POROUS INNER TUBES

Evening Star, Issue 21945, 4 February 1935, Page 6

POROUS INNER TUBES

AMMONIA SOLUTION TREATMENT • After prolonged service the inner tubes of tyres frequently become porous and allow the air pressure gradually to fall. It is advised by tyre companies that the inner tubes should be renewed whenever the old casings are replaced. The following method of renovating old and porous tubes was published in ‘ Motor Transport,’ a prominent British commercial motor journal, but it must be distinctly understood that this hint is not given with any warranty as to its value. It is stated that tyre tubes become porous because of the formation, of acids in the rubber, especially where they have been exposed unused to the air for a long time, and that a solution of ammonia, water, and French chalk will neutralise these acids. The process recommended is to take three .tablespoons of diluted ammonia, and mix the liquid thoroughly with a tablespoon of French chalk. The mixture should then be introduced into the inner tube by means of a fountain-pen filler. If the tube is not, to be used immediately, inflate it to the pressure of a rubber ball ami coil it so that the mixture may circulate freely inside. The tube should also be washed with the solution on the outside. This ammonia, compound, it is said, not affect the tyre, and will not work itself under existing patches, but will seal small punctures for several days anti and prevent the tube from becoming still more porous.