Arwen's meanderings

Hi everyone and welcome to my dinghy cruising blog about my John Welsford designed 'navigator' named Arwen. Built over three years, Arwen was launched in August 2007. She is a standing lug yawl 14' 6" in length. This blog records our dinghy cruising voyages together around the coastal waters of SW England.
Arwen has an associated YouTube channel so visit www.YouTube.com/c/plymouthwelshboy to find our most recent cruises and click subscribe.
On this blog you will find posts about dinghy cruising locations, accounts of our voyages, maintenance tips and 'How to's' ranging from rigging standing lug sails and building galley boxes to using 'anchor buddies' and creating 'pilotage notes'. I hope you find something that inspires you to get out on the water in your boat. Drop us a comment and happy sailing.
Steve and Arwen

Friday 20 September 2019

a leaking outboard tank

Nope, it isn't the petrol cap. I discovered a hairline fracture crack on the neck of the tank, just below the screw thread area. It runs about 4cm around the neck on the 'up' side when the motor is tilted up in its locked position out of the water. After closer inspection, I then discovered another one above that!

I have for many, many years been into recycling and doing my best to avoid being part of the 'throw away and rapidly replace' culture. Dad, God bless him,  has always been an extremely talented make do and mend guy and some of that has rubbed off on me now I am retired. I am beginning to appreciate his jars of accumulated screws and nails, under the workbench boxes of scraps of wood and plastic, bundles of string and frankly lord knows what else. Dad has never yet failed to find something that answers the question...."Dad, you wouldn't by any chance have.........?" 
His shed is the TARDIS, despite how much junk Mum has him store in there!

Over the years I didn't do as much as I should have towards this 'make do and mend' philosophy - working 60 hr weeks in the teaching profession put paid to that and, interestingly, as an aside, the first long term survey/monitoring report ever into teaching workload hours in the UK has just been published today  - damning verdict - in 25 years despite successive promises from successive governments - nothing has changed on teacher work load. 35% of new teachers quit within five years of joining the profession; 25% are working 60 hrs plus; 50% work 50 hrs + per week. Excessive administration, marking etc takes 22 hrs per week minimum, 3/5 teachers have to work in their evenings just to stay afloat for the next day. We are offering £28,000 training bursaries to recruit enough geography teachers to meet a national shortage crisis - and that's just to geographers!

Teachers in Finland, which consistently ranks the world top education tables - work 34 hrs per week with smaller class sizes and spend several hours a week training and updating their skills. Their professional and social status is highly regarded by their nation. Says it all really. I retired reluctantly as soon as I could after 35 years of this and lost a quarter of my pension in doing so for the rest of my life - it was I surmised, worth it to protect health and sanity - you don't get those years back - but I left with some regrets - I'd have liked to have carried on until I was sixty, under better circumstances. Don't get me wrong - teaching has been a joy and an utmost privilege but it came with costs to family life, health and personal sanity. But then I guess in our country that can be said of very many professions and our successive governments just don't get it - maybe the New Zealand approach of looking at what is important to people and investing more time and capital in those things to raise happiness is actually a good idea. I'm sure New Zealand readers will have views on this and as always comments in the box below are welcome.


Anyway, back to the outboard, sorry for the slight frustrating deviation.


 My initial thoughts have been - "how do I repair this fracture so it is no longer a problem?"

There are various options that have been supplied to me by various FaceBook forum members and I am grateful to all those, who as usual, came to my rescue generously with their time and comments. The 'burning cartoon' memes were perhaps less helpful although a salutary reminder of the dangers of getting this wrong!!

After emptying the tank of fuel (typically I had just filled it when I noticed the slow trickling seepage stain over the foam sponge ring around the cap area)


  1. flushing it out with water and letting it thoroughly dry, heat gun seal through plastic welding the offensive crack
  2. rough up the area with 80 girt sandpaper and clean it thoroughly with alcohol wipes before applying epoxy - JB weld or G/Flex seemed the popular suggestions 
  3. using self amalgamating rubber plumbers tape - a piece stretched to x 10 its original length wrapped tightly around itself several times, apparently seals anything!
  4. get a new fuel tank
And that was basically it.

Sourcing a new fuel tank has been frustrating. My local chandler which I have used to get most fittings for Arwen said they could get one and fit it. Apparently it would be complicated work needing an hour and so the cost of getting and fitting would be £130 - £140.

