Vincentc
Legendary Member
- Joined
- Jun 3, 2008
- Messages
- 1,514
- Status
- OWNER - I own a Hatteras Yacht
- Hatteras Model
- 43' DOUBLE CABIN (1970 - 1984)
A Phosphoric Acid solution worked well for me in flushing the raw water systems for the Detroits, generator and AC.
Engine operating temperature dropped roughly 30 degrees and sea water flow through the generator doubled.
I had concerns regarding acid concentration and checked the MSDS for Barnacle Buster, Ospho, and Klean Strip Metal Etch.
BB ready to use lists 10-30% phosphoric acid and the BB concentrate is 60-80% acid with instructions to dilute 5-1.
I concluded that a 15-20% concentration of phosphoric acid would be about right.
The boat supply store here had only a product called Phos-foe which looks a whole lot like Ospho.
They only had 4 gallons in stock so I went to Lowes and found the Klean Strip product and bought 2 more gallons to finish the jobs.
Both of these products cost $18-$23 per gallon which I understand is less than Barnacle Buster. Their MSDS indicate a phosphoric/orthophosphoric (different name, same product) concentration of 40-45%.
I diluted the products roughly 2.2 parts water to 1.
A bilge pump, with 5/8" hoses and a 5 gallon bucket allowed me to flush the Detroits and the AC in 2 directions.
Access problems due to the generator being installed next to bulkheads on 2 sides required me to simply feed the acid solution through the generator while the engine was running, stop the engine when the system was full and let it sit about 45 minutes.
I did not add any other product to the acid/water solution nor did I inspect the heat exchangers post acid flush.
The restoration of normal operating temperature and observed increase in water flow out the exhausts was enough for me.
I also replace impellers on the main engines and generator. The impellers were all in tact.
I learned that it is near impossible to put new impellers in the pumps while they are mounted on the engines, and not very challenging with the pumps in a vice.
Removal/replacement of the pumps was simple, so long has you have a spare mounting gasket on hand.
Engine operating temperature dropped roughly 30 degrees and sea water flow through the generator doubled.
I had concerns regarding acid concentration and checked the MSDS for Barnacle Buster, Ospho, and Klean Strip Metal Etch.
BB ready to use lists 10-30% phosphoric acid and the BB concentrate is 60-80% acid with instructions to dilute 5-1.
I concluded that a 15-20% concentration of phosphoric acid would be about right.
The boat supply store here had only a product called Phos-foe which looks a whole lot like Ospho.
They only had 4 gallons in stock so I went to Lowes and found the Klean Strip product and bought 2 more gallons to finish the jobs.
Both of these products cost $18-$23 per gallon which I understand is less than Barnacle Buster. Their MSDS indicate a phosphoric/orthophosphoric (different name, same product) concentration of 40-45%.
I diluted the products roughly 2.2 parts water to 1.
A bilge pump, with 5/8" hoses and a 5 gallon bucket allowed me to flush the Detroits and the AC in 2 directions.
Access problems due to the generator being installed next to bulkheads on 2 sides required me to simply feed the acid solution through the generator while the engine was running, stop the engine when the system was full and let it sit about 45 minutes.
I did not add any other product to the acid/water solution nor did I inspect the heat exchangers post acid flush.
The restoration of normal operating temperature and observed increase in water flow out the exhausts was enough for me.
I also replace impellers on the main engines and generator. The impellers were all in tact.
I learned that it is near impossible to put new impellers in the pumps while they are mounted on the engines, and not very challenging with the pumps in a vice.
Removal/replacement of the pumps was simple, so long has you have a spare mounting gasket on hand.
