Any wonder why my sterntube was leaking then?

FullCircle

FullCircle

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I publish here, for the delectation and amusement of the yachting public, the humorous attempt of the Jeanneau Craftsmen to centralise the fitting of my sterntube. They were so proud of their Friday Afternoon joke, that they covered it in Sikaflex hoping against hope that the Prat who bought the boat would never notice.
This has been an ever increasing bilge cooling and keel bolt corroding feature for nearly 2 years.
All is now revealed, and its yet another season shortening trip to the yard.

This one makes me really mad. It is just criminal. I dont usually show all the little malfunctioning things that have kept me amused since I bought the boat. If this was a used boat you would walk away wondering what other horrors lay elsewhere

Shame on you Jeanneau!!!!!!


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Sorry Jim, fairly new to techy terms such as stern gland ( in previous life, I'd have thought ... well, maybe not...)
But why does it look like a dolphin?Or am I 1 glass of rosé too far?
 
Wrong!! It most certainly is a warranty job, as I have a paper trail of registered complaint since September 05, and this is the last straw to fix it.
I discovered it by pulling at the rear of the stern tube by the volvo seal, and it moved! On moving, it lets a trickle of water into the boat. Let it go, and it slows to a drip. Motor (i.e. shaft rotating) and its off tot a trickle again. 8 gallons during Burnham Week.....
 
Great!... same problem on a friend's SO37.
My SO35 is only leaking when strongly heeling on the port side... but I could never be sure of the origin of the leak.
I'm thinking of buying a water-diviner's wand.
 
You should worry.....

Bro in law has recently sold his SO35 - similar vintage to yours I believe. Surveyor said that prop was suffering from de-zincification (sp?). An inspection of the additional external anode that he had paid extra for at purchase ( to prevent just such an occurance ) was in very good condition. Further inspection showed why it was in such pristine condition and the prop had suffered. Someone had forgot to connect the anode to anything.........!!!!

If it was not so serious, you would laugh.

And Bavs get all the stick! /forums/images/graemlins/grin.gif
 
....but that wasnt Jeanneaus fault, that was the commissioning yard. I have a wealth of that type of tale. They kept me busy every weekend fixing those.
 
[ QUOTE ]
...leaking when strongly heeling on the port side...

[/ QUOTE ]Please check your keel bolts and then check the keel housing. The Moquini had similar symptons and lost her keel, which resulted in the loss of six lives (do a google for Moquini).

Whilst in a marina, you could use your spinnaker halyard attached to a ponton cleat on a pontoon say two berths away, to heel her over and then do a search for the source of the leak.
 
As You say.
That is just Criminal.
I am in the process of renewing My stern tube and all that goes with it.
However the boat (a mobo, Scandinavian) is 24 Years old and the bits underneath are suffering from VAT and electrolysis.
So no complaints there.
Having had to get involved in this Area ,You have My sympathies
That Piccie though.
That is Seriously, Unforgivable bad workmanship.
"Jeaunnaeu Craftmanship"?
I,m lost for Words.
And that takes some doing /forums/images/graemlins/frown.gif
 
As a complete non engineer, can you explain to me why this is a bad thing? Many engineering parts have flexible components and seals, and sixaflex used correctly doesn't seem like such a bad idea. I know nothing about this sort of thing, so looking to be educated, rather than passing comment.
 
The shaft should be in line with the stern tube, although flexible couplings can cope with a little misalignment. The fixed part of the stern tube must be fixed, though.

It looks from the pic like the engine wasn't aligned properly so instead of sorting that out (a big job), the 2 bolt holes were drilled out oversize to allow the stern tube to be fitted off-centre. The gaps were filled with sikaflex, which of course is flexible, so the stern tube was able to move, hence the leaking.

In the worst case, a big jolt from the engine, or perhaps a line caught on the prop, could have caused such a gap to develop that the water flooding in could have sunk the boat.

If the engine wasn't going to be remounted, they should have re-glassed the hull and drilled new holes, which although slightly off-centre probably wouldn't have affected performance.
 
