Long or short shaft?

C

cngarrod

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Having just purchased my first boat (a small single engined cruiser) which will only be used for river and coastal trips. I wish to add the peace of mind that a secondary outbaord will bring. The boat has a Volvo petrol inboard and i have been advised that a 4 or 5 Hp engine should do the trick. But upon looking around there are long shaft versions.. what's the best to go for?

Yours,

Still green on the experiences of boating!
 
I think that 4-5 hp is a bit on the light side for your boat, particularly if you happen to be running against a current. I would go for a 10hp longshaft. The longshaft allows the bracket for your auxiliary to be mounted higher up the transom and makes for easier access. If you can get and electric start motor so much the better.

It is many years since I had a boat with an auxiliary outboard - the last one was a Shetland 570 - 19ft cabin cruiser. Problems to think about are

a) How do you operate said motor and also see where you are going - not easy if you are hanging over the transom. In my own case I solved this by having a home made extension tiller. This was a length of white PVC pipe of the sort used for domestic sink waste. Cut two slots length wise diametrically opposite each other. The pipe was then slid over the twist grip throttle on the engine and clamped on with suitably sized jubilee clips. This allowed me to stand in the cockpit and steer/adjust speed while still being able to see through the windscreen.

b) How do you start it - electric is best but if you have a manual start, make sure you install it in such a way as to have enough room to pull the starter cord.

c) You have to have enough room to tilt/lower the beast. Again this just needs a bit of thought when installing it. Alternatively you can buy brackets which raise/lower, allowing the engine to remain in the lowered position

d) Re installation - make sure the area of transom you intend to use is strong enough. This probably will not be a problem but you should mount the bracket on a wooden pad to spread the load a bit.

e) Think about where to store fuel for the outboard as odd cans of petrol about the boat are not ideal. It is also worth investing in a plastic fuel can as the metal ones invariably rust around the bottom rim and leave nice marks all over the boat and up your trouser leg when you are carrying the fuel can.

You are absolutely right, however, an auxiliary does give peace of mind. Make sure you practice using it as given its offset position you will find the boat will turn better in one direction than the other.

Nick
 
Thanks Nick, good advice especially about the doctored extension! There is already an auxillary bracket on the back, starboard side which shouod be ok, it has the load sharing wood on it to! I will probably purchase a plastic fuel tank and store it in one of the holds at the back of the boat, worst case scenario woudl be that it needs to get me to a local marina of which there are several near where i cruise.

Once on board and in the river, i will practice using it and the engagement of it so i am more capable and confident!

But then i am still getting used to boating in general!

Out of interest if you started with a Shetland 570, what do you have now.. and what did you have in between?

Craig.
 
Re: Boating History

I have been boating most of my life and as a boy, my folks had a holiday home on Millport on the Clyde. I had a summer job there running the hired rowing boats and small motor boats. I also took the fishing parties out at night - a 12 year old in charge of a boat with 40+ fishermen aboard - the health and safety people would die nowadays.

My first boat in 1980 was a Dowty Turbocraft speedboat which I stripped back to bare hull and rebuilt.

That got traded against a fairly old and tired Shetland 570 which I also renovated - ended up with a 140hp Yamaha on her which could pull 40knts but made your teeth rattle. I also had a 10hp longshaft Evinrude auxiliary which got used for real once or twice. It would drive the Shetland to about 8/9 knts. A really capable little sea boat the Shetland.

I then had a Fairline Mirage with twin 125hp outdrives. I grew to hate outdrives and would not have another one. That was a nice boat and got my wife involved but whilst she was safe enough at sea, she would slam in any ripple (the boat that is!).

Now I have a Birchwood TS33 which is a flybridge boat with twin 200hp diesels on shafts. I have had her for 10 years and have been really happy with her but she is for sale at the moment as the she is getting a little long in the tooth. This is a brilliant sea boat and has coped with very big seas and always brought us home. She has also been well screwed together.

I don't know what I will do next - I'll get the money then look around. I might consider a motor sailer but I know nothing about sailing.

Nick
 
Re: Boating History

Wow! that is some serious experience!

My plan is not to dissimilar except i am about 30 years late in starting by comparison! I would like to learn and play with this one and then move up to a bigger one next year (funds permitting!) and see what i have got from there... the only problem i can see is that i will always rather be on the boat and not in the office... which is what pays for the boat... i need the 6 numbers.. and soon!

Cheers Nick,

Craig.
 
