Cleaning carbon from aluminium pistons and cylinder head

[RichardHawkins]

Along time ago, probably 20 years, I used a product called Metprep 450. This substance was excellent, but I cannot find it any longer. Can anyone recommend a product that will not damage the aluminium?

[hatman]

Coincidentally, this same subject was recently raised on the Norton Owners’ Club forum, one of the recommended treatments being to soak in boiling rhubarb juice. Claimed to be very effective and, if it matters to anyone, extremely eco-friendly to boot!

[summerinmaine]

@hatman

Coincidentally, this same subject was recently raised on the Norton Owners’ Club forum, one of the recommended treatments being to soak in boiling rhubarb juice. Claimed to be very effective and, if it matters to anyone, extremely eco-friendly to boot!

Probably similar to using Coca-Cola, which contains phosphoric acid. Here’s rhubarb juice:

@Wiki

Rhubarb leaves contain poisonous substances, including oxalic acid which is a nephrotoxic and corrosive acid that is present in many plants. The LD50 (median lethal dose) for pure oxalic acid in rats is about 375 mg/kg body weight,[15] or about 25 grams for a 65 kg (~140 lb) human. While the oxalic acid content of rhubarb leaves can vary, a typical value is about 0.5%,[16] so a rather unlikely 5 kg of the extremely sour leaves would have to be consumed to reach an LD50 of oxalic acid. Cooking the leaves with soda can make them more poisonous by producing soluble oxalates.[17] However, the leaves are believed to also contain an additional, unidentified toxin,[18] which might be an anthraquinone glycoside (also known as senna glycosides).[19]

In the petioles, the amount of oxalic acid is much lower, only about 2-2.5% of the total acidity.[20] This means that the raw stalks may not be hazardous, though they are generally thought to be in the US. The tart taste of raw stalks is so strong as to be unpalatable to many.

[ricarbo]

Last time i did this i used Redex petrol treatment as a solvent and a piece of hardwood as a scraper. Seemed very effective. Any one else tried this?
Richard

[JJDraper]

Last time I did a head gasket change I used acetone, sparingly, with a kitchen towel for the final clean of both cylinder head and block. It got the faces really clean and oil free. Gasket has been as good as gold ever since. Always use none ‘melty’ gloves and keep it off your hands - it does nasty things to the fats in your skin.

Acetone seems freely available from supermarkets for home use in France, not the UK! I always stock up when on holiday…

Jeremy

[mikealdren]

You can buy it by the gallon on Ebay, it’s good for cleaning up tools when using fibreglass resin.

Mike

[Lotus_fan]

I got all my acetone and fibreglass from these guys
resin-supplies.co.uk/intro_page.htm

I’m just a very happy customer