Marine Diesel Raw Water Cooling system flush with Rydlime

Today’s projects were servicing the engine cooling systems. This is a raw water cooling system flush on the Yanmar engines. You can use either Rydlime or Barnacle buster. I chose Rydlime (diluted 1/1 with water) because it is a bit safer to work with, both for me and the aluminum. It is a mild acid, so use gloves and wear glasses. This engine doesn’t have zincs, but if yours does, replace the zink after, as it will get dissolved. Remove the impeller. You can also do this for your generator and A/C units on the raw water side.

[@AndysEastCoastAdventures]

Did the same on my Yanmar 1gm10 recently as was getting clogged up with scale. Used 1lt of brick acid in a builders bucket topped up with freshwater. Got the same result as you with that dark grey residue in the bucket and cooling system seems to be clear now. Its cheap stuff so will do this as part of my annual servicing from now on.

[@sighpocket5]

Nice!!!

[@taylorhurst4735]

can you flush out the fresh water side of the system?

[@stryder0559]

I’m wondering that as well. What to use to clean out the radiator and system

[@AndysEastCoastAdventures]

You can buy stuff for keeping your freshwater side clean. Although it should be coolant in their and not plain freshwater.