15.2 Trouble Shooting (Engine)
DETROIT DIESEL 53
and therefore has a concave meniscus. A mercury column is read by sighting horizontally between the top of the convex
mercury surface (Fig. 2) and the scale. A water manometer is read by sighting horizontally between the bottom of the
concave water surface and the scale.
Should one column of fluid travel further than the other column, due to minor variations in the inside diameter of the tube
or to the pressure imposed, the accuracy of the reading obtained is not impaired.
Fig. 2 - Comparison of Column Height for Mercury and Water Manometers
Refer to Table 3 to convert the manometer reading into other units of measurement.