Mainship Bowthruster

[Taughtline]

Planning on installing a bow thruster in our 34' Mainship II in January. Curious if any MSII owners have done so. I need to order it before we pull it out, but I'm concerned about determining the thru hull access for the tube. The sole in the v berth seems like it will be in the way. I'll be doing all the work myself. I could measure it ok if it was on the hard, but tough going while it's wet.

 

[RT Firefly]

Greetings,
Welcome aboard.

 

[bluemainship]

You got to cut about 16 inchs

 

[Taughtline]

Not sure what the 16" refers to. The thruster I'm installing has an 8" diameter. I'm trying to confirm the exact location of the thru hull. If that's the 16 you're referring to, I'm still confused! (There are those who would say that is a constant state)

 

[bluemainship]

You need clearance to glass the tube too the inside of the hull the floor is in the way

 

[KenM]

For what it's worth, my MKIII has a bow thruster under the V berth. Plenty of room for the thruster and battery.

 

[Taughtline]

Thank you for the responses. To BM - if the thruster is pulled back from the bow a bit, would that put the tunnel below the sole?
To KM - did your installation simply require a cut out access thru the sole?

 

[jbbmillar]

Tunnel Entry Radius - something to consider

I think it was Steve Cyr of Stella Blue "fame" who indicted that paying attention to the factory recommended tunnel edge radiusing improved performance. As I recall, he said Mainship installed the thrusters with too sharp a corner and that his performance improved when he fixed that.

Mine is too sharp, but I ran out of time on the last haul out. May try to rework next time.

Jamie
Mainia, 02 Mainship 390

 

[bluemainship]

The top of my tunnel is even with the sole

 

[Taughtline]

Thanks for the note and the photo. So your anchor locker has the power unit mounted to the sole, or is the sole cut out so the PU is mounted directly to the tube? Also wondering what the best method of determining exact location of the thruster tunnel - both inside and outside. Yours appears to be well forward. I feared the entire unit would have to be aft of the anchor locker, thereby standing in the sole area under the v berth - making the three storage doors impossible to open. I appreciate your help.

 

[Taughtline]

Thanks for the input. I've seen a number of photos showing bow thrusters with an "apron" built out on the leading edge to divert water from the trailing edge. Have read where it really helps, and a couple who felt it didn't make any difference. I'm really looking forward to the project. We've had our MSII about a year now and have done many things to her, and enjoying the ride!

 

[jbbmillar]

My thruster motor is accessed through a horizontal panel under the v-berth, just aft of the anchor locker bulkhead.

 

[Heron]

Search Bow Thruster Installation on Google. Several videos, and how to's there that should be helpful:

VETUS BOW THRUSTER INSTALLATION PROCESS

 

[bluemainship]

The PU mounts to the top of the tube. Mind is 16 to18 inches aft of the anchor locker

 

[0025RLL]

Is it possible to add more thrust by changing the blades in the thruster? I have a 2001 390. The thruster works well as it is, but I'm told that it will provide more thrust if you change the number of blades. Has anyone had any experience with this modification?

Thank you

 

[Highnoon]

Hello,
Just joined the forum and also installed a Lewmar bow thruster on my 79 Mainship II. We installed the tube just forward of the access door to the locker, top of the tube is about the hight of the cabin sole.
I removed a portion of the locker floor, maybe 2 feet and all the way to the tabbing on the hull, plenty of room to glass all the way around. We are so happy with it, no more lock to lock and banging the poor old gear behind the Perkins. Let me know if I can be of any assistance, I took lots of pictures and measured 100 times before the sawzal came out.
Good luck