Changing an immersion heater element

[Slim]

1 hour ago, Alan de Enfield said:

Ensure you do it 'hot' and with the tank FULL of water.

The copper is so thin that without the support of the water it will twist and burst.

The heat will allow expansion of the tank, and it will be greater than the expansion of the element which will help to free-it-off.

I WILL ensure that the tank is full. After my abortive effort yesterday I had to drain it as it had developed tiny weep. It has a dedicated, plumbed in diaphragm pump. As for getting the water hot that's not so easy. This PM I'm going to see if I can restrict flow through the skin tank in any way. Thinking along the lines of one of those pinch claims used on brake lines.

Any more ideas, keep them coming. I may not use them but I will consider them.

I'll post with outcome.

[TheBiscuits]

  

21 hours ago, Slim said:

I tried to heat it up by running the engine (stationary) with little effect . I intend to take the boat for a short run tomorrow but I don't hold out too much hope of getting significant heat into the tank..

 

1 hour ago, Slim said:

As for getting the water hot that's not so easy.

 

Take it for a long run.  It can take a long time to get up to temperature, especially if you are not working the engine hard.  Speed up past moored boats ... 

 

[Slim]

3 minutes ago, TheBiscuits said:

  

 

 

Take it for a long run.  It can take a long time to get up to temperature, especially if you are not working the engine hard.  Speed up past moored boats ... 

 

Just been down the engine hole and clamped off the pipe returning water from the skin tank. It's a new silicone one so very flexible. Going home tomorrow to pick up the impact wrench and have a shower. Back Tuesday to pick up modified box spanner, give the boat a run up and down the marina, over to the pumpout (sorry for swearing) then see how things are. 

[MtB]

3 hours ago, Slim said:

Just been down the engine hole and clamped off the pipe returning water from the skin tank. It's a new silicone one so very flexible. Going home tomorrow to pick up the impact wrench and have a shower. Back Tuesday to pick up modified box spanner, give the boat a run up and down the marina, over to the pumpout (sorry for swearing) then see how things are. 

 

 

Curious now. What sort of impact wrench is this you're gonna use?

 

Immersions loosen far better stinking hot than cold. Even if you only use a blowlamp liberally on the boss and immersion head it still works even though the water inside conducts the heat away very quickly. 

 

If you can't get it out then davidg's suggestion of emptying it then blowlamping it sometimes works just as he describes, but sometimes not and beware of getting the copper red hot, all the strength of the metal disappears when red hot and you'll twist the boss off shockingly easily if too hot with no water, and still tight. 

 

 

 

[TheBiscuits]

4 hours ago, Slim said:

give the boat a run up and down the marina, over to the pumpout

I was thinking more of a 4 hour out-and-back cruise at generous revs ... 

[Slim]

Mike

Just looked it up . It's a Goeeeeè ? obviously Chinese, impact wrench, 18 v cordless 300nm 1/2 drive .It's adjustable for torque setting so I can start off gently.  Looks like a drill or cordless driver but fairly powerful. Like they use in a garage to remove wheels or stubbon nut/bolt. In no way an I sure it will work but it will allow me to offer up the box spanner square to the heater nut an exert a rotary force with no sideways pull. Time will tell and what have I got to lose?

 

Biscuit 

I take on board your point fully. If it doesn't loosen 'easily' I'll take myself up a couple of locks and back again. 

 

Lets face it the entire world is in a state of flux, why shouldn't my boat be as well.

[Slim]

Well, a couple of months down the line and many things have happened. It's quite frustrating having an outstanding job for so long. Having said that my issues have been miniscule compared to those of many others.

With easing of restrictions I was able to get to the boat today. Picked up the modified box spanner (thanks Richard) and gave the impact wrench it's head. Wasn't easy but IT WORKED!

New immersion in , wired and working.

I truly feel chuffed.

Thanks to everyone for their advice.

[mrsmelly]

19 minutes ago, Slim said:

Well, a couple of months down the line and many things have happened. It's quite frustrating having an outstanding job for so long. Having said that my issues have been miniscule compared to those of many others.

With easing of restrictions I was able to get to the boat today. Picked up the modified box spanner (thanks Richard) and gave the impact wrench it's head. Wasn't easy but IT WORKED!

New immersion in , wired and working.

I truly feel chuffed.

Thanks to everyone for their advice.

Now all you need to do is shoot the eeejut that fitted it like that in the first place.

[Slim]

15 minutes ago, mrsmelly said:

Now all you need to do is shoot the eeejut that fitted it like that in the first place.

That was me!. Hey ,I thought I wasn't talking to you. ? Life's too short

[mrsmelly]

18 minutes ago, Slim said:

That was me!. Hey ,I thought I wasn't talking to you. ? Life's too short

OOps sorry I hadnt realised you did the original fitting  reminds me of when I fitted a water pump years ago in the galley and put a kitchen unit in top of it and realised later I would have to get rubber man onboard if I ever needed to change the pump lol. I sold that boat before it went pop luckily.

[alistair1537]

Nice one! Any pics of the modified box spanner? For future reference?

 

 

[ditchcrawler]

3 hours ago, alistair1537 said:

Nice one! Any pics of the modified box spanner? For future reference?

 

 

CWF rent a tool ?????????

[WotEver]

9 hours ago, alistair1537 said:

Nice one! Any pics of the modified box spanner? For future reference?

 

 

See post #8. 

[Slim]

2 hours ago, WotEver said:

See post #8. 

I will post a photo but my post 8 describes. The only 'improvement' was that instead of a nut being welded to the plate Richard welded on an old 22 mm 1/2" drive socket.  This gave much better control.  

[WotEver]

33 minutes ago, Slim said:

I will post a photo but my post 8 describes. The only 'improvement' was that instead of a nut being welded to the plate Richard welded on an old 22 mm 1/2" drive socket.  This gave much better control.  

Yes, that sounds like a better solution.

 

The great thing about this mod of course is that there's no twisting moment to the force you apply; it's all centred on the element.

[robtheplod]

Ours only budged after a several hour cruise after spending days on it beforehand.... good luck

[alistair1537]

The reason I asked is, I had an old immersion tank the other day, that was built into a cupboard - limited access - to further complicate things the tank was turning whenever I applied force to the spanner - eventually I had it out - a co-worker hugged the tank to prevent it from turning - a long bar - 400mm x 16mm - larger hole drilled through the socket and repeated hammer blows...free'd it off millimetre by millimetre...worst one I've ever come across. So an impact wrench sounds like a solution should I run into a similar job.

Edited May 17, 2020 by alistair1537
grammar

[Slim]

On 16/05/2020 at 18:29, Slim said:

I will post a photo but my post 8 describes. The only 'improvement' was that instead of a nut being welded to the plate Richard welded on an old 22 mm 1/2" drive socket.  This gave much better control.  

Here are photos (I hope)

[alistair1537]

Cheers - that looks the business! Just don't be tempted to tighten it back up with that!!