DETECTING A LEAK

Sun (Auckland), Volume 1, Issue 142, 6 September 1927, Page 6

DETECTING A LEAK

THAT CARBURETTOR FLOAT. HINT FOR OWNER-DRIVERS. The float mechanism of the carburettor which keeps the spirit ready for use at a level just below the exit from the jet is a device which sometimes needs adjustment. The float, generally a thin spun-brass closet! cylinder, may need adjustment. In the old days—but very seldom now—the float became punctured. How this happened was a great mystery to the average motorist But it is generally due to some foreign matter in the sheet of metal while it was being rolled, and from which the two halves of the float were stamped or spun. This foreign matter might remain in position indefinitely, or it might by the constant jumping about of the float in the float chamber become dislodged, leaving a tiny pinhole in the float through which the spirit gradually—very gradually—leaked, thus increasing the weight of the float and causing the level in the float chamber —and in the jet to correspond—to rise so that petrol flowed out of the jet. The trouble came on gradually. The cause was suspected when the float (which should, of course, be empty), was shaken near the ear. The petrol in the float made a sound like shaken sand—a sure indication of petrol in the float. If flooding of the carburettor continues, due to too high level, and the float is found to have petrol in it, the remedy is to remove the petrol’ and solder up the hole. The hole is so small that it cannot be seen by the naked eye, also the petrol oozes through so slowly that it evaporates as it comes through, so that nothing is showing, and the location of the leak is difficult. The old method of finding out the nole or puncture is still the best. The float should be submerged in hot water. The heat vaporises any petrol in the float, sets up an internal pressure, and the resultant petrol gas bubbles through •he hole and up through the water The location of the hole is thus simple’ ’he float should be kept submerged in the warm water till all bubbling ceases It will then be clear of petrol, which will have all been evaporated and forced Tirough the leak. The float should be dried and allowed to rest, so that it can become filled with air again at atmosohenc pressure. Then the hole should rnos t carefully soldered up with soft io!der, using a small soldering iron and icraping away the superfluous solder, so is not to increase the weight of the float.

Insurance figures show that of 20,000,000 motor vehicle owners in lie United States, 16,000,000 carry some form of insurance, but only 4,000,000 carry liability insurance.