Re: PS

Sorry, I meant to say that if you have an existing bracket, that will determine whether you need a longshaft or shortshaft engine. Measure the distance from the top of your bracket to the water line (try to do this alongside with you on the pontoon and not on the boat). Shortshaft engines generally have about 15/16" from the top of the bracket to the water. Longshafts come in two sizes - 20" and 25".

Usually there are plenty of decent second hand motors about and you do not need to pay new prices for an auxiliary.

Good luck

Nick
 
Re: PS

You did'nt tell me it was a retracting bracket but yes, with the bracket down.

Nick
 
Re: PS

Nick, have found an 18hp outboard for about a ton.. do you think this will be too heavy? as i am concious that all the weight is at the back of the boat... any thoughts?

ALso, should the bilge pump be on all the time or every now and then?

Cheers,
C
 
Re: PS

An 18 horse might be a bit heavy for your bracket. If you can, ask the seller if you can try it on the bracket and then see how easy it is to raise and lower. Also look out for any sign at all of flexing of the transom. Bear in mind that there is quite a load on the bracket and you don't want it pulling out of your nice Fibreglass transom. The other thing to remember about anything dangling off the back of the boat e.g. engine on a bracket or a dinghy on davits is that the mounting (bracket/davit whatever) has to be able to carry at least three times the static weight imposed on it. This is because when you go over waves, the load is being bounced up and down on it so its not like a static load you might get on dry land. May be not so much of a problem on the river as at sea but even there you will get the wash off other boats, etc.

To illustrate, imagine sweeping the wife off her feet and carrying her in your arms. OK so far so good! Now try jumping up and down and see how long you can keep her up!
I rest my case!

Incidentally, if you go for that engine its a bit too big to rely purely on the clamps. You should also bolt it onto the bracket using stainless steel nuts, locking washers & bolts. Also buy one of these outboard locks for security. They basically fit over the clamps and are padlocked in place. Of course we have no need for such devices in Scotland but you live in England!

Re your bilge pump, first off, for safety you should have a manual pump as well as an electric pump. I would be surprised if Fairline had not fitted one. Usually they have a detachable plug in pumping handle.

As far as the electric one goes, the best plan is to have it attached to a float switch so that if the water rises above a certain level, it automatically comes on. There should also be an override switch to bring it on irrespective of the float switch + the whole arrangement should be capable of being switched off altogether, again irrespective of float switch. There should also be a warning either audible or a light to tell you the pump is operating. You might hear the pump when moored but there is no chance when the engine is running

I always left my automatic bilge pump on (i.e. it comes on when the float switch tells it to) when in the marina as there are always drips at the stern glands on shaft drive boats. Sterndrives should really be more or less dry and if you've got enough water in to need the bilge pump something ain't right, probably the seal between the hull and outdrive. Minor leaks here can be sorted out with silicon sealer but this needs a lift out the water. Another source can be rainwater and you should check your canvas/self draining arrangements to sort that out. Cockpit drains regularly become fouled with leaves and other crap.

OK so all of this means that you only have your bilge pump actually running when it is needed but, whilst underway, if you have a float switch, have it set to operate automatically. As to leaving it on automatic when the boat is unattended, if you have shorepower then fine, if not, you might occasionally return to the boat to find a flat battery. On the other hand, that might be better than water up to the engine sump! You takes your choices!

Where are you based? I am in London pretty regularly and available for an evening boat handling lesson or two in exchange for a small libation.

Nick
 
Re: PS

I think i will leave the 18hp engine.. the guy said he would struggle to lift it himself, so perching it on the back of my bracket and transom would be a bit too much!

I think from original the boat didn't have a bilge pump, as having just got a copy of the invoice the electric was a costed option (£30). I am going to purchase a manual one this weekend, but probably not a fixed unit, as i can place it where i want it then!

We have had some very heavy rain down here of late and having checked the boat there is only a bit of water coming in from the window rubbers at the cockpit... will sort it out for real over the winter, but will apply some silicone for now.

The Bilge did get a bit of water in last weekend when we went out, but i think that might be more down to weight than anything, ther were 7 on board... so it was quite heavy!

How easy is a float switch to fit? or is it easier to get one on a new pump?

As for my location, i live in Ipswich (where the boat is too!) which is about 70 miles from london.. maybe a bit too far.. (although only an hour on the train?) however i am in london at least once if nto twice each week, so maybe a get together might not be a bad idea! although the boat will have to stay put unless you come to me!

