White stuff on engine casing

[wrongfontagain]

Noticed this white deposit on my engine yesterday: is it par for the course or anode not doing its job anymore? When it comes to engines I'm virtually in the dark (promised myself to do a course this Autumn!) so any help and advice taken onboard with much thanks.

 

[Ruffles]

Noticed this white deposit on my engine yesterday: is it par for the course or anode not doing its job anymore? When it comes to engines I'm virtually in the dark (promised myself to do a course this Autumn!) so any help and advice taken onboard with much thanks.

It's the colour of the limescale you get when there's a water leak. But there seems to be a lot of it! Is it losing fresh water?

Looks too high up to be the raw water unless it's the syphon break. If that's leaking it could be running down the hose onto the engine.

BTW the engine doesn't have anodes as it's freshwater cooled.

 

[Dave_Seager]

It looks as if you have a small leak somewhere near the top of the white trail. The leak is probably seawater and the white stuff will either be common salt from the water or other salts from corrosion of the metal it has contacted.

Your anodes probably have nothing to do with this unless they have been left so long that internal corrosion has caused the leak. The engine and surroundings appear to be fairly new so I would be surprised if it is more than a slight weep from a gasket or hose fitting.

 

[Tranona]

Yes, thats a seawater leak from somewhere. Rather odd because the seawater bits look OK and the deposits are around the freswater pump (driven by the belt). Best to find the source quickly as not only is it unsightly, but the front cover will eventually corrode.

 

[Ruffles]

I reckon it's the syphon break. Water could be running down the hose on the right and dripping onto the FW pump where the pipe bends. Should be obvious with the engine running.

The syphon break ought to be washed out annually. Otherwise it gets bunged up with salt deposits. Take it off and wash it in the sink.

AND ... there should be a smaller pipe on the air inlet of the syphon break that leads round the engine. In case the valve leaks!

 

[neale]

BTW the engine doesn't have anodes as it's freshwater cooled.

My experince is with larger mobo engines but would a fresh water cooled yacht engine not have an anode of the heat exchanger?

 

[Tranona]

Depends on the metals in the heat exchanger. Some do but many, like the Volvo don't

 

[tawhiri]

I have a slight build up of white powder on my engine from time to time similar to the battery terminals. The saildrive anode was changed regulary, and seemed to be nearly as good as new after each year haul out. However the aluminium prop was almost completely disolved after four years. If I understand correctly the Volvo saildrive should be galvanically seperated from the engine to mitigate electrolysis. In my case there is 70 ohms continuity between engine and saildrve. This could be be the reason.
Hope this helps Andrew

 

[VO5]

It looks like you have more than one seawater cooling leak, very small ones though.

I would suggest you thoroghly clean out the encrustations then liberally dust all over with talcum.

That should reveal the sources.

Then you can deal with them.

 

[wrongfontagain]

Thanks guys (I think this Forum is a fantastic resource). Cleaned the area last night and intend on running the engine over the weekend prior to sailing and will keep tabs on the leak. Talcum powder trick seems like a good idea. Although on second thoughts it might be better to run her in gear on a good springer in the marina. Thanks again to all.

 

[Heckler]

Noticed this white deposit on my engine yesterday: is it par for the course or anode not doing its job anymore? When it comes to engines I'm virtually in the dark (promised myself to do a course this Autumn!) so any help and advice taken onboard with much thanks.

Looks like a VP20X0 engine, that is the fresh water pump, it is alumimium, mine went like that, the paint flaked off and the alloy slowly oxidised. There arent any internal anodes in this engine.
It looks more advanced than mine was. Check if there is any sea water dripping from anywhere on to it.
The pump is quite expensive and you need 2 gaskets to sort it. one for the steel backplate that it sits on, may as well change the thermostat while you are at it.
Stu