Jim will most likely jump in with his own comments later but as a bilge swabber take my word for it , it is the sort of leakage I would expect from an old wooden tub like Miss Ellie , not Full Circle . As Damo says , certain parts are supposed to be just right , not padded out to make things fit . Found that out years ago on my first tub
 
Various arrangements are engineered in Pleasure boats and Commercial vessels.
Ref the method of transfering drive.
The Eng to Propellor on a shaft driven vessel is particularly goverened by "Alignement" ie , everythng has to be straight.
Flexible couplings etc--- might be a help to, like in Your Computer World , to "take up some slack" ie blockers, Anti Virus CC cleaners, Nortons (always thought they were Motorbikes anyway)! and all that corrective stuff.
But , like Your Pute, if the origional set up is Duff, probs arrive.
If the job initially has not been "Programmed" or set up proper like.
Eventually the Sh%t will hit the Fan.
The Fan in this paritcular case is the Prop.
Propellor , out of line or wobbling, bad News.
As Damo says the stern tube is fixed.
The shaft is supported by a bearing at one end (cutlass bearing) and an in board thinghy at the other.
The flexible bit is usually inboard, aft of the gearbox and aft of the "stuffing box" gadgett is a seal which can take up a bit more shake.
The stern tube does not "Carry" the shaft, tiss the aforementioned thinghy bobs that support it.

Plus to keep things straight as mentioned.
Without said tube the prop shaft would have no "Home" and would rattle about in the hull.
Plus where would one affix the bits that keep the Water out give some support?
Silkaflex, an Admirable product will not perform the job in total.
Is ok for sealing little gaps and weeps.
Won't secure the difficulties of a Shaft through a hull etc.
The "holes" are there for bolts to affix.
The bolts stop the whole "Job" twisting.
Ie to stop the Cutlass log "undoing "off the the stern tube.
There is normally a thread on the end of the Stern Tube which the cutlass log scews on to.
See www.diybob.com and www.e-marine-inc.com and search the Forum!
 
I'm never going to be an engineer!

I'd like to know what that picture meant in real terms tho. With lots of explanation, and preferably diagrams.

Forgive me, just been reading Patrick O'Brian series, and many of the terms in there leave me lost as well. Royals? Just figured those out.
 
Cripes!
Yer asking for Pictures?
"A Picture makes a thousand Words"
So the Ditty goes.
I don't do Pictures very well.
As everyone knows.
So get your puter brain in gear.
Yer aint gonna get no pics from here.
Some ryhming slang might come your way.
"Pictures" maybe another Day,
But just for now My Forum friend,
OK My boll%cks will could drive one,
Round the bend
in the Tube could sink the ship
So just read my words
That's your hardship! /forums/images/graemlins/grin.gif
 
I read the pic as follows:

You are standing under the hull, on the centreline, looking forward;
The large hole should be centered on the prop shaft (which has been removed, but you can see where it fits into the gearbox coupling);
The hole has been enlarged downwards and slightly to port so that the stern tube is centered on the coupling, and you can see the remains of the sikaflex at the top and slightly to starboard where the gap was filled;
The 2 smaller holes should be perfectly circular, with very little clearance, to take 10mm or 12mm (possibly) bolts;
There are 2 bolt flanges on the aft end of the shaft seal (inside the hull, removed), which match the bolt flanges on the bronze fitting on the outside(also removed). Depending on the hull the outer fitting may take the cutlass bearing, which stops the shaft from flapping about, or it may be on a separate P-bracket or similar. (There could also be a bronze stern tube that screws into the inner and outer fittings).Whatever, those bolts should be a very snug fit;
Any misalignment of the shaft with the shaft seal/stuffing box can lead to the seal not sealing on the shaft, hence leakage. A fitting that is able to float about is a disaster waiting to happen.

Hope this has helped, but have a look in Calder's books for good diagrams and explanations.
 
Basically correct.
The bolts and their holes , the size of which You have described is correct, are only there to stop the Cutlass bearing and it's holder"The log" turning.
The Log will be attached to the Stern Tube , normally by a thread which is turned on the Stern Tube.
Am I making Myself clear?
 
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