Thruster Problems Fairline Targa 40

[danieleither]

I have a 2006 Fairline Targa 40. It has the original Sleipner bow thruster (fitted since new). In late 2020 I had a new Sleipner stern thruster added, along with remote controller and a new double joystick (to replace the old single one). No doubt someone will feel the need to comment this is unnecessary on a 40ft boat with outdrives, however 95% of my boating is solo and having remotely controlled bow and stern thrusters is a godsend when solo mooring, especially in windy conditions and strong tides.

The symptoms of my issue keep changing, therefore not a straight-forward description of the problem, however here is a summary of what happened:

• Having returned to my home berth, while tying off the lines the bow thruster started thrusting to starboard at full power of its own accord. My initial thought was I was inadvertently pressing a button on the remote, however I checked, and this was not the case as the remote was dangling freely from my neck. This lasted a few seconds before stopping, again of its own accord.
• After securing the boat, I powered everything down and back on again. After powering back up, at first, the stern thruster was working normally, however neither the joystick or remote control would activate the bow thruster.
• I powered down, removed the joystick from the helm to inspect the connections: no corrosion, no loose plugs. Unplugged everything, sprayed contact cleaner and plugged back in, repeating the process for connections on the remote receiver module.
• After the above, the bow thruster now worked perfectly (from joystick or remote) however nothing from stern thruster, however pushing the joystick left or right resulted in the amber light on the joystick dimming and flickering (whilst the joystick was pushed either way). Pressing the remote would not affect the amber light.
• Over the next few hours, I would power up the system and test several times, resulting in different symptoms.
• Sometimes, everything would work perfectly from the remote or joystick
• Other times, the issue would reverse from bow thruster not working to stern thruster not working, however there would always be one or the other working whilst the other wasn't.
• At one point when I powered everything up, the bow thruster decided to start thrusting continuously of its own accord, however this time at a very low power, not really enough to push the bow, but enough to create a clonking / ticking sound from the motor, juddering and making small ripples in the water (confirming it was definitely the bow thruster). Whilst this was happening, the amber light on the joystick was flickering as well. It would continue to do this until I powered down from the breakers. Turning the remote control and joystick off did not stop this happening. Also, whilst this was happening, pushing the joystick to the left or right would momentarily stop the thruster juddering for a second or so, before it then started up again.
• Eventually after several hours, everything was working normal again every time I tested.

Fast forward to the next day, I powered everything up to test again before leaving the boat, and the problem was back (bow thruster working but nothing from stern thruster).

Some videos here to demonstrate some of the symptoms:

Bow thruster motor juddering of own accord

Bow thruster motor juddering, operation of joystick stops juddering momentarily

Stern thruster working, bow thruster NOT working

Bow thruster working, stern thruster NOT working

I contacted the installer who sent a Sleipner-qualified engineer. Before inspecting, they suggested it is probably to do with the solenoid on the bow thruster which can get stuck and cause problems like this. As the symptoms keep changing, I was sceptical of this. Whilst I'm not an expert or marine engineer, the fact that the symptoms kept changing suggested to me an electronics failure as opposed to mechanical, and my thought was it could be the remote module failing (as this can ultimately produce signals which can influence operation of both the bow & stern thrusters, AND contains electronics / circuitry). Anyhow, they came out to inspect and on arrival to the boat everything was working normally and they've stated they are "unable to find anything wrong with the system". This was around 2 weeks after the faults occurred, and the boat hasn't been used inbetween. They did inform me that the engineer had noticed some water / liquid in the engine bay, near to the bow-thruster emergency stop button and suggested this could have caused some problems if it had got wet.

Right now, everything is working properly again however I feel the likelihood of this happening again is high, and therefore I have little confidence to take the boat out.

Has anyone experienced anything similar or can point me in the right direction as to what could have caused this? If it's possible to determine what 'could' be causing this by process of elimination, I'd rather spend some money and replace it than risk colliding with other people's boats.

 

[colhel]

Battery perhaps? When everything worked fine after 2 weeks, we're the batteries on charge?

 

[PowerYachtBlog]

A friend of mine had a similar issue on a QL bow thruster some years ago. Going to starboard when switched on. It was a blocked relay if I remember well.
It is something quite common with QL bow thrusters I have found out.

 

[GaryJeffery]

Hi I concur with the relay possibility, had an issue with similar erratic behaviour and turned out the relay was the problem, swapped for a new one and all good again. On inspecting the old one I could see the faces of the high current contact were bad, caused by a little wear and carbon buildup from the arcing of use. As an experiment cleaned them up with some fine wet n dry and popped it back in. It worked just fine again, still good 2 years on!
Basically not enough current able to flow through the relay. Should it ever happen again I’ve got the spare which can be swapped in a few secs.

 

[dj43]

We had similar issue with our new side power thruster, came on continuously just as we were holding station for a bridge lift, went off a few minutes later after we had crabbed through bridge opening, on mooring up came on again, not a nice experience
Turned out water had got onto the contacts of the thruster motor , a remote set of contacts were fitted , I also made sure no more water could get to the motor ,never happened again that was ten years ago.

 

[Fire99]

Since you have a new controller, is it possible to temporarily reconnect the old (bow thruster only) controller to the Box thruster and see it returns to working normally? I'm not familiar with the system so I don't know if the Stern Thruster operates on entirely separate electronics etc but just shares the double controller joystick or if it is integrated with the system but if the bow thruster has been working A1 ok prior to the stern thruster / dual joystick being installed, I'd find it highly unlikely the issues relate to generic issues (water near stop switches, failed relays etc). It's possible but I'd always start with what's changed first.

 

[Momac]

My QL bow thruster started up after heavy rain with the helm exposed . You would think the switch would be waterproof but it seems not.
I am since then careful to switch off the power when the bow thruster is not required.

 

[danieleither]

My QL bow thruster started up after heavy rain with the helm exposed . You would think the switch would be waterproof but it seems not.
I am since then careful to switch off the power when the bow thruster is not required.

Oh wow - yes everything on the helm should be splashproof. I've been caught out in rough conditions several times, water splashing over the helm is not uncommon.