Pre-WW1 Davison oil sight glass gaskets
Part No. 69-462
There are two sizes of gaskets required for the 3+1/4inch Pre-WW1 Davison sight glass. A 31mm OD gasket to fit in the top cap and a 29mm OD gasket to fit on the base of the glass.
One Top gasket and one Base gasket should be installed.
There are two different sizes of glass—to check that yours is the more usual size that these gaskets are suitable for check the ID of the screw- on cap is 31mm.
In the kit there are 2mm and 3mm thick gaskets (4 gaskets in total) Depending on the thread lengths on your pump then you might find that either the 2mm or the 3mm is more suitable or even a mixture of a 2mm and a 3mm. thick gasket
Initial gasket compression -After installation tighten up and leave the unit alone for 2 hours. Then Tweak tighten. After a further 10 to 24hours have elapsed then Tweak tighten again—now run the pump