47 Bow and Stern Thrusters-gctid815623

[mmichellich]

A firend wants to add bow and stern thrusters to his 47. He has locked on to water jet propulsion believing it easier installation. I recommended he find out what works well on a 47 with traditional prop in tube thrusters. So in ft pounds or other what have you found is needed on a 47 for bow and stern thrust? With that data he can determine if water jet thrusters can compare. Help please.

[higgins_jr]

Mickey, I have a conventional Craftsman brand bow tunnel thruster only. It's marketed in the USA as C Marine. It's 95kgf thrust/5.95kw if I remember 5hp. Of course in a really strong cross wind, most thrusters struggle. I did investigate those jet type water thrusters before I installed, and they were megadollars at least down here. I remember the install, the pump and central piping throughout the boat was cumbersome and space hungry.

Hope it helps. Cheers

[higgins_jr]

Mickey, further to my post, your friend needs to figure out where the plumbing throughout the boat from the pump and water inlet "scoop". The jet thruster unit I looked at had a central line with a "T" fitting at both ends where horizontal piping went to skin fitting nozzles either side of the boat, bow and stern. If the oversized pump is located in the engine room, getting the central pipe thru to the bow will be a challenge, and will require the removal and probably scrapping of the rear underfloor water tank in the master suite. That tank is shaped into a V in the bow to sit against the hull that leaves zero room under or around the area to get the jet nozzles low enough to be effective.

These installation issues and the significant cost over conventional thrusters quickly eliminated the concept.

Cheers

[Simonsen]

I have Lewmar 185TT 12v bow and stern thrusters and they move the boat just fine.

Derek

[Pacrimrat]

Trusters were at the top of my list for the first few years of ownership, now they're at the bottom.

Over the last 14 years of ownership I can think of about 3 times where thrusters would have made a big difference.

When you really need them in big winds or currents they aren't that effective.

I looked into the water jets and thought they would be great. No time limits on use. But the company that looked the most promising in Sweden went out of business.

[mmichellich]

When we bought our 47, I wanted a stern thruster. I contracted with Delta marine to install it. Left the boat there for a month while I did overseas business. When I was about to return I called to see how they did. Told me boat torn apart, but mgmt would not allow them to cut existing water tank and they insisted on building a new stainless tank. That would almost double the cost and they wanted to mod our contract. They would not perform to their contract so thry had to reassemble everything at their cost. Have lived with zero thrusters for 20 years. Made me a much better boat operator. I did pay Delta for bottom paint, zincs and haul out but no yard time.

[Simonsen]

What water tank would you cut for stern thruster? It's a simple install. I'm assuming you meant bow thruster.

[mmichellich]

I mis spoke, bow thruster. I did not see a need for a stern thruster.

[point2]

I originally had a 5 HP thruster. My advice is not to do that. I pulled it out and went to 10.

The 5 was hopeless in any wind.

Stephan