I've just replaced the three anodes in this (seawater cooled) diesel engine. I noticed some corroded bits of the anode inside the head so I wondered if there was some type of coolant flush that I could use to dissolve and flush out these bits and what ever else is in the pipes. Perhaps something that I could pour into the primary water filter while the engine was running. It would then get pumped through the cooling system and ejected out the wet exhaust - hopefully taking potential pipe clogging debris with it.
Any suggestions for a product to use?
Select to expand quote said..
I've just replaced the three anodes in this (seawater cooled) diesel engine. I noticed some corroded bits of the anode inside the head so I wondered if there was some type of coolant flush that I could use to dissolve and flush out these bits and what ever else is in the pipes. Perhaps something that I could pour into the primary water filter while the engine was running. It would then get pumped through the cooling system and ejected out the wet exhaust - hopefully taking potential pipe clogging debris with it.
Any suggestions for a product to use?
I would not worry about it....as the anode bits are reactive, and are in a turbulent environment, they will quickly dissolve, as for other bits, just standard auto radiator flush.
Hello Zilla, here's something that may interest you. I,ve seen these guys at the boat shows but never actually met anyone who has installed the system. Might be worth looking into.
www.salt-away.com.au/saltremoval/inboardengineprotection
What I did was fill the cooling system with vinegar and left it in the cooling system for a week did it a couple of times but I'm still not completely happy
I still had to turn down my pencil anode in my Bukhara dv20 to get it to fit
We have a yanmar 3YM30. The salt water cooling side & heat exchanger tends to get blocked by a calcareous shelly marine growth. We were going to try the vinegar solution, but our mechanic showed us some photos of an acid flush he uses to clean out the growth & deposits in the system
We are doing this next week, I'll post some details & let you know how it goes.
Poods
Select to expand quotePoodle said..
We have a yanmar 3YM30. The salt water cooling side & heat exchanger tends to get blocked by a calcareous shelly marine growth. We were going to try the vinegar solution, but our mechanic showed us some photos of an acid flush he uses to clean out the growth & deposits in the system
We are doing this next week, I'll post some details & let you know how it goes.
Poods
I wonder what acid Poodle???? love to know that one 
Draino comes to mind Ha Ha any one seen my Buhk head
Drano is caustic as in a very strong alkaline (ie the opposite of acid).
Salt deposits in an engine are mildly alkaline like baking powder (bi carbonate of soda or sodium bi carbonate).
Vinegar is a mild acid.
Mix the right amounts of baking powder and vinegar in a sealed container and you will have a violent reaction that will constitute a bomb.
I believe the vinegar treatment for a salt water cooled engine repeated three times in a week will achieve the desired result of de-scaling the engine block but if it is contained (sealed strongly) it will most likely achieve the undesired result of a cracked engine block.
I could be wrong but that is my understanding of it.
Acids and alkalines mixed together usually react and produce a neutral substance.
You wonder how successful using something like this http://www.gates.com/products/automotive/tools-and-sales-aids/professional-tools/power-clean-flush-tool would be if you removed the outlet hose from the raw water pump and stuck it in there using mains pressure and compressed air
Regards Don
It's not that hard to google for industrial boiler descaling and then interpret the information to be applicable to marine use. It seems to me that everyone is overthinking the problem, rather than than keeping it as simple as possible, it's like lets make it really difficult so that we have to throw another thousand at the boat. Reduce from the complex to the simplex.
Select to expand quoteLooseChange said..
It's not that hard to google for industrial boiler descaling and then interpret the information to be applicable to marine use. It seems to me that everyone is overthinking the problem, rather than than keeping it as simple as possible, it's like lets make it really difficult so that we have to throw another thousand at the boat. Reduce from the complex to the simplex.
Hi Loosechange
Your no fun at all
Regards Don
Know what you mean about spending money on boats
Some of the figures on the "sold for a profit" thread are a bit of a eye opener
Regards Don
I open the seacock when I go onboard and close it when I finish for the day. That's the planned maintenance schedule I have for the next 30 years. I wont make it that long but if I did I would just replace the engine with another MD7 Volvo. Regular oil changes with the correct old style oil and clean diesel is all they need.