It is a four stroke Tohatsu short shaft MFS 3.5hp outboard. The tank I can get for £90 in UK - cheapest I can find thus far although that search continues because that strikes me as outrageous.  careful investigation shows that all the nonsense given me yesterday about how the carb will need moving etc is pure tosh. I'm no engineer but all I can see is one fuel pipe coming out of that tank. It sits on a frame above the engine parts secured by three bolts. I have restored from a complete breakdown a 1960's Vespa scooter - how hard can it be to replace a petrol tank?  Am I missing something?

OK, I admit I'm not sure about the consequences of taking off the fuel pipe - does it mean I get an airlock somewhere after fitting it back? 

I don't know about these things, but fortunately, I am a member of  several forums who have members who do. I have a Dad who is a talented engineer and turns his hands to all sorts of things and a brother in law who works on the very best aeronautical engines you can get. Someone will be able to help this idiot!

And so, some decisions - do I try the repair and see what happens - or do I just go for the straight replacement.......answers on a postcard....soon please.....via the comment box.......because I don't go sailing in my neck of the woods without having a motor hanging off the back. I'm just not that gooda a sailor!

Postscript - after a suggestion from John Welsford, I found a plastic welder who charges around £40 an hour. He thinks it can be done but isn't sure. I guess it is time to exercise some common sense and bite the bullet by purchasing a new tank. It is, after all, a safety issue. 

Postcript 2 - talk about a struggle to find a new fuel tank - most retailers say a 6 week wait whilst it comes from Japan - however, one retailer of outboards took pity - but at a cost - £81. Anyway, he took the tank out of a new four stroke and has sent it to me so I can be out sailing next week all being well. He has a spare already in transit, about two weeks out. I guess it was a kind offer and so the extra £12 has been worth it. His nearest competitor was charging £69 but a wait of 6 weeks. 

6 comments:

Bursledon Blogger said...

Steve - do the repair, if it doesn't work then get a new tank but at least you will have learned what does and doesn't work.

Alastair said...

I would hazard that the reason you are "just not that gooda a sailor" is because you don't go sailing without a motor.
However I would advise, at that price:
1/ Try to find a scrap motor with a good tank.
2/ Try one of the chemical fixes.
3/ Bite the bullet and get a new tank.

Steve-the-Wargamer said...

When the (albeit metal) tank on my trusty old Yam went I managed to find a breaker in Wales who sold me a "new" one from an old engine.. it was a while ago - do outboard breakers still exist and might they have one for your engine? Elswehere, people constantly tell me that basically there are only two or three makers of outboards, and they are all the same and just re-badged - so would a new tank from a different engine be cheaper? Three... Petrol is fairly foul stuff - I would worry any repair with glue/epoxy would just fall apart.. I'm guessing you are too... Last - can you convert it to external tank???

steve said...

Hi Max - the plastic welder isn't convinced given there are two splits one on top of the other - so I am leaning towards the new tank. Steve - the local chandler did try to sell me a second hand one but it was from a different outboard and although very similar - it was clear it would take some really fiddly engineering to get it to sit soundly, so I abandoned that idea. I have tried epoxy and it hasnt cured properly despite cleaning the area thoroughly. Alastair - I'm a bad sailor not because I occasionally use an outboard but because I have no idea what I am doing when trimming the sails - and so never get the poor boat to sail efficiently. Arwen was only designed for rowing short distances. I rowed her into the Cattedown once - it didn't go well with all the tourist boats and water taxis and sailing her from out of the crowded marina is beyond my courage level. Discretion is the better part of valour and all that.
Thanks for the suggestions guys - appreciated as always.

Bursledon Blogger said...

Steve ref Steve the wargamer's idea. I converted a 5HP to external tank - actually so it could do both internal and external, the remote conversion was pretty easy and all up including the external tank,less than you've been quoted for a new tank.

Can't remember the engine but it was black so guessing Mercury. The external tank was really good never used the internal one again even though i could.

I think the only thing you need to check is if the carb has a diaphragm pump, I'm guessing most do these days as the arts diagram for mine only showed with.

steve said...

Hi Max - thanks for the tip - off to investigate further - I'm using one litre bottles at the moment but hanging off the transom in a bouncy sea is nauseating! So I'm exploring all options - thanks for the tips