The block can be cleaned with standard parts cleaning equipment. However, if the crankcase and bores are heavily coated with varnish, gum, carbon, sludge, or rust deposits in the coolant passages, hot tanking will be necessary.
Clean out all oil galleys and water passages with wire brushes designed for this purpose.
WARNING: The cam bearings (Figure 2-100) must be replaced if the block is “hot tanked”. The caustic solution used for this type of cleaning, will etch and weaken bearing surfaces. The expansion plugs and oil filter pressure regulating valve must also be removed before hot tank cleaning.
Coat the block with a light solvent after cleaning to prevent rust formation. Useful solvents are available from LPS Corp., Solder Seal, WD-40 and similar firms.
NOTE: Be sure to inspect the piston cooling oil tubes in turbo diesel blocks. Verify that the tubes are clear (Figure 2-101).