Stern Thruster Installation Cost?

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Hydrospud

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Jun 2, 2022
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Can anyone give me a "guess-ta-mitt" on the cost to add a stern thruster to a 36'-44' trawler? It will need to be operated from upper and lower helms. We are in the process of looking for a trawler and was wander what it would cost?
Thanks
Peter and Deb
 
First, welcome aboard. I have put stern thrusters in two boats. The first one was a Sidepower and the second one is a SideShift. I like them both. The SideShift was an easier install and on our current boat the only way to fit one in. The cost back in 2016 for the Sidepower was about $5,000 for the parts, maybe a bit less. The SideShift was about $4,500. I did the installation on both myself. Really not difficult if you have basic DIY skills and are willing to cut an 8” hole in the hull below the waterline for the Sidepower. The SideShift mounts above the waterline so no holes below the waterline. Also the SideShift has wireless connections to the joysticks so a bit easier install since you don’t have to run control wires from transom up to the helms. It also came with a wireless remote that costs extra on the Sidepower. I liked both systems and probably would have gone with Sidepower in our current boat if it would have fit, but after doing the install on the SideShift I now would go with it since the installation was simple.
 
I had a stern thruster added to my 42 Nordic Tug in early 2018 - Side Power, single helm.

The total cost was about 9-10K, as I recall. Work was done in Seattle.
 
I spent about $7500 USD on the installation of a SidePower SR80/185T retractable stern thruster in 2012. The work was performed by a boat yard. It was a tough and expensive decision for me at the time. In retrospect, I can say that it has been the absolute BEST single boating equipment investment I ever made. Having lived with it now for 10 years, I can say that I would not hesitate to spend $15k for the same installation, were it to cost that much today. Find the means to do it. You will never come to regret it!


Since the time my stern thruster was installed, I have become very adept at handling my boat and can easily dock in situations where I used to rely on the thruster. Nevertheless, countless weird situations arise due to weather or constrained marina/dock space, etc., etc. It's great to know you have the thruster to rely on. It gives great peace of mind and I expect has helped me avoid some gelcoat repairs -- both to my boat and other people's boats.


Good luck with your search!
 
Have both bow and stern on a NT42. I’m a newbie to power so a steep learning curve as it’s much different on sail. In the process of unlearning the techniques ingrained by decades. The owner of the yard we were in took me out several times. Said you understand walk and wash but not power. Until you do put the rudder amidships and don’t touch it. Just steer with bow and stern thrusters. Been in/out of several slips where’s there’s a finger every two boats and inches between the boats. The bow aims you but to pivot effectively the stern is a boon. Yes it’s a crutch for this newbie on a single screw boat but worth every penny.
 
remember, if your thrusters are electric you need batteries to support them.
I moved both of my thrusters to the house batteries. (3X4D) Reason, the Cummins will shut down at about 10.6vts. Better to be left w/o thrusters than without a main engine.
To that end, I added a meter to measure house batteries voltage at the helm station.
In an emergency I can parallel all the batteries, with the understanding, this is a last resort and I may lose the main engine too.

Two things to remember, neutral is a gear, use it. Apply power, neutral, drift to see what your boat is doing, adjust.
Is that 2 or 3 things.

Recommendation: learn to "back a fill" and to back straight. Once you can back straight, you can learn to modify your technique to put the stern where you want.

Power is used to enhance the movement. Power can override the thrusters.
 
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I put in 2 AGM for each thruster since mine are 24 volt. They are separate from any other system.
 
Have both bow and stern on a NT42. I’m a newbie to power so a steep learning curve as it’s much different on sail. In the process of unlearning the techniques ingrained by decades. The owner of the yard we were in took me out several times. Said you understand walk and wash but not power. Until you do put the rudder amidships and don’t touch it. Just steer with bow and stern thrusters. Been in/out of several slips where’s there’s a finger every two boats and inches between the boats. The bow aims you but to pivot effectively the stern is a boon. Yes it’s a crutch for this newbie on a single screw boat but worth every penny.

I chartered a Nordic 42 with bow and stern thrusters before I bought my 37 with bow thruster only. I came from a twin engine background and really relied on the stern thrusters to get the 42 where I wanted it to go. For the most part at least. Between the windage and the mass of the 42 the electric thrusters couldn’t overcome more than a mild breeze in the marina before I found myself having to spring off the dock.

Still, when I bought my 37 I was pretty sure that I would be adding a stern thruster before long. But as I’ve gotten more adept at moving the stern around with the prop walk and that big old rudder, it just keeps slipping down the list of things to spend money on.

In fact, developing touch with the helm has been one of the most fun things about learning my boat. These days I feel like a big star on Marina TV every time I wave off the helping hands and come in to kiss the dock and step off with a line in hand. I’d feel like I was cheating if I sprang for the thruster now!
 
Truly hope to get there. In the past mostly boated in windy areas so thrusters were ineffectual. The throttle linkage in all prior boats was mechanical and engine HP modest. Now with fly by wire and 540hp it’s much harder to be delicate. Boat likes to back n fill clockwise but ccw requires thrusters to pivot in place. Windage is different as well. High aspect fin keels pivot with the bow falling off. The NT pivots a bit but also slides to leeward.
Will crawl before I walk. But for now appreciate having both thrusters.
 
