Bow thruster Impeller/Prop stuck

[quovadis]

Hi Just got over from Aus to get the boat back to running order.  Spending a fortune on the upkeep after 3 years of idleness.  Just replaced the dead bow thruster battery and all I get is a click when engaging it.  Opened up the weed hatch and put my hand down onto the prop.  It is stuck.  If I remember correctly the prop used to rotate freely, Should the propeller be stuck as engaged or rotate freely?

 

[ditchcrawler]

1 minute ago, quovadis said:

Hi Just got over from Aus to get the boat back to running order.  Spending a fortune on the upkeep after 3 years of idleness.  Just replaced the dead bow thruster battery and all I get is a click when engaging it.  Opened up the weed hatch and put my hand down onto the prop.  It is stuck.  If I remember correctly the prop used to rotate freely, Should the propeller be stuck as engaged or rotate freely?

 

They are normally driven via a bevel gear box so you are trying to turn the motor as well at what ever gear ratio the bevels are. When it happened to me I put a pair of grips on the motor shaft  which broke it free,

[quovadis]

Thanks let me understand.  when not in use should the propeller run free?

If it is stuck is the engaging mechanism still engaged?

There is a click. Now I know on the farm we used to tap the stater motor on the tractors to help them along, is the click indicating the thing is stuck or a power issue?

 

[ditchcrawler]

The gearbox is constantly engaged so if the prop turns so does the motor. I don't know the ratios of your box so have no idea how hard it would be to turn the motor with the prop, but you should be able to turn both motor and prop with the motor shaft between the motor and the bit in the tube. If you cant something is seized up. If you can its probably an electrical problem. Don't give it a gentle tap with a hammer or anything else.

[quovadis]

Thanks this is really helpful.  Ok no tapping!  It is a Vetus Bowthruster, does that help with the ratio and should I be able to turn it.

A few years ago I had ir serviced.  The mechanic took the motor out while it was in the water.  I cant remember how he sealed it as the motor attachment (Allan key screws) is lower than the water line.  Any idea how I can remove the motor and not flood the thruster bay.\?

 

[cuthound]

Check that it is not the motor seized by removing it from the gearbox and seeing if it will turn.. Mine sized because the condensation in the BT compartment caused the armature to rust and stick.

 

I was quoted £1200 for a new motor, but got Cox Auto Electrics in Atherstone to refurbish the motor for about 1/3 of the cost.

[blackrose]

Before you do take the motor off, check the brushes. Remove each brush but note which brush came from which holder and which way around they are so that they go back in the same way if they're still ok.

 

Vacuum any carbon dust from the brush holders. I think there's a minimum brush length (which I don't have) before they're considered worn out. 

 

Whether you end up using the same brushes or replacements, squirt a bit of WD-40 into each brush holder before putting the brushes back in. 

39 minutes ago, quovadis said:

Thanks this is really helpful.  Ok no tapping!  It is a Vetus Bowthruster, does that help with the ratio and should I be able to turn it.

A few years ago I had ir serviced.  The mechanic took the motor out while it was in the water.  I cant remember how he sealed it as the motor attachment (Allan key screws) is lower than the water line.  Any idea how I can remove the motor and not flood the thruster bay.\?

 

 

The motor is on a mounting not directly attached to the BT tunnel. You can safely take the motor off the mounting without flooding the boat. Just don't take the mounting off the tunnel. 

[quovadis]

Thank you.  Just spoke to a most helpful engineer who advises that when removing the motor I must be careful with the Spline gear (I think he said this) as it needs to go back the same way.  Im going to have a go but will probably end up blowing something.

[ditchcrawler]

48 minutes ago, blackrose said:

Before you do take the motor off, check the brushes. Remove each brush but note which brush came from which holder and which way around they are so that they go back in the same way if they're still ok.

 

Vacuum any carbon dust from the brush holders. I think there's a minimum brush length (which I don't have) before they're considered worn out. 

 

Whether you end up using the same brushes or replacements, squirt a bit of WD-40 into each brush holder before putting the brushes back in. 

