Tips on gland packing

Tips on fitting gland packing

The water pump contains two sealing glands which are rings of special sealing material each of which is sandwiched between a pair of angled faces. These act to compress the sealing material on to the shaft to make an effective seal. On the majority of cars manufactured after 1930 the gland rings are separated by a spring-loaded telescopic 'lantern ring'. On earlier cars the lantern ring was a solid one-piece item.

The gland packing that we offer is supplied in two straight lengths. One is of a slightly thicker cross-section than the other. To form the gland ring the material should be wrapped tight around the pump spindle such that the free ends lie side by side. Using a sharp blade the free ends are cut off at an angle, such that the two cut ends overlap. When fitted the angled faces will overlap and lie one on the other, making a scarf joint. A gland ring should be made from each of the lengths of material.

When assembling the pump the first gland ring to be fitted should be the one made from the thicker section material. It will be necessary to reduce the radial thick ness of the ring by squeezing it. It is fairly soft, and squeezing it between the fingers should be adequate. This is then followed by the lantern ring arrangement followed by the second thinner gland packing.

Note that in the case of the spring-loaded lantern ring it is important to fit the outer part in to the pump body first. If this is reversed it will inhibit the flow of grease.

The knurled nut on the forward end of the pump body should never be more than hand tight. If over-tightened too much pressure may be put on the gland packings. The friction generated will cause the grease within the shaft to liquefy and may cause the shaft to overheat. We have seen them blue with heat!