I thought I'd have a look behind the water branch on the block I'm going to be using for my spare engine. Just wee bit restricted then...

Location: Moist and warm Hertfordshire

More limestone than a Derbyshire quarry!!

Ian Mc.

Location: Shropshire

Years ago there was a similar photo from the Essex A7 Club, though it showed the whole are clogged up - there had been an over heating problem, the owner investigated and ..... :-(

Once you've cleared that lot away try and clean the areas between the cylinders too, and if you've plenty of time and you can get core plugs to stay in, take out the existing core plugs all round (including the head) and have a really good go at it. You will be surprised/dismayed at the quantity of grot/muck that comes out.

Location: Very edge of Europe - West

Soak it in Oxalic Acid for a week.

Will come out grey and im imaculate. The acid goes green.

when I use and have finished with it, I pour the leftovers down the bath. Its ace at cleaning out the plughole

This is a question, NOT a suggestion!

Today I bought oxalic acid, in powder form, from my local builders merchant. Would a solution of this work to dissolve the lime without damaging the block?

I am going to use it to clean staining from fiberglass yacht hulls. Proprietary "hull cleaner" is a solution of oxalic acid at £15 for .5l, a tub of crystals which will make up gallons of hull cleaner cost me £7.00. I know the hull cleaner dissolves lime as it fizzes like mad if I spill any on the ground. It will remove rust staining so Im not sure how safe it is to use on an iron block.

Stuart.

Edit, once again my slow typing results in a crossing of threads....

Location: Devon

Location: Devon

Not sure, I think twice the amount of powder the guff on the tub of powder says.

I think its better stuff than phosphoric acid as the steel comes out grey like it has been shot blasted.

I decided to experiment with a bit of rusty steel Dad just cut out of the chummy floor. Its in Oxalic acid solution of about a table spoon to 1/2 a pint of water.

Here is the starting point.

https://www.facebook.com/photo.php?fbid=559071960831005&l=8fa45cbbe3

Watch this space for the result!

Location: Devon

Good thinking, Stuart. Whilst you are playing, it might be useful to know what it does to copper(head gasket) brass(rad.core) and aluminium (water manifolds)??

Ian Mc.

Location: Shropshire

Yes Ian, I was thinking the same. My wife seems to have given her mother all our jars for filling with home made jam, so I will have to do one metal at a time.

The water has gone a light lime green colour already, its only been in there an hour.

Anyway, off to try it on our boat, before setting about a customers pride and joy with an unknown strength acid!

Stuart.

Location: Devon

Stuart

It works on even the most scaly scabby rusty steel.

I bought a second hand towbar for the pug off e-bay, fair play it came with all the nuts and bols etx, but by Jezus they were rusty.

I didnt fancy a couple of hours with the cup brush in the angle grinder so soaked them in oxalic acid for a few days.

The areas of surface rust went grey very soon. But even the scabby bits were eatn off by the time it was finished.

after a soaking I give everything a clean in the bath (I have an enamel bath) first, then straightaway a doo in the dishwasher on top temp, before being dried in the oven. That way you are sure of cleanliness and if the piece stays hot it doesn't rust again.

However for cast iron, a skin of oxide is a good thing.

I found another jar, that one has an aluminum pop rivet it now, that should test for electrolytic action too.

I will put a copper elbow with a soldered join it next, that should cover all the bases!

I know from using it on boats, that there seems to be no effect on bronze skin fittings.

Location: Devon

Stuart,
What was the product name that you used, have ben to my local builders and can only find brick cleaner but that has Hydrochloric acid.
Thanks

Location: Basingstoke

Derek, Oxalic acid is widely available on eBay
Regards Ian. 😊

Derek,

Also available here, but note 'Not for sale to the general public'.

http://mistralni.co.uk/products/oxalic-acid-dihydrate?gclid=CNelvNXsoroCFfHKtAodPS0AIw

Jeff.

Location: Almost but not quite, the far North East of England

% days in, the steel has produced a lot of white sludge and the acid has turned the colour of lime cordial. The aluminum pop rivet fizzed a lot to start with, I guess due to dissimilar metals. However the rivet part seems pretty much untouched although the zink plating on the steel pin has discolored. I'l try to get some pictures tomorrow.

Derek, there is no brand name, its in a plain white tub, I guess there is a makers name on it, however I have left it on the boat, so will have to check when Im next down there.

Its doing a cracking job on removing brown river staining from white fiber glass. Its also sorted out some black water staining on internal wood work in my boat. Good stuff!

Stuart.

Location: Devon

Stuart

Furniture restorers use it for removing stains in wood.

The results after 2 weeks in Oxalic acid, the very rusty steel has not been dissolved although there isnt much rust left on it. The pop rivet has been eaten away a little bit on the thinnest edge, but not an alarming amount.

I would be quite happy to try this method of descaling a block, although Im not so sure about putting it in a complete cooling system, as the electrolytic action was quite dramatic on the pop rivet.

Here are links to the pictures.

https://www.facebook.com/photo.php?fbid=566096430128558&l=be6a3c8fa5

https://www.facebook.com/photo.php?fbid=566096363461898&l=d2a21dda70

All the best

Stuart.

Location: Devon

Those links should work now, sorry, somehow the pictures got set to "friends only" on Face Book.

Location: Devon

Some time ago on this forum, Hedd was extolling the virtues of http://www.heritagesteamsupplies.co.uk/Z-Heritage-Steam-Supplies/Descalers/p-297-982 this stuff. It sounds ideal.

Has anyone any hands on experience of using it pse.??

Ian Mc.

Location: Shropshire

Some years ago my father in law had to have some old machinery removed from his company's site,the feet were anchored down with seized bolts to the floor.One of the dismantling team poured Coka-Cola onto them & left over the weekend.They were un-seized on the Monday without too much effort.Coke contains Phosphoric acid,if it can do this God only knows what it does to ones insides.

Location: Piddle valley, Dorchester