Jet Drive for 10m tour boat - weed and shallow water solution needed

I know ... but I said I don't want outboards as they have a short life and double the consumption. Everybody wants low priced tours and you can't offer that with outboards when the price of fuel here is 1.10 EURO/liter...

 

Forget about the arnesons, thats not the propulsion for your requirement, and it will NOT hack through the stuff found east of Sulina! Children can walk on it, as we know, a surface prop will get stuck.

The same is valid for the childish nonsense Mr Pierzga likes to contribute again.

As mentioned, I know the conditions you are going to work in, and I have only one solution to provide.
Well, airboat and hovercrafts would work of course, but are far too loud by their very nature.

Interesting craft you found there! A bit small and slow for your purpose, but shows the principle performs reliable. And 50kW for 8kn is ok I think. Something similar is, what I have in mind for your application.

Regards
Richard

 

I just got a message from Schottel and they don't recommend the Pump Jet for weed infested waters... here is what they say:
Dear Sir,

Thank you for your enquiry.

We did not have good experience with Pump Jet and weed in the past.

Therefore we can not recommend our product.

Best regards

Andreas W.
General Sales Manager Passenger-, Work- and Cargo Ships

So back to square one... the good old prop.

 

jet drive for 10 m tour boat

If you are afraid of U/V joint falures you could use Hickmans Sledge ideas. At 60 HPH they must have been pretty good to mave all of that heavy machinery.

www.shareaproject.com/pages/projects/c,s,10,00.html

 

Yap I know about that one but all the surface drives seem to have a problem with different load situations, poor reverse, poor slow speed, noise from the ventilated propellers. At least from all I have read until now with some exceptions.
This is something I found:

http://www.vaartuig.info/workboats.html

They are workboats with Schottel transmission. I know this is heavy equipment but seems strong.

Off topic -

I wonder if anyone here had experience with the air cooled diesels? I refer here at the Deutz 100hp and the Hatz

- how noisy are they?
- can they be sound "insulated"
- what is the price compared to the water cooled counterparts and what are their problems..?

This motors would be ideal for my boat as it will spare me from implementing the rather complex keel cooling. They are low rpm so I guess they last a long time too. Somehow heavy but...

I should move this to the diesel section.

 

Thats a joke!

The entire passenger boat fleet on the Danube uses Schottel Pump jets! And they are the only propulsion on the world market without a measurable suction force. Now YOU tell me that SCHOTTEL does not recommend them in their own environment?

I will call Spey!

Regards
Richard

The air cooled Deutz are amongst the longest living Diesels in the world, nearly indestructable. But due to their very nature loud, very loud. And air cooling means free flowing air, and noise....

BTW

a nice site you put online, my compliments!!!

 

Now that bit about suction force is interesting.
Vaccums don`t suck, the atmospheric pressure pushes. Displace water and or air then atmospheric pressure pushes water or air back in.

 

Schottel and weeds

Well here is the second answer that seals the whole thing about Schottel pumps for me... Sorry Richard and thanks for help in this matter:

Q. Will this system work on shallow water sometimes covered in weeds?

A. SPJ is not suitable to work in weed covered areas. As inlet grid would be closed.

Q. What is the cost of - SPJ 22 and SPJ 15 and how complex is the implementation of this propulsion system.
A. SPJ 15 RD not suitable as only vertical input and engine impossible to be installed vertically. Jet SPJ 22 alone incl steering
50-80 T € ???- i guess this is 50-80.000 EUR?

Q. Will this system work with Deutz air cooled engine -
A. F 6L 91
Q. Does the system require a gear box or reduction to achieve the desired rpm? or is it better to chose a low rpm engine like the Deutz mentioned above?
A. Reverse reduction gear needed.
Q. What is the efficiency of the propulsion compared with a propeller?
A. 50% of an open propeller

Q. We plan to build an aluminium Tour Boat flat bottom with a length of 10m and a beam of 3.2m that will transport 15 people. The speed we want to achieve is - 20 km/h.
A. Speed will be less. Normally 2 thrusters to be installed due to redundancy.

So the price of this pumps is 50.000 - 80.000EURO? they better be made of GOLD plus the efficiency is 50% less than a propeller.

I run a tour company for 16 years now and operate floating hotels, tugs etc I think if I build this tour boat I could sell all I have now and still not be able to finish this one. The boat is making 400 hours/year... what can you charge per hour to make a 200.000 Euro boat profitable? and for how many years?

Anyway the conclusion is the only reasonable propulsion system is the propeller. They idea of a stern drive starts to look appealing but I have no clue what combo of diesel engine and sterndrive are best for commercial use? Any advice on that would be great.

 

Perhaps interesting for you to consider. Dont like the rudder shape but the shielding looks simple

 

Look here for proven diesel/stern drive combos:
http://www.steyr-motors.com/technical/technical.htm

 

Some more unusual diesel marine equipment and barges www.goodsdirect.net/outboards.htm

 

Hi CDK,

Got an offer two years ago from Steyr:
MO174V40 package BRAVO II – 23.210 euro + TVA (24%) - 28.500 EUR. ( aprox 170 hP ) - 34 329 USD... big money...

And an offer from Volkswagen Marine:
TDI 165-5 Bravo III - 18056 EURO + VAT (24%) - 22380 EUR - 29 778 USD

A 5000 EURO difference .... Anyone here with VW Marine engines experience?

A Suzuki DF175 outboard would be about 17.000 EUR similar with Yamaha.

The advantage of VW would be available spare parts as these are easy to find in Europe. Steyr is reliable and top of the line...actually probably the best diesel in its class at the moment but the service parts are not as common plus the premium you have to pay for it.

I would expect the engine to last about 5000 hours without major repair so that would be about 10 years of use and about 50.000 litters of diesel that is an equivalent of 55.000 EURO fuel...

If I use an outboard ... say it will last that long I will use 80.000 litters of diesel or about 88.000 EURO

A difference of 33.000 EURO or 43 909 USD... between diesel an gas.

That's the way things are in Europe.

Any better options?
What do you know about Bravo III legs?

 

The SPJ is not cheap, and has a efficiency problem (48%) but is the only propulsion you have in your environment.

Forget about all the comments. Why are ALLL , and Alll of the cruisers in your area are using Pump jets? They are all too dumb to grasp the facts?

 

Some nice looking Tourboats from the Netherlands..


http://www.scheepsbouwkunst.nl/kenau introduction1.htm

 

Converting an off the shelf VW Passat engine or building small quantities of Steyr engines explain the 5K euro difference.

The comparison with a Suzuki is a poor one: 5000 service hours is beyond the capability of any outboard engine, you'll wear out at least two.

Fuel prices in Romania seem to be in line with other EU countries. Is lower taxed fuel available, like red diesel for agriculture of blue diesel for the fishing fleet? I know from my own experience that VW engines are quite happy with heating oil....