Diesel 29 CC. What socially acceptable drive would be recommended?

Otseg · 09-20-2005, 05:56 AM

Diesel 29 CC. What socially acceptable drive would be recommended?

I am getting ready to build a new boat with diesel power. Previously I did a 420 Yanmar with a Hamilton water jet (34 Kts.) and a 315 Yanmar 12 degree straight inboard, (30 Kts.)

I feel a need for speed. The obvious choice would be a stern drive and suffer the frowns from people when I suggest that the boat will be kept in the water or a surface drive and observe the horrified looks from the die hard fisherman envisioning that cleaver prop sticking out past the transom.

Any suggestions here?

captainjay · 09-20-2005, 06:43 AM

Volvo ocean series drive they have a composite case.

SeaJay · 09-20-2005, 07:41 AM

You want the speed, go with the stern drive and deal with the maintenance issues.

captainrich · 09-20-2005, 08:41 AM

Look itno Pulse Drive, in Pompano Beach, or Smith Powerboats uses an under the boat surface drive in a tunnel called Power Vent.

Madisonk · 09-20-2005, 09:18 AM

I was warned by everyone about the Bravo III and I bought it anyway. I have 5 seasons, 631 hours all spent in the saltwater in a marina with alot of electroysis and I don't have a spot of corrossion or a single issue yet with this drive. I start the season with new zincs and change them mid summer. Change the drive oil and pull the drive once a season and you should be fine.

jbg108 · 09-20-2005, 12:47 PM

what kind of boat are you building?

285exp · 09-20-2005, 01:18 PM

Quote:

captainjay - 9/20/2005 6:43 AM

Volvo ocean series drive they have a composite case.

Ocean series only available in gas.

Why would you give a rats behind about what is socially acceptable? Why not try choosing the drive based on what is best suited for your purpose?

Brewhedd · 09-20-2005, 01:32 PM

How did the water jet work out? I would be hesitant to use an outdrive in your case, but that's me. I guess if you went Merc and popped for their anti corrosion system (Mercathode) and did the PM's you might be ok.

Otseg · 09-20-2005, 02:27 PM

Another one of these is what I am building.

http://www.forumpictureprocessor.com...eck%20view.jpg

http://www.forumpictureprocessor.com...tbd%20Side.jpg

I am very familiar with the pulse drive, and I have heard good things about Don Smith's Power Vent from someone I respect. They may be a "little out there" for what I want.

Some years ago I built a boat with a combination stern strut/rudder combo that Harry Schoell designed. It was a bronze casting that bolted to the transom. It achieved a 6 degree shaft angle and the efficiency was way up there. It worked really well. After proving its value, Harry got bored with it and moved on to the next idea. Pulse drive was one of them.

Regarding social acceptance, I personally missed that boat, and I don't have to worry about my resale value.

This project is simply a precursor to the next project and the next project. Some of those boats built just for me I never got my money out of.

Otseg · 09-20-2005, 02:50 PM

The second owner of the water jet could never figure out how maneuver at slow speed and steer in reverse. He made a friend of his buy it from him.

The current owner tied it to a piling with a short line and practiced for two hours, learning the controls. He can thread a needle with it now and really likes it. Almost like flying a helicopter. Its speed is ok and the fuel economy good. With the Transmission installed, you can run it up a beach, then back off by reversing the gear, suck water through the nozzle and blow it out the intake, making a bubble of water to float you off. In the shallow water that the boat can operate in, the fish are unsettled by the Diesel, but in deep water, no problem. Jet wash does not seem to be a problem.

CMP · 09-20-2005, 03:02 PM

The Volvo composite drive is available in diesel-I was offered it but passed. I have a common rail D3, the smallest of all the new Vovlos and I'm amazed at its performance. I aso ran a boat with a 370 D6 in it and again, it is quite a powerplant. I have a huge bias against yanmars-they create their hp with smoke and mirrors and none of them are Tier II as yet. Call your local Volvo guy and go for a ride. That's all it will take...

CMP

shinyo · 09-20-2005, 03:17 PM

If you want to turn a large blade then a Bravo 2 is your best bet. if you only need the torque to give speed then I would go with the Bravo 3. The corrision issue has been resolved.Use only Merc's anodes and if the current is less than 2 knots at your dock,then the Merc cathode system is worth a look.The Bravo 2 is a bullet proof set-up and can really take the loads of a big prop.

Knot Tight · 09-20-2005, 05:42 PM

Sorry to derail, the above pictures look nice and it is what I am looking for can you tell me who the builder is and a range of $$$. I promise I won't get my order in before yours.

jbg108 · 12-26-2005, 07:38 PM

Looks like an Egret. There is one on the boat trader. Very sweet!!!

Hooligan · 12-26-2005, 10:06 PM

Best of both worlds: do a diesel inboard (under console) and run a jackshaft to an outdrive (maybe a volvo duoprop) mounted to the transom. Get the speed and keep the room in the stern.

KCook · 12-26-2005, 10:47 PM

Merc now has a whole range of single prop sterndrives for high output motors. Bravo I is actually at the bottom of this range. Also ask about these over on www.OffShoreOnly.com .

uscgman · 12-26-2005, 10:57 PM

Bravo 2, they are bullet proof and will hold the torque long term of a diesel. They are good up to 55mph also which is more than your hull with see.

spearfish3 · 12-27-2005, 12:01 PM

I would go with a straight inboard with a prop pocket and the same 420 yanmar you had with the jet. I don't know how much room you have in the console, but we have a 540 cummins in a 34 sea vee and I would bet that boat would fly with the same power. Good Luck, it looks like a beautiful boat!

jbg108 · 12-27-2005, 01:30 PM

I was Talking with Carlos from Ocean Runner about an inboard with a pocket. He told me that the pockets loose a great deal of efficiency over 30kts because of water flow. It does not sound right to me, I would think the shallow prop angle to be a huge plus. A Cape Cod 26 with the 440 Yanmar is a 36 knot cruise with the pocket.

spearfish3 · 12-27-2005, 02:20 PM

Our sea vee is supposed to gain speed with one and my friend is building a 70ft custom and they are supposed to gain 2 knots by going with the pockets. Our boat tops off around 35 kts, but my friends custom is supposed to top out around 46-48 kts according to tank tests and weights so I don't really believe that carlos is right. Also just look at all the new sportfish boats, almost all of them have pockets now.