 

The motor is on a mounting not directly attached to the BT tunnel. You can safely take the motor off the mounting without flooding the boat. Just don't take the mounting off the tunnel. 

Mine is a Craan and I can get to the shaft between the motor and the leg to turn it 

[Momac]

Sounds like an electrical issue such as isolator switch or solenoid faulty or corroded electrical connections ?

 

 

[MtB]

Seeing as no-one else has suggested it, my suggestion is abandon the BT and learn to steer without it! 

 

Proper boaters don't need bow thrusters 

 

Apparently!

[Momac]

12 minutes ago, MtB said:

Seeing as no-one else has suggested it, my suggestion is abandon the BT and learn to steer without it! 

 

Proper boaters don't need bow thrusters 

 

Apparently!

Some folks think proper boaters don't need engines

 

[ditchcrawler]

17 minutes ago, MartynG said:

Some folks think proper boaters don't need engines

 

Or electricity or toilets

[MtB]

18 minutes ago, MartynG said:

Some folks think proper boaters don't need engines

 

 

Oars!

[Momac]

1 minute ago, MtB said:

 

Oars!

Sails

3 minutes ago, ditchcrawler said:

Or electricity or toilets

I wouldn't go that far

[Alan de Enfield]

42 minutes ago, MtB said:

 

Oars!

 

Apparently they used to gather round all the ports when the sailors were due in.

[quovadis]

Progress today.  Cleared the work space this morning, took out battery and removed other wiring.  Off on my bicycle to Screwfix for a hex bit set,  needed the 6mm Hex socket. Removed the solenoid cover and the control wire and then unscrewed the 4 hex screws.  Lifted (struggled a bit, I'm not as young as I used to be).  off she came.  A service  being needed, I took her via my trolley to, DBJ Auto Electricians in Uxbridge.  Run by two elderly gentlemen who can rebuild any motor.  They work in an overall but are dressed in collar and Tie.  Delightful gentlemen and a pleasure to deal with in their old and cluttered shop.  The refurbishment is going to be between GBP300 and GBP400, so I'm saving my pennies.

[quovadis]

22 hours ago, MtB said:

Seeing as no-one else has suggested it, my suggestion is abandon the BT and learn to steer without it! 

 

Proper boaters don't need bow thrusters 

 

Apparently!

I confess and plead guilty to not being a proper boater, more of a fair weather rookie from down under, even though we brought her down from Cheshire without incident (oh no my wife fell in the pound on number 18 of the Wolverhampton 21 and was rescued by 2 huge,  I think polish guys who came from nowhere.  This was in March at about 20:00 hrs FREEZING and dark.  I'm sure this was reported in the Wolverhampton Mail (amazing scene on the 21 as woman was caught stripping off on the deck so all her wet clothes and thick coat stayed outside before her hot shower.))  

[blackrose]

Ok. I'd be interested in what they find. I hope you're not going to be charged 3 or 4 hundred quid if it was just a set of new brushes. I know vetus brushes are expensive, but you can find much cheaper alternatives. 

[quovadis]

I have dealt with these guys before.  A mechanic replaced an alternator for me.  I did not think it was faulty, took it to them and they put it on the test bed for GBP10-00.  I now have a spare alternator.  When I say  the BT need a service I'm being kind, its seized solid, I tried to remove brushes but could not.  The boat has been sitting for 3 years  due to no covid travel.  So I'm getting her back to "ship shape", just fitted an extra 12 anodes, 2 pack resin hull coating, new leisure and BT battery, funny the starter battery is fine.  New PRM gear box by Alex Fowler from Nantwich, brilliant mechanic.  The moral of the story, especially the BT, "Use it or loose it".

16 minutes ago, blackrose said:

Ok. I'd be interested in what they find. I hope you're not going to be charged 3 or 4 hundred quid if it was just a set of new brushes. I know vetus brushes are expensive, but you can find much cheaper alternatives. 

Will report the damage once I know

[Momac]

14 minutes ago, quovadis said:

  The moral of the story, especially the BT, "Use it or loose it".

 

That's correct.

With a  few  exceptions things  on boats  rarely wear out - but they can certainly rot due to lack of use.