Bow thruster weak

[jcwads]

Hi All, bow thruster cut out the other day, prob over used it as was holding to a choppy quay...

But now it’s really weak when operating it! Any ideas what it is?

 

[Elessar]

Hi All, bow thruster cut out the other day, prob over used it as was holding to a choppy quay...

But now it’s really weak when operating it! Any ideas what it is?

If it happened suddenly, you either killed the battery or injested a bag or similar. Jump in the water and stick your hand in there. There will be sharp barnacles in there so take care.

 

[jrudge]

My t40 has this and Essex changed the bow thruster motor ( can be done in water ) which solved it.

I had previously checked connections inc the 12v high current panel and also operated with the battery transfer switch on. Neither worked. Motor is very very heavy !

 

[MapisM]

prob over used it as was holding to a choppy quay...

I can't think of any other reasons on top of those already mentioned, but I'd suggest you to avoid using it for such purpose, once fixed.
No "normal" b/t installed on a pleasure boat can withstand continuous usage.

 

[jcwads]

I can't think of any other reasons on top of those already mentioned, but I'd suggest you to avoid using it for such purpose, once fixed.
No "normal" b/t installed on a pleasure boat can withstand continuous usage.

Yeah I get that, guilty as charged. I don’t normally use it like that but was on St Mary’s quay on the Scillies and paranoid with my nieces and nephews clambering aboard and the bow wasn’t fendered appropriately

 

[Elessar]

Yeah I get that, guilty as charged. I don’t normally use it like that but was on St Mary’s quay on the Scillies and paranoid with my nieces and nephews clambering aboard and the bow wasn’t fendered appropriately

Yes but continuous use doesn’t break it - they have a thermal cut out to protect themselves. They come back on line when cool.
Frequent continuous use is another matter.....,

 

[Momac]

Condition of solenoid switch is important. If contacts carrying high current are burned the thruster power can be impaired.

 

[kashurst]

Unless really keen to jump in the water, measure the voltage at the bow thruster motor, with it off and with it operating. If it drops below 12V when running its probably the battery or a connection along the way. I melted a battery cut out switch on my bow thruster battery last year after a particularly long use of the thruster. Didn't fail immediately, just slowly died.

 

[jcwads]

Unless really keen to jump in the water, measure the voltage at the bow thruster motor, with it off and with it operating. If it drops below 12V when running its probably the battery or a connection along the way. I melted a battery cut out switch on my bow thruster battery last year after a particularly long use of the thruster. Didn't fail immediately, just slowly died.

Nothing clogging the prop as checked it. Volts cut way below 12 when operating it. Anyone know where to look for a fix without it being a new motor!!’

 

[Elessar]

Nothing clogging the prop as checked it. Volts cut way below 12 when operating it. Anyone know where to look for a fix without it being a new motor!!’

Measure volts at battery when operating then volts at motor when operating. They should be the same or very similar. If not you have a burned solenoid, or a loose joint or similar.
If they are the same get a known good battery and put that in. See if you still get the voltage drop.
I’ll be really very surprised if it’s the motor.

 

[jcwads]

Measure volts at battery when operating then volts at motor when operating. They should be the same or very similar. If not you have a burned solenoid, or a loose joint or similar.
If they are the same get a known good battery and put that in. See if you still get the voltage drop.
I’ll be really very surprised if it’s the motor.

Mark, assuming bow thruster works off my domestic battery in engine bay?

 

[Elessar]

Mark, assuming bow thruster works off my domestic battery in engine bay?

I don’t know but again I’d be surprised I expect a battery in the bow as it saves money on very heavy cabling.
Other T40 owners need to chip it it’s bound to be a standard fit.
So the low voltage you have observed is at the motor?
You certainly need to know which battery feeds it to figure this out.

Has your owners manual got a wiring diagram?

 

[jimmy_the_builder]

No remote bowthruster battery on the T40.

 

[jrudge]

There is not a dedicated battery.

I don’t know for sure which it is but I had battery issues on mine and pushing the crossover botton solved it ( for that manouvre ) so push it and see.

Volt drop next to things like that is I believe normal. My winch works fine. It if you measure the volts at it there is a huge drop. Others may have a different view

Check connections in 24v panel ( rear cabin wardrobe I think )

My motor had gone so it is quite possibly the motor.

 

[Elessar]

No remote bowthruster battery on the T40.

Ok JW that’s definitive.

Measure at domestic batteries and measure at motor. Both when operating of course.

If they are the same/similar it’s the battery or the motor.
If they are majorly different it’s something in the wiring there will be some drop as jrudge says.

Also his idea of pressing the link switch sort of eliminates the battery.

I’ll still be surprised if it’s the motor after this incident. But narrow it down first.
If it is the motor changing it is easy it just costs ££ for the motor.

 

[jcwads]

Ok JW that’s definitive.

Measure at domestic batteries and measure at motor. Both when operating of course.

If they are the same it’s the battery or the motor.
If they are majorly different it’s something in the wiring there will be some drop as jrudge says.

Also his idea of pressing the long switch sort of eliminates the battery.

I’ll still be surprised if it’s the motor after this incident. But narrow it down first.
If it is the motor changing it is easy it just costs ££ for the motor.

Many thanks all, will look into it

 

[petem]

There is not a dedicated battery.

I don’t know for sure which it is but I had battery issues on mine and pushing the crossover botton solved it ( for that manouvre ) so push it and see.

Volt drop next to things like that is I believe normal. My winch works fine. It if you measure the volts at it there is a huge drop. Others may have a different view

Check connections in 24v panel ( rear cabin wardrobe I think )

My motor had gone so it is quite possibly the motor.

24v?

 

[jcwads]

Motor current drops significantly on use, battery stays the same. As for solenoids and knowing what to diagnose I’ve gone as far as my limited knowledge of electrics goes so I’ll have to get someone in to look at it when I return from
hols..

 

[jimmy_the_builder]

24v?

Jrudge meant 12v

 

[jimmy_the_builder]

Motor current drops significantly on use, battery stays the same. As for solenoids and knowing what to diagnose I’ve gone as far as my limited knowledge of electrics goes so I’ll have to get someone in to look at it when I return from
hols..

Do you mean voltage, rather than current? Check the connections in the 12v heavy duty box in the aft cabin wardrobe, sounds like a poor connection somewhere. In particular, it's worth checking that you're not getting a voltage drop over the isolator switch mounted in the very bottom of the box. And if you're getting a voltage drop at the bowthruster motor, check the other side of the solenoid in case it's that.