Unorthodox Decarbonising

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Tue 30 Aug 2005 14:46
Unorthodox Decarbonising - Tim G
I came across this in a 1954 copy of Gadgets Annual by W. N. Shaw and thought I'd share it:

Not specifically recommended but worth a trial!
DECARBONISE WITH WATER
A TRY-ANYTHING-ONCE motorist has enormous faith in the following distinctly unorthodox method of decarbonising his car.
He first gets his engine really hot and then sets the slow-running adjustment so that the engine ticks over at the revolutions required to travel at about 20 miles per hour in top gear. He then pours ordinary tap water directly into the air intake of the carburettor and then sits down to gloat over the uneven way the engine begins to run. He contends that the said uneven running is entirely due to the action of the cold water on the hor cylinder head which causes the rapid evacuation of excess carbon through the exhaust pipe. He pours in about a pint or so of water. After this has done its task(!), he gets on with the next stage of his drastic tratment. That is to pour about a pint to a pint and a half of one of the well-known upper cylinder lubricants into the carburettor, but he shuts down the revolutions to about twice the normal rate of tick over. He injects this a little at a time, and occasionally revs up the engine. He contends - and many motorists would say quite rightly too - that this frees the valve stems and does other useful things to the engine. Want to try the plan? Alright, go ahead, but don't blame us if it doesn't work!


Has anyone else heard of any unconventional maintenance techniques?
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Tue 30 Aug 2005 15:29
Unorthodox Decarbonising - smokie
Sounds distinctly dodgy to me, I'll wait for a tech expert to comment.

However the key phrase, which applies to this posting as well as the original article, is "don't blame us if it doesn't work!".


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Tue 30 Aug 2005 19:03
Unorthodox Decarbonising - Tomo
The water idea I never heard of. Pouring upper cylinder lubricant, Redex for instance, into a running engine was usual, and indeed there was a proprietary fluid sold specifically for decarbonizing which operated similarly - I can't remember the name now, it will come to me. It was as well to take a run to the country, not only to warm the engine but, if you had niggly neighbours, because intense smoke came from the exhaust.

It did work, things could be quite shiny down the plug hole.

Perhaps an aluminium alloy head would not get hot enough.
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Tue 30 Aug 2005 22:35
Unorthodox Decarbonising - Another John H
From personal experience of a recent head gasket failure which slowly leaked coolant into one cylinder - I can say that the crown of the piston from that cylinder was so clean you could read the manufacturers markings on it, and the alloy combustion chamber was shiny.

How you might add a suitable quantity of water to achieve the desired result without doing any mischief is another matter.
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Wed 31 Aug 2005 02:51
Unorthodox Decarbonising - Pete M
A water-methanol 50/50 mix has been used in piston aircraft engines as a power boost. Water injection has also been used in turbine engines as a power boost. It works by cooling the intake air and so making it more dense. More density gives more air, so more fuel at the right ratio gives more power. Same reason for an intercooler in a super or turbocharged engine. Small amounts of water are not a problem in an engine combustion chamber, but regulating the flow is harder. The gains are also so small as to make it impracticable. Modern fuels, fuel injection and multigrade oils also produce far less carbon than in the days of the advice above.
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Thu 1 Sep 2005 09:55
Unorthodox Decarbonising - Another John H
Added a picture to

groups.msn.com/honestjohn - Pictures say a thousand words.....

which shows the head I refered to above.

The only "photoshop" treatment was to lift the black level a bit, as the cheap camera seems to black crush.
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