5-43. CYLINDER BLOCK-MAINTENANCE INSTRUCTIONS (Continued).
After the cylinder block has been cleaned, it must be pressure tested for cracks or
leaks by either one of two methods.
(a) This method may be used when a large enough water tankis available and the
cylinder block is completely stripped of all parts.
(1) Seal off the water inlet and outlet holes air tight. This can be done by using steel
plates and suitable rubber gaskets held in place by bolts. Drill and tap one cover
plate to provide a connection for an air line.
(2) Immerse the block for twenty minutes in a tank of water heated to 180-200F
(3) Apply 40 psi (275.8 kPa) air pressure to the water jacket and observe the water in
the tank for bubbles which indicate the presence of cracks or leaks in the block. A
cracked cylinder block must be replaced by a new block.
Wear protective eye goggles when using compressed air.
(4) After the pressure test is completed, remove the block from the water tank. Then
remove the plates and gaskets and dry the block with com- pressed air.
b. This method may be used when a large tank is unavailable, or when it is desired
to check the block for cracks without removing the enginefrom the equipment
which it powers. However, it is necessary to remove the cylinder heads, blower, oil
cooler, air box covers and oil pan.