyone have advice what to expect with this?

Still, the motorhead in me wants to simply buy and bolt on more power -- a lot more power, fitting a hydraulic jack plate between motor and transom while I'm at it, should I be convinced it too is worthwhile. A powerful 2-stroke would be the choice due to its power-to-weight advantages. My big question: Just how much 2-stroke motor can the Donzi 16 OB handle? Will the transom need reinforcement? How is this done? Anyone know a good OB shop with experience doing this, anywhere near So FL?

As usual, advice is appreciated.

Regards,
Andy DiSario
Boca Raton, FL
561-479-0578
DiSario@bellsouth.net

[Just Say N20]

I ran a 16' Laser (the company name before it went to LTV) with an Evinrude 200. The boat had a pad bottom, or the keel did not go to a point, but was a flat "pad" that was about 8" wide. This gave the boat something to ride on when really moving.

The jack plate does a couple of things. It moves the engine back slightly, giving the engine additional trim leverage. You will be able to achieve the same running angle with less engine trim.

It also gets less lower unit in the water, which in higher speeds (70+ mph) is a major source of drag. A properly designed propeller will actually do very well running in a surface piercing situation. It is COMPLETELY DIFFERENT than the cavitation issue with the impeller in a jet pump.

When I first installed the 200, I was running a "chopper" style propeller. This type of prop has a lot of blade area, decent rake, and mine was cupped along the outside edge to give a little more bite. I had to run a decent amount of trim to get the boat running freely. It ran 74 RADAR mph.

After I installed the jack plate, added a nose cone to the lower unit (I experienced "blow out" at 80 mph, where the lower unit punches a big enough hole in the water as it moves through it, that it starves the prop blades for water, and they begin to cavitate wildly loosing thrust, causing very exciting things to happen quickly), went to a cleaver style propeller which are not usually good at providing bow lift, and raised the engine so when the prop shaft was parallel to the bottom of the boat, the top of the gear housing was even with the bottom of the boat.

This allowed me to have less drag, a more efficient lower unit, and run with less trim which was more efficient. When you trim the engine up to lift the bow, it does create less wet surface, but the thrust is no longer exactly in the direction of travel.

I increased top speed from 74 RADAR mph, to 87 RADAR mph by doing these things.

The concept is the same, but I imagine the results would be less because you are running a deep vee hull without a "pad" for the boat to run on. But the principles are the same.

This is the boat (and me, in 1983!). In the video you can see the engine is up pretty high, and does not look excessively trimmed out, but the boat is running very free.

Hope this helps.



http://s26.photobucket.com/albums/c1...erFlyBymov.flv

[Ghost]

That video looks like you've got it dialed in about perfectly, and the surface conditions look about perfect to aerate just enough without bouncing you around. (Though with so little hull in the water, I dunno how much that even matters.)

[Just Say N20]

One other important issue is steering slop. Hydraulic is the best; no play and no feedback against the wheel. On my outboard I ran dual steering cables, tightened against each other so there was no slop.

With a single cable, the actual cable can move inside the housing from the inside of the bends, to the outside of the bends, and this creates play, which allows the engine to oscillate back and forth, contributing to chine walking.

Sorry if this is "stupid obvious" but it seemed like you are learning about new performance issues with the OB Donzi 16, and the steering thing is pretty basic, and very important.

[seano]

photoshop I got ya photoshop right here
is it live or memorex
i forgot about this one but then again ya can't count it
Poodle
I am correct about AMH making a few less than 5 OB's????

The blue boat is mine. It was originally an I/O that was converted. I was going to sell it, but now I am in the process of converting it back to I/O.

I have had a new interior made for it and have purchased the correct controls. I've also purchased a low-hour 350 mag/alpha package for it. Hope to complete it this year, but it still needs alot of work...

[mattyboy]

The blue boat is mine. It was originally an I/O that was converted. I was going to sell it, but now I am in the process of converting it back to I/O.
I have had a new interior made for it and have purchased the correct controls. I've also purchased a low-hour 350 mag/alpha package for it. Hope to complete it this year, but it still needs alot of work...

Nice,

great to hear that one more saved