Truly hope to get there. In the past mostly boated in windy areas so thrusters were ineffectual. The throttle linkage in all prior boats was mechanical and engine HP modest. Now with fly by wire and 540hp it’s much harder to be delicate. Boat likes to back n fill clockwise but ccw requires thrusters to pivot in place. Windage is different as well. High aspect fin keels pivot with the bow falling off. The NT pivots a bit but also slides to leeward.
Will crawl before I walk. But for now appreciate having both thrusters.
Don’t get me wrong, I wouldn’t tear one out if I had one! Just don’t miss not having it as much as I thought I would.

Don’t the electronic controls usually have a low-speed mode that gives you finer control over the low RPMs? I was thinking of retrofitting to replace my mechanical controls so I could use a remote helm on the bow and hadn’t thought about losing touch as a concern.
 
Has a fast and slow idle. Inadvertently it will be left in fast idle which is terrible for close quarters. Now checking that is another thing on the list before entering a marina along with the thrusters. Unlike a mechanical control it’s difficult to tell neutral from idle. No feel. There’s a rudder angle indicator at the pilot house helm but not at the flybridge where I am for docking due to better sight lines. The sailboat was 2 full turns lock to lock and a very big wheel. The NT wheel is much smaller with more turns lock to lock. I never looked at the controls on the sailboat. Everything by touch. It will come but for now need to glance down on the NT. Knock on wood have yet to hit anything but not facile docking.
 
I think the OP was asking the cost to install a stern thruster, not whether or not you need one. My take is if you want one and can afford it then do it. I am tired of people saying you don’t need thrusters and should just learn how to handle a boat. As we get older we are less nimble and not as strong so thrusters make sense. We put a thruster on the stern of our last boat because by the time I would get down from the flybridge to handle a stern line the boat had usually blown off the dock, wireless thruster control and the boat would be back on the dock. Our current boat has a walkthrough windshield. My wife said she will never go onto the bow to handle lines, she is more unsteady than when she was younger and she wasn’t very steady then. So I put bow and stern thrusters on this boat, not because I don’t know how to handle a boat, I taught boat handling for the CG for 30 years, but because with thrusters we don’t have to rush as much and don’t have to be as strong. When you have to hurry is when mistakes and falls are more likely to happen. A fall at our age could end our boating careers, then just shoot me and put me out of my misery…
 
I think the OP was asking the cost to install a stern thruster, not whether or not you need one. My take is if you want one and can afford it then do it. I am tired of people saying you don’t need thrusters and should just learn how to handle a boat.

You are completely correct that these discussions do tend to drift like a tug with electric thrusters in a cross breeze, and also that there is not much down side beyond the extra weight of the batteries to installing a stern thruster if you can afford it. But I wasn't saying that one should learn to handle a boat *instead* of getting a thruster. Just commenting on how surprised I was to discover that I didn't really need one after I got the feel of my boat, and how much developing that feel has been a part of the fun of boating to me. I wonder if I ever would have discovered that if my boat had come with a stern thruster. I'll probably add one anyway during a future haul out, but it's been a kick learning my boat without one in the meantime.
 
One of the reasons for blown fuses is inadequate batteries and increased dust I’m told. In your budget add in really good batteries and charging. Prior owner was using flooded. Fuses blew with moderate use. Replaced with lifelines and no further issues.
 
Thrusters

We just installed Sideshift bow and stern thrusters on our 42 foot Hershine, and I can say, so far it’s a joy to have them. My numbers below are in Canadian dollars…

$4900 plus taxes per unit
2x AGM batteries for each unit @ $300 each
Assorted wire approx. $600
I did the electrical work myself, but paid my boatyard to do the physical install of the units. About a day of labour for the 2 units. ~$1000

That adds up to $13,800… I’m sure I forgot something, so safe to say $14-15,000CDN, so roughly half that for just stern.
 
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I have added them to my current and last boat. First one was a Sideshift, 2nd was a lewmar. I feel the "tunnel" gives it a bit more thrust than the "open" design of the Sideshift.
Cost is really going to come down to a couple BIG pieces.

1. self-install or shop
-if shop, count on about 2x min the cost of self.

2. current setup on boat.
-Do you currently have batteries easily accessible for use of the thruster?
-Do you want to keep the systems separate from other ships' systems?
-Distance of runs to make everything happen

I have a dual station boat, but I NEVER use the thrusters from lower helm. I drive from upper 95% of the time and 100% of the time for docking. So the need for dual station setup wasn't needed when I added the setup.

I assume the boat already has a bow thruster, so will you want to integrate with that one or have sep. stand-alone controls? I have a older Wesmar in the bow and it's a beast! the boat JUMPS when I kicked that one on... :) I wanted a single set of joysticks, single power on/off and control in one place. Had to get a bit creative with some relays, but has worked flawlessly for ~3 years now...

