Blocked cooling engine block holes

[Bow42]

Water channels in my engine are badly blocked with salts deposits .
What can use to clear them ? .
Would H C acid damage the engine ? .

The Engine is an ferryman sea water cool .

 

[Tranona]

You may be able to chip some off, but it is often very hard. Brick cleaner is commonly used to help break down the deposits. Be careful about physical removal as there is sometimes the possibility of breaking into the casting.

 

[neil_s]

If you're talking about limescale, I use Fernox DS3 in my Bukh with good results. The limescale seems to build up in the cylinder head over about 5 years or so, until the engine can no longer sustain full revs without overheating. I circulate the DS3 solution through the cooling system for about one hour at a fast idle and - full power once again!

 

[nemodreams]

Are you talking about inlet pipes - or in block castings
The only place i could see the water channels is at the thermostat housing stripped off - at the head - or the engine zinc plate ?
What often happens in the head is some of the water ports in the head gasket can be quite small - often near the temp sender. If one blocks - the head is still being well cooled - but the water near the sender is over temp. Mine was firing off the temp gauge - and I could feel the engine was not overhot. When I did the head I realised why. One small 6mm head gasket 'hole' was blocked up. The rest of the head was quite clean.
After 20 years 'unopened' I was surprised how clean the water jackets were on a raw seawater cooled engine ( Igm10 )

 

[Spuddy]

HCl worked well for me. Don't forget to take engine anode out.

 

[Bow42]

Someone suggested vinegar to day , or coke cola.

 

[Bav34]

My local Volvo dealer sells and uses RYDLYME.

Plenty of YouTube videos.