R21 EC Bowthruster Not Working

[Graceland]

Hello fellow Tugnuts,

I’m a very happy owner of a 2013 R21 EC. It’s in extremely good condition, and my wife and I pride ourselves on keeping our boat in ship shape.

My question has to do with the bowthruster. We use it very infrequently, but it’s definitely a feature we love having for tough docking situations. The bowthruster was working perfectly earlier in the season, but yesterday we turned it on and the light on the joystick lit up, but nothing happens. We checked the fuse, and it seems fine. We replaced both batteries at the beginning of the summer.

So, we’re stumped. Has this happened to any of you guys who own a R21 EC?

Any help appreciated!

Thanks so much.

 

[Capt’nKarl]

As a previous owner of a R-23EC with bow thruster issues here’s where I’d start now that I know what to do. If the fuses are good then it’s likely a voltage issue or issues with the brushes in the motor. Check all connections first and make sure they are tight. If this fails to get power to the bow thruster then turn off the battery switch to the thruster and connect jumper cables ( it might take 2 sets) from a good battery directly FIRST to the negative side of the battery and then to the negative motor connection and then connect the positive side to the battery. Keep the other positive lead from touching anything and then touch the positive lead to the positive motor connection. You’ll hear the motor start immediately unless there’s an issue with the brushes in the bow thruster motor. You can remove the motor easily and inspect and clean the brushes. The brushes were my issue. Hope this helps.
Karl

 

[Graceland]

Many thanks for your quick reply. I'll give it a shot.

It's really an odd situation. When I try to use the bowthruster literally nothing happens (no sound at all from the thruster motor). It was working fine just a few weeks ago.

I can't imagine it's a voltage issue with 2 brand new batteries installed this year, but I guess you never know.

At any rate, I really appreciate your insight.

Best,

Gregg

 

[knotflying]

Sometimes the fuses may look good, but they are not. Turn off the thruster switch and then take an ohm meter and do a continuity test. I prefer to use the buzzer sound to determine a closed circuit. Place one probe on each terminal on either side of the fuse. If the fuse is good then the buzzer sound should come on. If that proves that the fuse is good, as stated, make sure all connections are good and thruster battery is in good condition. I would suggest going on the Imtra/sidepower website and follow their troubleshooting guide after you have exhausted the tests and checks mentioned.

 

[Graceland]

Good suggestion - I think I will replace the thruster fuse next. I tried jumping the batteries this morning and it did not have any effect on the thruster. Batteries appear to be fine.

 

[gsc3]

I had a problem with the bow thruster on our 2016 C24 not working. It turned out to be corrosion in the thruster's motor. See my post "Repair of Lewmar Thruster 110TT on 2016 Cutwater 24" post by gsc3 on Thu Oct 22, 2020 5:37 pm. Maybe your thruster problem is similar. Good luck! . . . Slade Cargill

 

[bob daily]

Mr.Gregg there is a good trouble shooting guide in the back of the manual for the side-power thruster system. (Installation and user's manual) if you don't have one, PM me and I will send copy of mine.
Also you can contact Intra Corporation at (508) 995-700 or side-power@intra.com
Hope that helps. Bob

 

[Capt’nKarl]

If you connected 12 volts directly to the bow thruster motor and didn’t get a response Its probably the brushes in the motor housing. That’s exactly what happened when my thruster quit working. It’s not too difficult to remove the motor and access the brushes. Hope you get things working.
Karl

 

[Graceland]

Capt'n Karl - This may be a dumb question, but do I have to take the boat out of the water before I open the thruster to replace the brushes? Boat basically stays docked in the water from May to October, with the trailer stored off site during that time. I could make the trip to get the trailer and then take the boat out, but it would be a further hassle in this saga.

Thanks,

Gregg

 

[Capt’nKarl]

Gregg. No problem. You can remove the bow thruster motor while the boat is in the water. Once you remove the battery cables and the housing you’ll see the mounting bolts. Once you remove those bolts the motor will lift out and you can remove the brushes. There’s a notch in the motor that matches the shear pin in the gear housing that need to line up when you reinstall the motor. Once you’ve cleaned and replaced the brushes test the motor before you reinstall it to make sure it runs. I put a little marine grease on the rotor housing and shear pin area as well. Hope this helps.
Karl

 

[Graceland]

Good morning, Kaptain Karl

We had our R21-EC fully serviced before putting her back in the water this season. Turned out the malfunctioning bow thruster issue had to do with a bad “heat relay switch”, or something to that effect. (Didn’t know know the bow thruster even had such a thing.)

Anyhow, $200 including labor and we’re back in business!

Just wanted to circle back and let you know it was resolved (and what the diagnosis turned out to be).

Best,

Gregg