Hydrocchloric Acid Cleaning

[Little Dorrit]

Now I have to decide who to believe..I am sure you are all right..to varying degrees!

Don't feel any the wiser but a guess it was never a " 'its ok' or ' its not ok' " question

 

[VicS]

Now I have to decide who to believe..I am sure you are all right..to varying degrees!

Don't feel any the wiser but a guess it was never a " 'its ok' or ' its not ok' " question

I'd follow the advice of a qualified chemist if I were you

 

[RobBrown]

Or you could try Fernox!

 

[GrahamHR]

.......and all qualified chemists use the contrived SI system in terms of units rather than the contrived Imperial ones; I thinik not Both are arbitrary !

 

[VicS]

Or you could try Fernox!

Fernox is brand name.. including everything from water treatment cleaners and inhibitors to solders and fluxes. There’s specialist equipment such as powerflushing machines and scale reducers, plus renewable technologies including heat transfer fluids and underfloor corrosion inhibitors. Fernox also produces some quick-fix products for emergency repairs.

Fernox DS3, a sulphamic acid based descaler, was what I suggested on the OPs previous thread (q.v.) on the same subject
That will be good for removing carbonate scale

If the main problem is iron oxides then Fernox DS40 may be more effective. It is organic acid based . Citric acid I think

 

[Iliade]

Just to throw a spanner in the works: Marine engine's water systems tend to suffer from rusting, rather than limescale. I have been recommended phosporic acid as this is less inclined to eat the substrate. It will remove limescale too!

To be found in low concentrations in cola - fairly safe on iron engines, though not Beta's by the sound of it.

Some motors are held together by rust and chemical removal of the rust will expose major issues with the cooling system (perforated cylinder blocks etc) so do it with your eyes open... (but your safety glasses on :0)

At the end of the day, get a fresh water cooled motor and keep the good quality antifreeze topped up (as it contains/is a rust inhibitor)

 

[RobBrown]

Yes DS3 was what I used on my Bukh 20 manifold & separately on my old outboard. Really effective on the former in particular. Just purchased a bag from Homebase, sold as Central Heating/Boiler descaler. Best used warm/hot, so seems well suited for flushing through a running engine.

 

[pappaecho]

The best cleaners for any device needing descaling are organic acids like citric, tartaric and suphamic acids. These do not attack metals as such but their salts. Citric acid for example chelates iron oxides (rust) forming ferric citrate which is water soluble, and so just flushes away.
Citric and Sulphamic acids are extensively used for industrial boiler cleaner and metal fihinshing
Citric acid can be bought from Wine Making Shops. It is a food quality product and wont damage you or your engine, and a few drops in your gin and tonic tastes like lemon, which is nearly what it is

 

[VicS]

The best cleaners for any device needing descaling are organic acids like citric, tartaric and suphamic acids.

Sulphamic acid I guess you mean but what definition of "organic acids" includes sulphamic acid?

 

[poultey]

As said above, HCl will clean out limescale and not have much effect on the metal of the engine, other than removing oxides perhaps.
In the galvanzing industry, thousands of tonnes of steel are immersed in HCl of strength between 3 and 18% for typically 2-6 hours without any discernable effect.
Its also possible to get a metal inhibitor to add, so that leaving the acid for days at a time is possible. But you don't need that for this job.
Its a time and concentration issue. If the acid is so strong as to fume and be difficult to use, then maybe too strong.
If you leave it there for hours, then too long.
But weak strength for 10-20 mins, no problem.

I have plenty of HCL at 39% that I can comfirm fumes mightily. To create a solution for a 10 minute soak, extrapolating from your 'between 3 and 18%' comment, perhaps a 3:1 water to HCL would be 'safe' ?

 

[poultey]

Dilute hydrochloric acid has very little effect on iron/steel and it is perfectly safe to use it in most engines. Remove the thermostat and anodes. Diluting it excessively will remove the effects you are trying to achieve - you cannot buy it in a concentrated state. Buy HCl based brick cleaner (there are other types) from a builders merchant and use it as it is. No reason to leave it for a long time, it will do its job in about 10 minutes.

Rydlyme is often recommended for the job although I have never used it. I have used hydrochloric acid several times, very successfully, in engines and in toilets.

I have plenty of HCL at 39%. To create a solution for a 10 minute soak, perhaps a 3:1 water to HCL would be 'safe' ?

 

[vyv_cox]

I have plenty of HCL at 39%. To create a solution for a 10 minute soak, perhaps a 3:1 water to HCL would be 'safe' ?

The acid sold in supermarkets throughout Europe for domestic use is usually about 20%, around 4:1. Something like 6 or 7% w/w. Perfectly adequate for scale removal and does no damage to metals, rubber or plastic.

 

[Fantasie 19]

I love the way a 14 year old thread just lurches into life again..