Hydrocchloric Acid Cleaning

Yes I have seen the MSDS and the other info on Rydlyme

The MSDS says it is less than 10% HCl ~~~ so its hydrochloric acid based ?

but I cannot relate that to a claim on another page that 1 US gallon will dissolve 2lbs of calcium carbonate! I'd reckon it will only dissolve just over 1 lb !

So if its only 10% HCl what else is in there to push that 1 lb up to 2 lbs?

also I find the quoted pH of "UNREADABLE, GENERALLY <3" rather odd. 10% HCl will be a lot less than 3.
 
yes, one wonders how commercial labs manage to identify a pH <3 :)


In the specification pages, they say that it is heavily fortified with wetting and penetration agents, and para 8 seems to confirm that the concentrated form will dissolve 2lbs/US gal, as you query. I guess the wetting and penetration agents help physically loosen scale, which is then carried away by flushing ?

http://www.rydlyme.com/pdf/RYDLYME SPECIFICATIONS.pdf
 
A warning for anyone with a Bukh engine: the manufacturers apparently advise against using HCl in their engines because of possible damage to the seals of the wet cylinder-liners.

I believe these seals to be nitrile. The chemicals resistance chart says that nitrile is moderately resistant to concentrated HCl but OK in dilute. The data relates to constant immersion, not ten minutes when removing scale. The Bukh info seems to me to be over-cautious. The engine I have de-scaled with HCl was a Bukh.

The reason I suggested removing the thermostat was that it is brass, that may suffer some attack from dilute HCl. Probably not an issue but these components are outrageously expensive so not worth taking the risk.
 
Get some Muriatic acid, twenty per cent acid 80% water. Don't use pure Hyrochloric acid it's lethal if you get even a small splash on you. We use it to clean heat exchangers on our engine and generator. Works fine but don't leave it a day or two. The reason is the acid will only dissolve an limited amount of Calcium so keep flushing the acid through until it stops bubbling. If you do get some on you you will feel a slight burning sensation, wash it off as quickly as possible.

By the way Muriatic is brilliant for cleaning rusty stainless steel. It doesn't affect epoxy paint but I don't know about GRP or other paint. Brush it on carefully.
 
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A warning for anyone with a Bukh engine: the manufacturers apparently advise against using HCl in their engines because of possible damage to the seals of the wet cylinder-liners.

Yes I can confirm that overnight exposure to dilute hyrochloric acid will destroy the cylinder liners seals as my pal found out to his cost. Perhaps a few minutes would be OK though.
 
Muriatic acid, when in contact with water, becomes hydrochloric acid.

The reason to remove the thermostat is to not impede flow in any way. If the thermostat is closed, as it will be, the flow bypasses the cooling passages.

Best way is a bucket with a bilge pump in it. Remove the line coming out of the water pump and attach it to the bilge pump. Another hose from the outlet (normally into the exhaust elbow) returns it to the bucket. Just turn the pump on and let it circulate.
 
Get some Muriatic acid, twenty per cent acid 80% water. Don't use pure Hyrochloric acid it's lethal if you get even a small splash on you
Muriatic acid is merely an old name for hydrochloic acid.

It is a solution of hydrogen chloride, a gas, in water.

You should check the concentration of any muriatic or hydrochloric acid you buy as it is avaialble in a wide range of concentrations.

Ordinary laboratory "concentrated" hydrochloric acid is approx 36% by weight of HCl.
Higher concentrations are, for obvious reasons, called fuming hydrochloric acid. 40% is the most concentrated generally available.

I dont know what Kelly's eye is calling "pure hydrochloric acid" No such thing really apart from hydrogen chloride gas, as there are only solutions in water up to the concentration figures above.

As for "it's lethal if you get even a small splash on you" Well I am still alive! So a bit of an exaggeration perhaps
But remember if using it in the marine environment it is lethal to fish from 25 mg/l up and generally toxic for aquatic organisms due to pH shift.
 
>As for "it's lethal if you get even a small splash on you" Well I am still alive! So a bit of an exaggeration perhaps

I've seen the scarred face of somebody who had their face covered with Hydrochloric acid when a Chemistry experiment went wrong. Muriatic acid wouldn't scar a face because it's so diluted.
 
Of course, it's important to establish what sort of scale you have in your Volvo. If it's limescale these remedies stand a good chance of dissolving it. If it's the salt/rust concretion that comes from using a marine engine in salt water then maybe it's not such a promising idea.
 
If your engine/ heat exchanger has a zinc anode ( mine does) , be sure to remove it before introducing hydrochloric acid; it will sure be gone if you don't, zinc reacts quite vigorously with even fairly weak solutions of hydrochloric acid.

Graham
 
Muriatic acid is merely an old name for hydrochloic acid.

It is a solution of hydrogen chloride, a gas, in water.

You should check the concentration of any muriatic or hydrochloric acid you buy as it is avaialble in a wide range of concentrations.

Ordinary laboratory "concentrated" hydrochloric acid is approx 36% by weight of HCl.
Higher concentrations are, for obvious reasons, called fuming hydrochloric acid. 40% is the most concentrated generally available.

I dont know what Kelly's eye is calling "pure hydrochloric acid" No such thing really apart from hydrogen chloride gas, as there are only solutions in water up to the concentration figures above.

As for "it's lethal if you get even a small splash on you" Well I am still alive! So a bit of an exaggeration perhaps
But remember if using it in the marine environment it is lethal to fish from 25 mg/l up and generally toxic for aquatic organisms due to pH shift.


Yes, I wish people would stop distinguishing muriatic and hydrochloric acids - they are just different names for the exact same thing. Both are aqueous solutions of the gas HCl. Muriatic acid is the older name, pre-dating knowledge of its composition; hydrochloric acid is the newer, more systematic name (newer as in 19th century not 18th!). But they are the same thing, with the same properties.

However, the "one splash" bit - I wonder if he's getting confused with hydrofluoric acid, which is indeed extremely toxic, and can kill from a splash on the skin? However, there is no way that hydrofluoric acid would be encountered outside a laboratory, industrial chemical plant or perhaps a glass engravers. Though I do recall an episode of "Casualty" where a tanker transporting it (it is used industrially) spilled a lot on the road, with nasty consequences for the first responders.
 
Muriatic acid is the older name, pre-dating knowledge of its composition...

And like many antiquated terms, still in use in the USA.

That may sound bitter, but I'm currently struggling though a Nigel Calder book on refrigeration that is written (as they all seem to be) for the US market. Pints (and not even proper ones), pounds, Fahrenheit, BTU, inches, PSI - it's doing my head in!
 
>As for "it's lethal if you get even a small splash on you" Well I am still alive! So a bit of an exaggeration perhaps

I've seen the scarred face of somebody who had their face covered with Hydrochloric acid when a Chemistry experiment went wrong. Muriatic acid wouldn't scar a face because it's so diluted.

Muriatic acid is hydrochloric acid It is just an old name

It is as hazardous as hydrochloric acid It the same stuff, not necessarily more dilute.

Using an old name wont make it any less hazardous.

I cannot comment on the experiment that went wrong because I don't know what the experiment was.
Some short comings there somewhere in the risk assessment and safety precautions taken for that to happen.
 
Pints (and not even proper ones), pounds, Fahrenheit, BTU, inches, PSI - it's doing my head in!
and they still expect us to believe they really landed on the moon! :D
 
It may be an urban myth (note to self: check on Snopes) but didn't a Mars lander crash because the European design team were using mm, and the US inches?

I though that was the cause of the big problems with the Hubble telescope ?
 
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