raw water cooling - Anodes

[grayclose31]

Hi All,

I am considering using my 20ft cruiser on the sea.

Currently the engine is coolled directly from fresh/raw water.

I am aware that the simple answer is to fit a heat exchanger but have been told that i can just fit anode's to the engine toprevent corosion.

Please understand that the boat has a car engine fitted inboard (Cavalier 1.7 turbo diesel).

I am not looking tospend hundreds of pounds on the cooling system.

I have also concidered making it a sealed system to include a radiator and electric fan.

Just looking for opinions or options if anyone else has done anything like this.

Thanks Chris.

 

[rafiki_]

I have a pair of the Isuzu 1.7D engines used in the Astra, marinised and supplied by Mercruiser in my boat, with Alfa 1 Gen 2 outdrives. These are fresh water (sealed) cooled, using raw water into a heat exchanger. There are anodes in the heat exchanger system. You can only purchase salt water anodes to my knowledge, as non brine river water is unlikely to do any damage.

Are you saying your engine is a 1-off out of a Cavalier, home marinised?

 

[grayclose31]

I have a pair of the Isuzu 1.7D engines used in the Astra, marinised and supplied by Mercruiser in my boat, with Alfa 1 Gen 2 outdrives. These are fresh water (sealed) cooled, using raw water into a heat exchanger. There are anodes in the heat exchanger system. You can only purchase salt water anodes to my knowledge, as non brine river water is unlikely to do any damage.

Are you saying your engine is a 1-off out of a Cavalier, home marinised?

Yes i have the same engine fitted in my boat as you have.

I want to marinise it and was asking if i could return the engine to a closed system that is used in a car or could i just add anodes some place in an open system.

 

[rafiki_]

As I mentioned above, there is a fully marinised version, and you could buy the parts from CumminsMercruiserDiesel (CMD) with a bit of a google. However, this is an expensive way forward. You might try https://login.yahoo.com/config/logi...oup/cummins_mercruiser_120hp_DTI/messages?o=1

This is dedicated to the 1.7. You will see many horror stories on here, mainly due to poor maintenance, but you might find someone who has gone down the same route as you.

 

[Spi D]

You do not state your boat make or model, but FWC really is a good idea in salt water.
Several kits are available (at a cost ) and if your boat allows, even running tubes on the outer hull is an efficient 'cooler'.

These 8 tubes are sufficient for a 500 hp Cummins N14 in a fishing vessel:

Another option with closed cooling is to make use of the heat in eg. a radiator for cabin comfort.