is your standard bow thruster powerfull enough

30secs is pretty quick to cut out.

You'll probably have an end cap with lots of holes drilled in it for cooling airflow - check for dust and debris accumulation in there (you'll need to remove it to check)

Do you have a remote oil reservoir? If so, check it, and check its flow (pull off the pipe at the thruster end -does oil flow? Careful, it should come out quickly!!)

Could be thruster prop fouling as previously mentioned, or a gearbox issue (overloading the motor).

Ignore battery and cable advice for the moment - that would affect performance, but not cause an overheat trip like you get.

For prolonged use, you need a hydraulic unit (100% duty cycle) but that is many £k. If you really need better performance, a bigger thruster can be fitted, but you're limited by tunnel diameter unless you want to do the £k thing again.

I think you're performance is too low for your application and there's not a lot you can do without spending. The 30sec overheat possibly can be improved though - I would expect 60secs minimum before overheat, BUT, don't forget that is cumulative. It has to cool down before you can use it again.

Move berth?

thanks for the reply you have grasped my problem 100% the thruster does not loose power or sound laboured it works well for 30 secs or so then nothing it goes from full power to nothing, whilst its working it works well nothing wrong with the performance it just will not last as long as I need it to

thanks for the advice

Jimmy

when I am down next I will look for the model no'

cheers
 
We had exactly the same problem with our 1997 Fairline Phantom 42. You could use it for a quick squirt to counter the bow swing when using engines but prolonged use over 15-20 seconds caused it to trip out.

I never really investigated it, just assumed it was down to failings in specification / installation.

Henry :)
 
I've nothing to add on the truster but would your marina allow you to install those fixed jetty fenders for some extra piece of mind?
 
I've nothing to add on the truster but would your marina allow you to install those fixed jetty fenders for some extra piece of mind?

yes already done that I have 5 of these fitted, the issue I have is the flow hits my port side and washes me into the boat I share a mooring with on my starboard side, I have loads of fenders on my boat and so does my neighbour, I have been washed against him a few times and he is fine as he knows the problems I have but it is a little embarrassing

I am going to have to go into another berth and then move my boat when the gates close or at high tide as the high tide cancels out the gates and I can get in no problem

like in one of my earlier posts I am very surprised at the thruster for cutting out so soon I never realised the problem was this bad with my sealine as the thruster never ever cut out it sometimes started to fade power wise but it did hold the bow in until swmbo could tie a rope on

just anti fouled her last weekend and the props on the thruster were clean
 
Well said. 2 props and you think you need a bigger bow thruster???
The answer is you need a better propeller that is not on the market yet , but I have seen a propeller the same size that at the same revs is 21 per cent more thrust was given on a bollard pull... its a watertrap type prop..
 
terry I have I missed something here ?????????????????????????

Hi Shaun,

Sorry for the delay in getting back to you as went out for supper.

As you are going to Cowes in the summer book a berth @ East Cowes Marina and do some berthing both on the flood and ebb tide using the local services of Tim Griffin from this parish {This is where the £150 - £250 comes in btw} who will teach you to berth properly in very strong currents without the use of a bow thruster - As Steve Dunstable would now say - I will get my coat :encouragement:

Let us know how you get on - btw plenty of photos and video will be mandatory to enable fellow forumites to view and participate in a tongue in cheek poll on how you get on ;)
 
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Two points - both following up on Jimmy's comments.

Sleipner thrusters can have a more efficient prop fitted - a significant improvement - something in the region of 30/40% I think.
You say that it is a Sleipner so give Bryn Thomas a call in their Devon distribution office - he will say if that model can be retrofitted - it would be an easy upgrade to do.

As Jimmy says, if you cant control it after 30 secs blast, I don't think it is worth extending the time it runs.
You need to investigate other methods - maybe some fixed ropes/fenders that you can "pull against" with the main engines.
I don't know what your berth looks like but I'm thinking of a permanent lines attached to pole that can easily be picked up from your crew as you reverse in.
Of course, you would need to rig it so that loose ends can't get round your props.
Just a useless comment from me - but I do think that after 30 seconds, any thruster would be working too hard to rely on.

Or a better berth
Good luck anyway
 
I have actually just stood and counted 30 seconds on my watch and whilst standing still this is quite a long time and I am now thinking my thruster does not last this long as 30 seconds was more of a guess / figure of speech, I am down for 10 days as from tomorrow so I am going to try my bow thruster and see how long it lasts

I will let you know my findings

cheers shawn
 
You need to investigate other methods - maybe some fixed ropes/fenders that you can "pull against" with the main engines.
I don't know what your berth looks like but I'm thinking of a permanent lines attached to pole that can easily be picked up from your crew as you reverse in.

Agree, we berth stern to port side and often the South Westerlies push the bow to stbd.

SWMBO steps off the swim platform onto the finger at the end with a line and cleats off to the mid hips cleat on the finger.

