Tips on removing an inboard

dylanwinter

dylanwinter

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www.keepturningleft.co.uk
I think that I have got my head around the maths of getting the lip of the so far theoretical outboard well at the right height

with a standard long shaft the clamps will,I think, be 100 mm above the level of the cockpit floor

200mm above the waterline

is that enough? I would guess that is about the same as Katie L and this well is closer to the centre of the boat than Katie Ls

The well should accommodate a long shaft 9.8 and a long shaft 15 hp (not at the same time obviously)

the ultra long shaft will go much deeper

I will not know for sure until I get to a boat and have a good look around

all the details of the engine dimensions are here

http://www.keepturningleft.co.uk/scuttlebutt/designing-a-well/

the ultra long shaft outboard will be running pretty deep

does that matter?

will there be excessive back pressure on the exuast

all that aside

I was wondering if anyone had any tips on removing an inboard

can I remove bits to make it easier to shift

head off, fly wheel off?

then once it is free I assume I can slide it back wards into the cabin

then what?

Can four strong blokes lift it out?

can I use the boom as a lift?

will I need to make a frame?

once it is in the air - then what?

has anyone removed a Centaur fuel tank?

does anyone know of any urls of images of the job

Dylan
 
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I'd have thought it better to raise the power head than run the prop excessively deep. You're correcting the exhaust issue and reducing the possibility of swamping the engine. Why introduce two additional compromises when they can be self-cancelling?


As for removing the engine, I don't know what the Volvo lump weighs, but I took the BMW D7 off its gearbox and carried it off our last boat. The replacement Yanmar went in similarly, with slight assistance from a line lest it slipped off my shoulder as I scaled the ladder. 83 kilos with the box if I recall, so perhaps 70 without. The Volvo may be a good deal more.

Incidentally, I'm losing track with all the separate threads, so this one will have to do. The Centaur I mentioned has gone and I couldn't find the guy who won't give me all the 'cant tell you, data protection' balls, so no progress for now. Will seek him out Monday.
 
The top of the board should be 15" (375mm approx) above the waterline for a short shaft, so your 200mm is not enough, and completely out of the question for a long shaft.

Removing the inboard will depend on what is fitted. If it is a 23hp Volvo you will need a crane, or you will have to strip the flywheel off and probably separate it from the gearbox. The heads can also be removed fairly easily to further reduce weight. You can slide it forward and lift it with a beam across the companionway and using the mainsheet as a tackle or a hoist. You may be able to manhandle it out of the cockpit and over the side, but more than 2 people working on it at a time is difficult. I have done it in steps - up into the cockpit, onto beams across the deck, down onto an oil drum alongside, then down to a workmate and then ground.

Next time I paid £30 for a crane, stepped back and let somebody else do it. Took 3 minutes.
 
Tranona said:
The top of the board should be 15" (375mm approx) above the waterline for a short shaft, so your 200mm is not enough, and completely out of the question for a long shaft.

Removing the inboard will depend on what is fitted. If it is a 23hp Volvo you will need a crane, or you will have to strip the flywheel off and probably separate it from the gearbox. The heads can also be removed fairly easily to further reduce weight. You can slide it forward and lift it with a beam across the companionway and using the mainsheet as a tackle or a hoist. You may be able to manhandle it out of the cockpit and over the side, but more than 2 people working on it at a time is difficult. I have done it in steps - up into the cockpit, onto beams across the deck, down onto an oil drum alongside, then down to a workmate and then ground.

Next time I paid £30 for a crane, stepped back and let somebody else do it. Took 3 minutes.
Click to expand...

crane is the answer unless the boat is marooned at the back of a hard and out of reach of the crane

Dylan
 
Hi Dylan, I took my fuel tank out for cleaning, held in by 4 screws. Fiddly but doable - not a problem. You can strip the alternator, dynastart (depending on model) and take the head off to save weight and give you more working space. The flywheel is a heavy lump and held on by a whacking great nut, haven't tried that. Propshaft is easily reached. It will still be very heavy so a yard crane, hoist etc would be safer, try the boom if you think you are lucky!
 
If it's only 100mm from waterline to cockpit floor, I suggest you add the cost of a pair of waders to your budget.

