Bukh DV20 - Coolant Drainage Plug

[Rafiki]

When I had a Bukh I set up a continuous loop system to catch the water coming out of the exhaust in a bucket with a hose fitted to the bottom of it which I led through the cockpit drains, through the cockpit, and through the hatch finally clamping to the raw water pump. I initially put fresh water in the bucket and started the engine, with a little encouragement ( basically filling the hose with water) I could get the raw water pump to fill from the bucket about 3-4 metres away. I changed the water circulating a few times with a hose so as to try and get rid of the salt. Once the water circulating had got pretty hot ( maybe 15 minutes at tickover or a bit faster) I introduced 2 or 3 litres of antifreeze and waited till that had worked its way through the engine, then stopped the engine. and closed the water intake seacock. I was happy to run the engine for a couple of minutes or so, without the impeller in, to get round to the crane

 

[seumask]

To clear out the salt build up in the water jacket of the DV24 while laid up I used Rydlyme, a bucket and and submersible 12 water pump from a caravan. I removed the thermostat and applied the pumped rydlyme mixture to the out let pipe of the raw water pump, and drained the rydlyme mixture back into the bucket from the engine by disconnecting the out pipe from the exhaust manifold and connecting to a temporary pipe back to the bucket. I reckon you need 2 liters of Rydlyme for this job.
The first 10 minutes resulted in lots of Fizzing away of the salt build up, which eventually calmed down and after a couple of hours I flushed it out with fresh water before leaving the block filled with a cheap automotive Anti freeze for the rest of the winter, using this method you dont need to run the engine. PS don't forget to replace the Thermostat when you fill up with antifreeze at the end.

 

[wingcommander]

A link to my flushing setup . The bypass is blocked off with a simple plastic bag over the pipe and the hose refitted. The thermostat and anode are removed. The cleaner used is diluted spirit of salts. (Acid brick cleaner ). Pump is a simple bilge pump in bucket