TM 55-1905-220-14-10
5-20. CYLINDER BLOCK - MAINTENANCE INSTRUCTIONS (Continued).
LOCATION
ITEM
ACTION
REMARKS
CLEANING
2.
a. Scrape all gasket material from the cylinder block.
Then remove all oil gallery plugs and core hole
plugs (except cup plugs) to allow the cleaning
solution to contact the inside of the oil and water
passages. This permits more efficient cleaning
and eliminates the possibility of the cleaning
solution attacking the aluminum core hole plug
gaskets (if used).
b. If a core hole plug is difficult to remove, hold a
3/4 inch drift against the plug and give it a few
sharp blows with a one pound hammer. With a 1/2
inch flexible handle and a short extension placed
in the countersunk hole in the plug, turn the plug
slightly in the direction of tightening. Then turn
it in the opposite direction and back the plug out.
c. Clean the cylinder block as follows:
(1)
Remove the grease by agitating the cylinder
block in a hot bath of commercial heavy-duty
alkaline solution.
(2)
Wash the block in hot water or steam clean it
to remove the alkaline solution.
(3)
If the water jackets are heavily scaled, proceed
as follows:
(a)
Agitate the block in a bath of inhibited
commercial pickling acid.
(b)
Allow the block to remain in the acid bath
until the bubbling stops (approximately 30
minutes).
(c)
Lift the block, drain it and reimmerse it
in the same acid solution for 10 minutes.
(d)
Repeat Step "(c)" until all scale is removed.
(e)
Rinse the block in clear hot water to remove
the acid solution.
5-360