What to use for cleaning radiators...?

[James P]

I've never had a radiator that needed internal cleaning before (as far as I know ), so what to use?

I found some stuff in a local Repco or AutoOne (can't remember which) which was the only such product on offer, so I bought it. When I actually read the instructions (doh!), it is supposed to be mixed at 5% with water, put into the cooling system and left in there for 20 minutes with the engine running. This is no good to me, as the radiator is off the bike (and the bike itself is still in many bits ).
As a compromise, I mixed it at 50% with water at about 60 degrees C, poured it into the radiator and left it for 20 minutes. It was fizzing away, so I presumed that it was doing something. However, on emptying the radiator and flushing it with hot water, it seemed that there were even more scale deposits than before .

I managed to get a nylon brush into the top tank of the radiator and a few strokes saw the scale deposits disappear. Unfortunately, there are more scale deposits in the bottom tank and in the two cooling tubes I can see through the filler hole, so I presume the other cooling tubes are in a similar state.

Can anyone recommend a locally-available product to clean out this radiator properly?

While I wait for a reply, I'll start straightening all the bent cooling fins...

Thanks & regards,
James

[pkay]

I bought a product from Bunnings some time ago that was a scale remover for metal surfaces including kettles and stuff. Can't remember the name but if does a kettle element if would be OK for your radiator. It was in a white bottle.......

[BRG1200]

De-scaler? For dishwashers and kettles. comes in powdered form

[James P]

Thanks Pkay & BRG. I presume these products are OK for use on aluminium? I will head to Bunnings and have a look what they've got.

Thanks again & regards,
James

[BRG1200]

Just don't ever use Oven Cleaner! Unless you like watching aluminium dissolve of course ;-)

[James P]

On checking the shelves at Bunnings, I found a variety of descaling products. However, many of them warned that they were unsuitable for use on aluminium. The one I chose (http://www.hillmark.com.au/Products/Scalex.aspx) stated "Avoid prolonged contact with aluminium, brass & copper", so I reasoned that it should be suitable if not left too long.

The suggested strength was one tablespoon (15ml) of descaler per litre of hot water. My radiator volume was a only a little over 400ml, so I used a Half Tablespoon of descaler in about 450ml of hot water. The suggested soaking time was five minutes, but by the time I'd finished faffing about with something else, the solution had been in the radiator for almost ten minutes. The solution was clear when mixed and came out cloudy at the end, so at least some of the scale had been removed.
After a flush with hot water, I inspected the interior of the radiator (at least the parts I could see) and almost all traces of scale had disappeared. In order to make sure that any remaining scale was removed, I repeated the process, this time using about 12ml of descaler in about 450ml of hot water, left for ten minutes.
The solution came out only very slightly cloudy after the second attempt. After another flush, I couldn't see any more obvious traces of scale, so the operation appears to have been a success.

I would probably have investigated descalers eventually, but many thanks to those who responded - it shortened my dithering time considerably!

Regards,
James

[L.B.]

Could you be thinking of CLR brand?