As for the sweeping the mrs off her feet.. not sure how.. but you must have met the wife at some point.. jumping up and down.. i don't think so!

One other question, how do i check to see if the depth sounder is working correctly.. i don't want to get caught out! Is it likely to be in metres or feet do you think?

There is a speedo fitted, unless it is connected to the rev counter, i cannot see how it would measure the speed?

I look forward to the beer!

Cheers,

Craig.
 
Re: PS

OK dealing with the various questions

a) Don't get a non fixed manual pump. They are really only suitable for dinghies. A fixed one is relatively easy to install and will shift a lot more water. If you need a bilge pump in an emergency you do not want to be pfaffing about with loose tubes etc., etc. Cost about £40.

b) If you already have an electric bilge pump, just buy a float switch and wire it in. If you don't know how let me know and I will send a sketch of what to do. If you have just got a simple on/off switch at the moment, you might want to change that or alternatively make that the "master" with another switch to override the float switch. Also you want a warning light somewhere. You can buy a bilge pump switch unit complete with three way switch and warning light - about £25. Float switch circa £20-25
If you want a new electric pump it is possible to buy units with a float switch built in but that would are more expensive option, maybe £50 + you still need the switch

Generally all these options are pretty easy to install, depending on access to the bilges/wiring loom

c) The speedo (we boaty people call it the Log as a decent one also logs the distance travelled) could be one of two types. The cheapo operates by being connected via a clear plastic tube to a device which looks a bit like a pen hung at the bottom of the transom on a small plastic bracket. This provides a vacuum which operates the speedo - they are very unreliable and frankly not worth fixing. If you have a small plastic bracket but nothing projecting from it this is what you probably had and the fitting has long since disappeared (as they do)
More likely you have a proper log which is operate by an impeller. This is a little sort of paddle wheel which projects under the hull via a skin fitting. As the boat moves through the water it spins and produces an electrical output which drives the speedo. These can become clogged and stuck so that they do not spin. They are usually in a sort of tube (viewed from the inside of the hull) which has a removeable top and a blanking plug. This allows you to withdraw the impeller and stop the inrush of water with the plug while you sort out the impeller. Me - I have always done anything like this with the boat out of the water but it can be done whilst in the water.

I am not aware of any boat type speedo which literally has some form of mechanical drive so thats probably why you can't find one on your boat!

Re calibrating the sounder, it depends on the make what is displayed (or indeed how it is displayed) but the easiest way to check it is, whilst moored or somewhere with some depth under the boat, weight a piece of string and lower it over the side until you feel the bottom. Then measure how much it took and compare with sounder reading. If it requires adjustment, refer to the manual if you have one.

The weight carried by the boat should not really affect her water tightness. Try running with the engine covers off and see if you can identify where the water is coming from. It could, for example be from the raw water side of the engine cooling system or it may be from around the transom area at the sterndrive mounting.

Just one more thing. Seven on a 19 footer is just about OK on the river but overloaded if you go to sea. Just watch for that. Also with 140hp, your boat should be pretty quick and you want to actually open her out now and again to avoid glazing to the bores, etc. It will also let you see how your engine is actually performing. If you get the chance, take her out in settled weather once you've got your auxiliary sorted out and give her a bit of a blast to see what happens. Keep your eye on the gauges, especially the temperature gauge and if it rises unduly slow up and return to port.

Next time I am overnighting in London I'll let you know

Nick
 
Re: PS

Cheers Nick,

Helpful advice... there are lots of small things that need doing on the boat, one of the reasons as to why i purchased an old model for little money... as it means i can play and learn.

I see the point about the manual bilge pump, i will fit one but retain a movable one just in case i get water in other areas.. unlikley but for a few quid it won't hurt.

Will take the boat out and see where the water is coming in from, a mate of mine is a mechanic and knows quite a bit about engines... i know the marine version is a bit different, but will see and make sure that all is moving where it should and nothing is coming out from where it shouldn't!

Will investigate a float switch, but any tips or diagrams you have may be handy... alothough a bit of logic might do the trick also!

The boat is quite quick, but bearing in mind i have only done river work so far, i can't open her up for too long... too much traffic around and not legal!

Should i have 100% chain on my anchor.. as the previous owner had about 3 foot of chain and the rest was rope... but i have no specific cleet to join chain to... so am unsure if it should use a combination or just chain...?

Thanks for all your help, look forward to meeting up at some point - mind you am on holiday from monday for 2 weeks... so it will have to be after then!

Cheers,

C
 
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