Hi Zilla,
the product you want to use on your cooling system is Rydlime. It is specifically designed to dissolve rust, salt, shells ect from marine engine cooling systems. Have a look at www.rydlyme.com.au as it is a great product and worked extremely well on my Yanmar 3QM30. The product has been around for over 60 years. It can be used on both raw water cooled engines and used to clean the salt side of heat exchanges. It does not hurt gaskets but you will have to replace your anode. I used a bucket with a bilge pump and two hoses, one to the engine block, bypassing the impeller, the other at the outlet bypassing the exhaust leading back to the bucket. Rydlyme provide instructions on their web site if confused. On my engine I was amazed when I replaced the anodes to find that that the corrosion and encrusted salt blocking the cooling system simply dissolved away. I found the Australian distributor very helpful.
Just an update on our marine growth encrusted heat exchanger, we managed to get some vinegar back through the heat exchanger, let it sit for a few days, it actually improved things a lot.
We will do a proper engine flush in the near future, product we've been recomended is called Barnacle Buster.
A quick question for any other 3YM30 owners - As far as I can tell, there are no anodes on the seawater cooing side of the circuit. I would have thought there'd be at least one anode, an easy screw out number that we would replace.
Does anyone know if there is a hidden anode?
Yanmar sites & engine manual only talk about the underwater anodes on the prop & SD.
Poods
Not an answer to your question Poods but some info on cleaning scale from salt water cooling systems.
I drained my Yanmar 2QM 15 salt water cooled engine block of salt water and then flushed it with fresh water with a hose from the marina to flush out loose solids.
Then I filled the system with straight white vinegar. After a few minutes froth came out from where I poured it in and continued to do so for an hour or more. It is obviously reacting something away.
A friend tells me he uses Septone Rust Converter ( a diluted phosphoric acid) to pickle his heat exchangers. Says it works a treat.
Select to expand quotePoodle said..
A quick question for any other 3YM30 owners - As far as I can tell, there are no anodes on the seawater cooing side of the circuit. I would have thought there'd be at least one anode, an easy screw out number that we would replace.
Does anyone know if there is a hidden anode?
Yanmar sites & engine manual only talk about the underwater anodes on the prop & SD.
Poods
There is no mention of anodes in the downloadable service manual. If there are any they would usually be located in the end caps of the of the cooling bank.
Anodes are used in engines with heat exchangers. They of course only have a fresh water coolant in the block and need anodes in the heat exchanger where there is a mix of metals. Raw cooled engines just have seawater circulating in cast iron and the only real mix of metals is steel and cast iron at the headgasket. The pump is of course bronze. No anodes in my Volvo, I will have to throw it away in 30 years time!
Select to expand quotecisco said..
Not an answer to your question Poods but some info on cleaning scale from salt water cooling systems.
I drained my Yanmar 2QM 15 salt water cooled engine block of salt water and then flushed it with fresh water with a hose from the marina to flush out loose solids.
Then I filled the system with straight white vinegar. After a few minutes froth came out from where I poured it in and continued to do so for an hour or more. It is obviously reacting something away.
A friend tells me he uses Septone Rust Converter ( a diluted phosphoric acid) to pickle his heat exchangers. Says it works a treat.
Just on the acid watch, our mechanic warned against using just any ordinary acid wash to clean out the marine growth.
They used to use some type of acid - not sure what it was - It cleaned things up a treat. problem was it also etched the bronze / brass lining, giving the marine growth a great new habitat to latch onto! 
Will let you know how the barnacle buster goes. 
Poods
As TKNick says- Rydlyme.
I would not go near home brew concoctions or acids.
The risk ain't worth it, unless you have plenty of cash laying around to replace a STUFFED ENGINE.
I run 10 litres of fresh with saltx mixed in a container for our BMW d8 ..dad always told me if I couldn't find I simular product 1 litre of Coke should do the trick!http://www.saltx.com/saltx_world_australia.htm
