Stern Thruster on 400

[Newtrawlerowner]

Looking for a company to install a stern thruster on a 2003 Mainship 400 in southern Florida. Does anybody have a recommendation on a company. Also what should I expect to pay?

 

[caltexflanc]

Florida Bow Thrusters. Great service before during and way, way after the sale.

https://www.floridabowthrusters.com/

Have you tried hiring someone to show you how to dock the boat without one? It's a lot cheaper!

 

[Newtrawlerowner]

Stern Thruster

Florida Bow Thrusters. Great service before during and way, way after the sale.

https://www.floridabowthrusters.com/

Have you tried hiring someone to show you how to dock the boat without one? It's a lot cheaper!

Thanks for the referral.

 

[caltexflanc]

Isn't the 400 a twin engine boat? I'm curious as to why you feel you need a stern thruster, having run a few of the predecessor models (including a single) multiple times.

 

[Newtrawlerowner]

Isn't the 400 a twin engine boat? I'm curious as to why you feel you need a stern thruster, having run a few of the predecessor models (including a single) multiple times.

No not a twin. I have a single engine 400.Mainship made both singles and twins.

 

[Conrad]

A dock neighbour had a single engine Mainship 400 with bow and stern thrusters and loved them; he could put that boat anywhere he wanted. (He also had a handheld remote that of course he loved to show off with!)
The stern thruster needed to be offset (I think to port) due to other stuff going on at the centreline but he didn't really notice any difference between port and starboard thrust.
Around here, where bullrails are ubiquitous, some of the usual springing tricks aren't as feasible.

 

[Arc]

FBT. The best. Ask for Tom

 

[caltexflanc]

Interesting. The single 390 we used had a thruster. You could spin that thing on a dime between the thruster, rudder and prop walk. I liked those boats, honest as the day is long.

 

[Seevee]

I have the MS400 single with bow and stern thrusters and find them both useful. In a light wind it's not hard to back in and with the stern thrusters to control the boat within inches.


And a stern thruster is relatively cheap to add, with a lot of benefits.

 

[Newtrawlerowner]

Stern Thruster on a 400

Looking for a company to install a stern thruster on a 2003 Mainship 400 in southern Florida. Does anybody have a recommendation on a company. Also what should I expect to pay?

I got 2 estimates. FBT and E.C. Ruff. They were quite different and both wanted to install more than I needed. E.C. Ruff had a person who only wrote estimates. Still want to do it but rethinking who will do the install.

 

[Comodave]

The worst mistake in installing a thruster is to go too small. A larger thruster will work much better and have to run for shorter times. The cost differential is relatively small. I put a stern thruster on my boat and went one size larger than the recommended size and love it. It was a few hundred dollars more but well worth it.

 

[Newtrawlerowner]

The worst mistake in installing a thruster is to go too small. A larger thruster will work much better and have to run for shorter times. The cost differential is relatively small. I put a stern thruster on my boat and went one size larger than the recommended size and love it. It was a few hundred dollars more but well worth it.

Great tip. Could I ask what make and model you did install?

 

[Arc]

Update. I just launched and got all systems up and running. My first impression is the new stern thruster did not do as well as I had hoped . It moved the boat but cavitation a bit and didn’t have much bite. I had empty tanks and no gear on board. So the waterline was high. After loading up it stopped cavitation and moved nicely. The big surprise was using bow and stern at the same time. I can now do 360’s in place . That’s a great achievement for a deep draft Downeaster. I’m happy.

 

[Comodave]

It is a Sidepower SE100/185T 8hp unit. We were on a side tie with winds blowing us onto the dock of about 25 to 30mph. One of the fenders rolled out of place. I pushed as hard as I could and didn’t move the boat even 1/4”. Turned around and put my back into it using my legs to push, nothing. Then I thought about the thruster. Had my wife activate it and the boat immediately moved off the dock and I was able to put the fender back in place. We love the thruster. I would like to put a bow thruster in but the water tanks are in the way. I expect that I will eventually put an Exturn bow thruster in the boat. We have twin engines but I have to maneuver the boat from the flybridge and by the time I get down to handle the stern line the boat usually has blown off the dock. With the wireless remote I can just bump the thruster and we are back on the dock.

 

[Newtrawlerowner]

Update. I just launched and got all systems up and running. My first impression is the new stern thruster did not do as well as I had hoped . It moved the boat but cavitation a bit and didn’t have much bite. I had empty tanks and no gear on board. So the waterline was high. After loading up it stopped cavitation and moved nicely. The big surprise was using bow and stern at the same time. I can now do 360’s in place . That’s a great achievement for a deep draft Downeaster. I’m happy.

There is an additional thruster cowling that can be installed to prevent or minimize cavitation.

 

[Comodave]

I thought that our boat might need the shallow draft cowlings but when we launched it, it worked so well without them that I gave up on the idea. But they may help in your application. Easy enough to install them.

 

[Arc]

I have them installed already. The problem with a Downeaster is the stern is flat and shallow. I only had 10” under the waterline at center. After I loaded I was fine . The 2” more of draft was enough to stop the cavitation. I never run light so I’m good.

 

[Comodave]

Sounds like the plan is to keep everything loaded and you are good to go. I don’t remember exactly how much I have below the waterline but it was more than Sidepower said I needed.

 

[Hinckley2019]

I have the MS400 single with bow and stern thrusters and find them both useful. In a light wind it's not hard to back in and with the stern thrusters to control the boat within inches.


And a stern thruster is relatively cheap to add, with a lot of benefits.

Hi...I am interested in adding a stern thruster to my MS 400 single. Could you please advise which brand and model stern thruster you have on your boat. And are you setup to operate at 12V or 24V? Do you have a dedicated battery or batteries for each thruster, if yes, where did you have them located. If you have any information on price that would be helpful too.
Thanks-

 

[Hinckley2019]

The worst mistake in installing a thruster is to go too small. A larger thruster will work much better and have to run for shorter times. The cost differential is relatively small. I put a stern thruster on my boat and went one size larger than the recommended size and love it. It was a few hundred dollars more but well worth it.

Hi could you please share the brand and model stern thruster you installed on your boat. If you can provide cost that would be helpful information too. Did you have your stern thruster setup on 12v or 24v and is the battery dedicated to just the thruster. Thank you-

 

[Comodave]

I put a Side Power 8 hp unit in my boat. It is a 12 volt system. I put a dedicated Optima AGM battery next to it. It has its own 15 amp Promariner charger for that battery. It took me 2 days to install it after some advanced planning. The total cost was around $4500. But I did all the labor. It was a simple thing to do. I measured a bunch of times and cut the 8” hole once. Then it was just bolting it together and wiring it up. There was a bit of fiberglass work, support fot the horizontal motor, glassing in a plywood shelf for the battery and a bit of epoxy work on the transom due to the camber of the transom. Maybe the hardest part was running the control wiring to the flybridge.

 

[Seevee]

Hi...I am interested in adding a stern thruster to my MS 400 single. Could you please advise which brand and model stern thruster you have on your boat. And are you setup to operate at 12V or 24V? Do you have a dedicated battery or batteries for each thruster, if yes, where did you have them located. If you have any information on price that would be helpful too.
Thanks-

Hinckley,


I've got a Side Power SP 95T (both bow and stern), 7” dia, 10 hp 400A, 12v. No dedicated battery, just uses house bank. And I like that because I have 6 batteries (6v) that will power it rather than one or two.



I could make an argument for a 24 unit with two dedicated batteries.


The above unit moves the stern ok... not superb, but hard to move a stern regardless. Works great for the bow.


Both thrusters and valuable tools to have, on my single engine MS 400.