TM  10-3930-638-24&P 4-2.   ENGINE   MAINTENANCE   (cont) a. Cylinder Block Assembly (cont). STEP LOCATION ITEM ACTION REMARKS CLEANING WARNING Wear safety glasses when drying parts with compressed air. Fail- ure to do so could cause serious injury to eyes and possible blind- ness. If you hurt your eyes or if a foreign object is blown into your eyes, seek medical attention immediately. 5 Cylinder  block  (19) Clean Clean cylinder and crankcase oil passages thoroughly using moisture-free com- pressed air and brass wire probe. Clean exterior with live steam. Clean upper and lower  cylinder  grooves,  oil  galleries  and drain openings thoroughly. Clean cam- shaft bushing bores thoroughly. Use 0.020 inch wire to clean camshaft bush- ing bore jets. Dry thoroughly with mois- ture free compressed air. WARNING Dry cleaning solvent (P-D-680), used to clean parts is toxic and flammable.  Wear  protective  goggles  and  gloves  and  use  only  in  a well ventilated area. Avoid contact with skin, eyes, and clothes and don’t breathe vapors. Do not use near open flame or exces- sive heat and don’t smoke when using it. Failure to do so could cause serious injury. If you become dizzy while using cleaning solvent, get fresh air immediately, and get medical attention. If contact with skin or clothes is made, flush with large amounts of water. If contact with eyes is made, wash eyes with water immedi- ately,  and  obtain  medical  aid  immediately, 6 Cylinder  sleeves  (1) Clean Use cleaning solvent P-D-680. Dry thor- oughly with moisture free compressed air or clean cloths 7 AIl other parts Clean Immerse in cleaning solvent P-D-680. Dry thoroughly with moisture free compressed INSPECTION air or clean cloths 8 Cylinder block (19) a. Inspect Replace if cracked, damaged, worn, eroded, or distorted or if grooves and lands pitted or eroded b. Measure top Use straight edge and feeler gauge. If sur- surface face  varies  more  than  0.002  inch  replace block 4-5