Motoring Notes
Decarbonizing the Morris
" Suet' a bore, we're without the Morris ; she's gone to be decarbonized and won't be back for a week."----HoW often does one hear such a remark ! People waste days and weeks of their cars, often putting themselves to con- siderable inconvenience and expense, when they might so easily tackle the job themselves.
Decarbonizing can be done for nothing in three hours. No extra tools are required. The process is simplicity itself.
First let the water out of the radiator until it is below the level of the top of the cylinders, next remove the top of the bonnet by unscrewing the single nut. that holds it in place. It is most. important to have some clean gritless Place on which to arrange all the nuts, &c., which are taken off during the operation and to lay them out in their order so as to be sure of putting each nut back on its own bolt, for the very best of them will vary slightly.
Undo the water joint attachment and slip the pipe upwards until it is clear of the cylinder head ; slack off the fan nut and lower it out of the way, remove all the plugs, laying them out in order, and see that the points are clean and ha% e a suitable gap. Loosen the nut holding the oil pump pipe so that the pipe can be lifted.
Now unscrew the nuts in the detachable head, not ing carefully those which hold the ignition wire attachment, the electric horn and the oil pipe holders. When the head is loose and everything is clear, stand on the chassis, straddling the engine, and carefully raise the engine-bead. It will not be possible to lift it out completely in this position, as the arms are one each side of the bar of the top of the bonnet, but it can be raised so far that it will rest on the top of the studs. whence it can be easily lifted off from the side.
Having got the detachable head out, turn it upsidc-rlown on the bench and serape off all hard carbon found adhering in the compression spaces. Great care should be taken that the flat surface which beds on the gasket is not scored by the implement used to remove the carbon. Brush off all loosened carbon and see that everything is perfectly clean before attacking the tops of the pistons themselves. When doing the pistons even more care must be taken not to let the tool used for decarbonizing slip so as to scratch Or prise up the gasket. Plug up all holes in the water jacket with cotton waste, then raise each piston as required and see that its valves are closed. It sometimes happens that the carbon is so hard that it has to be chipped off ; the best tool to use in this ease is a very narrow screw driver and the lightest of small mallets, but in the ordinary way. howeveri any tool which will scrape will do.
Having removed all the cotton waste, support the head on the studs as was done while it was being removed, and while it is in this position make yet another inspection to see that there is nothing in the shape of grit or carbon to be seen, then lower it carefully into place and the worst of the job is done.
Put a drop of oil on each stud before putting back the nuts, and do not tighten any of them up straight away as this throws considerable strain on the ones which are not yet tightened, but go over them all several times until all are thoroughly tight. Reinsert the plugs and refix the water joint ; readjust the fan and fill up with water. Put the oil pipe back in place and tighten its nut ; run the engine until warm and then tighten up the nuts again.
It often happens that after decarbonizing the eompress' is poor. This rights itself almost immediately as it is caused by small pieces of carbon which, having escaped the vigilance of the " decarlxmator," have got under the valves and pre- vented their closing. When the car is decarbonized at home a gasket lasts the ear's whole life if care is taken, but, unless the garage is an exceptional one, it new gasket becomes almost a matter of course every time the car is decarbonized.
HONOR GOODDART.
The Motoring Editor will be glad to answer questions or draw up itineraries for readers.
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