We then spring off/reverse to control the boat as we move back. An occasional burst of thruster is enough to stop drift.

Agree on the training in east cowes, did my day skipper training there and really good prep for dealing with strong streams
 
Might be an idea to replace the fuse. I had this once with a bow thruster. Once it started tripping it seemed to trip more easily afterwards.
Solved the problem. Also on that boat moved the bow thruster from a starter battery in the back to the main. Few metres less cable and less internal resistance in the batteries as the main had 2 big batteries in parallel. and I estimate I gained 30% more thrust. Went from weak to adequate for the job. If it does not have a dedicated battery at the front you could try a temp setup with a battery up from. The loss of voltage through the cables can be quite significant at the amps a bow thruster draws. Won't solve it tripping though.

I would test the above before spending money on upgrades. Worked for me.

Rob
 
That has *got* to be a full Lakesailor, surely...? :D:D

Wow, not heard that for a while. But well spotted!:cool:

This whole issue in a 'crazy' berth sounds pretty horrible. I'm sure there are days where you think it's just not worth the risk to go out.:ambivalence:


You mentioned the S37 was ok, but this is a lower profile, less windage boat on outdrives. So a bit unfair as the outdrives will give you a bigger swing and/or a direct pull on vectored thrust. Remembering of course that this is a tidal stream issue. Put the two together and it could become stressful.

The P40 is well specified on things like thrusters. My P38 and T40 had loads of thrust in normal use. But your berth sounds far from normal. You know what I mean when you're berthing in a breeze/current and all the the thruster will do is hold the bow but not make any progress to windward.

30 seconds is a life time on a 12V motor and heat trips are likely. Upgrading the prop does not sound good to me as surely, this will increase the loading and create a greater overheat problem, giving even less duration before tripping.

I knew It wouldn't take long for some one to make that comment :rolleyes: don't matter how many props I have you cannot make the bow move side wards in a small place in a quick time when the current is pushing the bow round to starboard only way is a bow thruster.

This sort of thread does sort of beg for it I guess.:rolleyes: I had bow and stern thrusters on my P38 but spent 1/2 a season with neither working, it sort of makes you appreciate them later. I wouldn't want to park a T40 without one though.:o

Obviously, we can't see your berth but it sounds to me like when you reverse in, the last part of the arrival is being carried out in reverse using starboard engine and BThrust to port to hold the bow up into the current. Just a shot in the dark, but do you have room to swing the boat coming in on port reverse so that the natural bow swing will assist the BThrust to port?

This berth sounds as smelly as your old loo pipes. :encouragement:

RR
 
My last boat a Fairline Sedan 36 on shafts had no bow thruster, and we got in and out of tight berths with a few additional hp used on the main engines.

Current boat Aquastar 48 has a keel and a bow and stern thruster, I was always underwhelmed by the stern thruster and considered it useless, it also sounded bike a bag of bolts, replaced the motor and now works well.

Do you have a dedicated battery next to the bow thruster or large battery cables coming all the way from your main battery bank?

You really need a large battery of adequate size alongside the thruster or the loss is too great with long cables.

You need to know, what model thruster you have , its probably a Sidepower Sleipner.

What battery ( details amps and cca) drives your thruster and how long the cables are to the thruster.

When were all the batteries last tested with an electronic battery tester, we have just bought one and it is amazing how many batteries are well below par on customers boats, a battery normally lasts only 4 to 6 years max depending on use and care.

Yes a higher thrust prop will make a considerable difference.

The joysticks fro thrusters especially on the flybridge don't last for ever, they get damp and need replacing , my fly controls were replaced at about 9 years old.

Yes talk to Sidepower/Sleipner ( same company) for advice, a good company for advice.

Also funnily enough a stern thruster would make the world of difference to berthing for fine manoevering while berthing astern.

Also don't use only fixed pontoon fenders, use these to protect the boat while berthing , then make sure you use hanging fenders preferably with socks to keep your boat off the fixed fenders/pontoon.

Fixed fenders rub on the hull and with a little dirt abrade the gel coat and wear through it very fast.

I know it hurts the pride but a day with a good tutor and practice, practice, practice makes a difference
 
Ask the manufacturer. 30 seconds seems like quite a while, but it maybe that the thermal component is out of spec and cutting out early ... or of course as someone else suggested the cooling is compromised.

Replacing the component that detects temperature will be cheap ( probably less than a £1 on ebay).

The other thing you could try is taking the floor cover off and blowing a fan on it ( assuming you have one on board). If this helps then you could add a PC type fan to the Bow Thruster power so there is some cooling when it is activated. This will probably not revolutionise things but may give you more time and cost very little.

Bear in mind that the motor is probably 4hp or so and the length of time it will run on the battery with the engine at slow revs will be finite in any event. Mine on a T40 has never cut out, but on the few occasions I have had to use if for any real length of time it will start to slow of its own accord ... so moving berth maybe less stressful. Mallorca anyone .... and bet it costs less!
 
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