White smoke and dead batteries

[Tony Brooks]

I found on the hire boats that had similar inlet strainers to purple8's that if you turned the sea cock (red lever) off and removed the strainer a certain amount of debris would float to the outside of the strainer when it was put back in. Over time these tended to build up across the face of the heat exchanger tubes or in tight elbows in the raw water system - especially if an impeller wing had broken off and lodged across the elbow.

I would suggest that if the top of the strainer is below the waterline you turn the cock off, remove the strainer, turn the cock on so water inflow flushes any residual debris into the bile and at the same time look down the hole to make sure nothing is blocking the inlet hole in the hull. Then turn off etc.

I would suggest that this is a daily task.  especially on canals.

[Alan de Enfield]

3 minutes ago, Tony Brooks said:

......and removed the strainer a certain amount of debris would float to the outside of the strainer when it was put back in. Over time these tended to build up across the face of the heat exchanger tubes.......

I'm guessing that's why they install a secondary In-line filter in an easily accessible place between sea-cock and pump.

[OldGoat]

1 hour ago, purple8 said:

before I go do anything silly and flood the engine bay and sink the boat... This is where the boat draws its raw water and this leads to the impeller. If I turn the red cock (assume its the sea cock) and remove the top, this is where I can find the strainer or any blockage in this system?

Those strainers (above) are an absolute abomination on the canal system. They're designed for proper-salty-water-boats - that's why this one is bronze. On a canal you need a Mud Box. Mine's 6" x 6" and has a baffle plate so that most of the mud  (and creatures - I had a crayfish living in mine) gets caught. Even so the Vetus filter gets muck in it from time to time.

The above is fiddly to inspect - and like most fiddly items tends to be ignored  - "I'll do it later". I'd suggest fitting a Vetus filter anyway and possibly removing the mesh element (don't chuck it away) to let the Vetus do the job; mounting where maintenance is easy.

 

[purple8]

thank you all for ur input

I will be adding a temp gauge and new strainer in due course and will be sure to keep an eye on this more.

we will see if its solved the problem now as we go on our cruise. Will update u all later.

[rusty69]

4 minutes ago, purple8 said:

thank you all for ur input

I will be adding a temp gauge and new strainer in due course and will be sure to keep an eye on this more.

we will see if its solved the problem now as we go on our cruise. Will update u all later.

Good luck. 

 

I added a flow switch and audible alarm to ours to give an indication of problems. Also alerts you if you forget to turn the seacock on. 

[David Mack]

1 hour ago, purple8 said:

nice... Opened and it was filthy!!! Something to keep an eye on there!

If the top of that is above the outside water level, then you can open the seacock and rod or brush right through to get rid of debris around the inlet.

[Naughty Cal]

3 hours ago, Alan de Enfield said:

Being a 'bit of a prepper' I actually carry a complete raw water pump as a spare - it is far easier to swap over the complete unit than it is to hang upside down trying to unscrew  several face-plate screws, jiggle out the old impellor, check everything, and re-assemble.

 

'Maintenance' work can then be done 'on the table' in the comfort of being 'the right way up' and that unit then kept as a spare.

 

Pic showing how the vanes get squashed to provide the pumping action - not a lot of room for them to turn around if you put them in the 'wrong way'

 

 

We bought a Speedseal plate to make changing the impellor quicker and easier should the need arise.

Not had an impellor fail since fitting this in 2011 I think it was. Prior to this the slightest water restriction shredded the rubber.

 

http://www.speedseal.com/SpeedsealLife/SpeedsealLife.html

[MtB]

8 hours ago, purple8 said:

could this have been my problem all along?! Hope so as that turned out to be a very simple thing!

 

I'd say yes this could easily have been the problem. The engine overheats after working hard for a while. 

Have another cruise and let us know!! 

[purple8]

so...

thanks everyone so much for your input and advise! I've learnt a lot in the past few days.

we completed a 2 1/2 hour cruise with no hic-ups what so ever. Engine purred like she used to throughout, no sign of any smoke, no belt squeals and we travelled much happier all the way!

for now the problem has passed, and I know a few things I must start to keep an eye on. But for now its time to open a beer

and mike, we also fixed the boiler thanks to a short phone call to bob, thanks for the info on that too

[Rob-M]

That's good to hear and well done for keeping the thread updated with your findings.

[Naughty Cal]

Just remember to keep checking that filter.

[GUMPY]

Glad its sorted before  much damage was done to the engine. 

Now what about that bad battery......?

[ditchcrawler]

This Thread may give you some thoughts and this Link on what he did http://boatbuildblog.blogspot.co.uk/2012/03/mud-box-mods.html