My suggestion for you would be:
1. get a 24v option if you can, tons more power!
2. if you are even close to the 75% max range for the thruster, get the next size up!!! Nobody ever regretted having too much thruster! As someone else mentioned, they were on a boat that had one that was basically useless in any sort of wind... :(

So there isn't really a short answer without knowing more of what you have and what you want...

Pic attached shows the cost of the "kit". But you also need to figure cost of wire, batteries, misc. "stuff", possibly secondary charging source, etc, etc...
 

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I was going to go with the traditional Sidepower thrusters in our Formula until I started looking how the installation would go. To do the bow tunnel I would have had to relocate the forward A/C, not horrible but still a PITA. To do the stern thruster I would have had to relocate the water heater, genset muffler and about 6 or so hoses and if I moved all that stuff it would have made any future maintenance back there impossible. So I looked at SideShift thrusters. They are really easy to install, about a day for each. They do have exposed props so they may not be quite as effective but they work fine so far. The install on the bow thruster was done by me and my wife. The stern thruster by me and a friend since the stern of my 41PC has terrible access, really tight. Each took about a day to do. The cost for both was about $9,000. 4 AGM start batteries was about $1,000. Some misc wire and connectors that I had in stock. To have the traditional thrusters installed was going to cost me $23,000. I feel that I came out way ahead with the SideShift. I took the money that was left over and used it to go towards the new canvas and cockpit upholstery.
 
We just put a Side Power stern thruster in our Heritage East 36. It was about $10,000 for a yard to do the installation.
 
Take a look at Dockstarthrusters.com - We had both bow and Stern on our 34' CHB Trawler, and down the dock from ours was a 42' trawler with one on the stern.

Affordable, rechargeable, radio remote control - they could spin out trawler on a dime
 
I installed a Sideshift stern thruster on my Mainship 390 last year. The total cost $6,909. It included installation of $1,000. I had it connected to my own house batteries (I have 6 six volt Trojan golf cart batteries, lot's of power). Also installed control switches on both upper and lower helms to control both my original bow thruster and the new stern. Also got a remote key-fob that controls both bow and stern. Best addition to the boat since I bought it 8 years ago!
 
Take a look at Dockstarthrusters.com - We had both bow and Stern on our 34' CHB Trawler, and down the dock from ours was a 42' trawler with one on the stern.

Affordable, rechargeable, radio remote control - they could spin out trawler on a dime

I recently put both a bow and stern Dockstarthruster on our boat, have not had a chance to use yet, but very easy install, no wiring required and under $5000 for both.
 
I installed a Sideshift stern thruster on my Mainship 390 last year. The total cost $6,909. It included installation of $1,000. I had it connected to my own house batteries (I have 6 six volt Trojan golf cart batteries, lot's of power). Also installed control switches on both upper and lower helms to control both my original bow thruster and the new stern. Also got a remote key-fob that controls both bow and stern. Best addition to the boat since I bought it 8 years ago!

You have a Dockmaster??
 
I have a SideShift stern thruster made in Canada. Don't know what a Dockmaster is.
 
I have a SideShift stern thruster made in Canada. Don't know what a Dockmaster is.

It is a wireless controller for fwd and aft thrusters, crawler speed fwd aft, anchor windless up and down
 
My SideShift thrusters came with a wireless remote control but only for the thrusters. Works great.
 
My SideShift thrusters came with a wireless remote control but only for the thrusters. Works great.

I like mine because it controls the thruster and the crawl fwd and aft.
But, controlling the thrusters is a friggin benefit for single handed
 
Stern thrusters

Can anyone give me a "guess-ta-mitt" on the cost to add a stern thruster to a 36'-44' trawler? It will need to be operated from upper and lower helms. We are in the process of looking for a trawler and was wander what it would cost?
Thanks
Peter and Deb

Can’t speak to internal stern thrusters but you can have a external stern thruster installed for about $9,000,total cost. It looks very interesting. I’m considering it. All the benefits of a thruster but no holes in the boat and it’s protected by your under structure. I’d look into it. You can get some boat show deals.
 
Can anyone give me a "guess-ta-mitt" on the cost to add a stern thruster to a 36'-44' trawler? It will need to be operated from upper and lower helms. We are in the process of looking for a trawler and was wander what it would cost?
Thanks
Peter and Deb
We have a Mainship 390 single with a Bow thruster I added the side power external unit myself, relatively easy install, the unit was $3,200.00 Canadian the I box Fuses wiring and shut off were $500.00 Canadian each Control joystick are $330.00 Canadian and I bought the Remote negating the need for a joystick on the flybridge. $550.00 Canadian, I then installed 2 Group 27 starting batteries with their own Charger which was $750.00 Canadian. Best investment we have made
 
Can anyone give me a "guess-ta-mitt" on the cost to add a stern thruster to a 36'-44' trawler? It will need to be operated from upper and lower helms. We are in the process of looking for a trawler and was wander what it would cost?
Thanks
Peter and Deb
Pictures of my install
 

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Yes, we love our thrusters. Just push the joysticks and you go sideways. Saves my wife from having to go forward on the bow, which she doesn’t feel safe doing. It will enable us to keep boating for a lot longer time than without the thrusters. What is that worth?
 
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