If you want to keep the water out, I suspect you need to build the well substantially higher than the cockpit sole, which may mean modifying the tiller, but that's just a stick. No deal at all compared to the other mods.
 
dylanwinter said:
crane is the answer unless the boat is marooned at the back of a hard and out of reach of the crane

Dylan
Click to expand...

Yes, I know, which is why I described in detail how to do it without the crane. If the mast is up you can also lift it out using the boom as a jib and swing it over the side, but still best to reduce weight and do it in stages.
 
Not really keeping up with all this, but if you are taking a Volvo 23hp. ie. a MD11C out will you have spares to sell.
I am looking for an exhaust elbow as mine is split.
Capt. RoN.
 
MD11C weighs ~230kg with the gearbox; mind your back! For the well; it does sound a little low, either have a sliding bracket so you can mount at a convenient height then lower the engine to the operating height(like an Impala) or install an extra bulkhead ahead of the mounting bulkhead like on pretty much every outboard driven runabout speedboat.
 
Beware the Gods, Dylan

I knew there was something worrying me deeply about Dylan's obsession with removing the horsepower from a Centaur (with apologies if another insomniac has come up with the same concern) He could not have found a less appropriate vessel.
 
I too am getting confused with all the different threads!

I note that you've now introduced the possibility of a 15hp outboard into the equation. That, I believe, would be a better bet than the 9.8 and would largely overcome the issue of insufficient emergency power

it would probably be more economical too

still think it's a dumb idea though :-)
 
Re the depth of well
Assuming the lip is exposed ie not returned straight onto a flat surface, i would suggest making the top of the well higher than you calculate. Once in use you can see how high the swell comes up the well in a sea.you can also try the engine on a shallow set first. Once you have tried it you can then cut a bit off the top of the well & lower the engine. Each time you cut a bit off post the dimension on a thread. When you stop posting we will all know at what point the boat sunk & we will know the minimum height
Can i also ask if you intend to leave the engine in the well. I assume that when you are not on the boat you will remove it to avoid weed & erosion to the shaft. If you remove it to go sailing then you need a box to slide in the hole. This will reduce "sea slop" & give a faired in hull with no hole to slow you down. You can keep tools etc in the box so the volume will not be wasted when the engine is being used. Make sure you put a lip round the top of the box otherwise you will consign the contents to a watery grave the first time you use it
 
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apologies

Daydream believer said:
Re the depth of well
Assuming the lip is exposed ie not returned straight onto a flat surface, i would suggest making the top of the well higher than you calculate. Once in use you can see how high the swell comes up the well in a sea.you can also try the engine on a shallow set first. Once you have tried it you can then cut a bit off the top of the well & lower the engine. Each time you cut a bit off post the dimension on a thread. When you stop posting we will all know at what point the boat sunk & we will know the minimum height
Can i also ask if you intend to leave the engine in the well. I assume that when you are not on the boat you will remove it to avoid weed & erosion to the shaft. If you remove it to go sailing then you need a box to slide in the hole. This will reduce "sea slop" & give a faired in hull with no hole to slow you down. You can keep tools etc in the box so the volume will not be wasted when the engine is being used. Make sure you put a lip round the top of the box otherwise you will consign the contents to a watery grave the first time you use it
Click to expand...

the mention of the 15hp is because of the feedback on here

it is an option if I keep the well low

the long shaft engine would allow the top of the well to be 300mm above the waterline

but that would guarantee a large change to the tiller

depest apologies for the multiple threads

I thought they were different enough questions

and once a thread gets too long you get too many blokes argueing about scottish food and anyone who knows anything about removing engines wil not stick with the thread that long

besides ... boring threads drop like a stone and I do my best to avoid double posting

I think I have done as much asking as I need

and as much as many people can tolerate

back to nice long apostrophe threads

D
 
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Yes, I'm beginning to regret starting the apostrophe thread. Still, it gives erudite sailors something to think about during the sailing off season
 
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You might like to consider having the sides of the outboard well lip bevelled upwards from the outboard clamps, in order to retain a reasonable margin of safety when the boat is heeled.
 
Slamming

Our 31' bilge keeled Westerly used to sometimes slam badly in big seas. Presumably this was because when we came off a wave there was nowhere for the water to go between the keels. If there was a hole aft of the keels what is there to stop the water surging up and swamping the outboard ?
 
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