Before removing cylinder liners for block cleaning, the liner bores should be gaged to determine whether liner replacement is necessary. Refer to section 1.23.2.2.
Remove cylinder liners with the cylinder liner removal tool (J–45876) before putting the block in cleaning or descaling baths, to avoid trapping cleaning agents in block liner seating bores. See Figure 1-8.
After disassembling and before removing the cylinder block from the overhaul stand for cleaning and inspection, install the two metric eye bolts (J–35595) to the cylinder block. See Figure 1-9.
Clean the cylinder block as follows:
1. Remove all oil and water gallery and weep hole plugs to allow the cleaning solution to enter the inside of the oil and water passages. On current block, remove bolt-on plate or piston-cooling oil spray nozzle at the base of each cylinder bore.
2. Immerse and agitate the block in a hot bath of a commercial, heavy-duty alkaline solution.
3. Wash the block in hot water or steam clean it to remove the alkaline solution.
4. If the water jackets are heavily scaled, proceed as follows:
[a] Immerse and agitate the block in a bath of inhibited phosphoric acid.
[b] Allow the block to remain in the acid bath until the bubbling action stops (approximately 30 minutes).
[c] Lift the block, drain it and immerse it again in the same acid solution for 10 more minutes. Repeat until all scale is removed from the water jacket area.
[d] Rinse the block in clear, hot water to remove the acid solution.
[e] Neutralize the acid that may cling to the casting by immersing the block in an alkaline bath.
[f] Wash the block in clean water or steam clean it.
5.Dry the cylinder block with compressed air. Blow out all of the bolt holes and passages with compressed air.
NOTE:
The above cleaning procedure may be used on all ordinary cast iron and steel parts for the engine. Aluminum parts, such as flywheel housing, air intake manifold, oil filter adaptor and the camshaft gear access cover should NOT be cleaned in this manner. Mention will be made of special procedures when necessary.
6. Be certain that all water passages and oil galleries have been thoroughly cleaned and dried.
Install weep hole plugs and precoated pipe plugs. Install new cup plugs using a coating of good grade non-hardening sealant such as Loctite® 620 or equivalent. Refer to section ADDITIONAL INFORMATION1.A, “Engine Plug and Dowel Chart.”
7. Pressure test the cylinder block. Two methods of cylinder block pressure testing may be used depending on the test facilities available:
[a] Immersion method; refer to section 1.1.3.1.
[b] Leak-marker method; refer to section 1.1.3.2.