TM-9-2815-220-34 Direct Support Manual for AVDS-1790-2C and AVDS-1790-2D Engines Download
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Figure3·182. Renwt•ing or i11stal/i11y oil confro/ piston ring pa 11der spiing. removing compound, Specification MIL-C-25107. (Ord Type 1 ). WARNING Use goglcs, rubber gloves, and rubber apron when cleaning parts in cal'bon re- moving compound. Provide adequate ventilation. Avoid inhalation of fumes and skin contact. If compound is splashed on skin, flush with fresh wate1· and wash with alcohol. Alcohol containing 2 to 3 percent camphor is preferable. TM 9·2815-220-34 b. Scrape remaining carbon deposits from piston ring grooves with a scper 01· broken piston ring. Be carefu 1 not to sc..atch or gouge ring grooves and lands on piston. Clean oil drain holes and oil ring grooves in piston. Remove carbon from oil holes in ring grooves. Clean carbon from piston pins with crocus cloth dipped jn dry-cleaning solvent , (P-D-680, Type 11). U 3-65. Inspection NOTE lt is important that all pistons be the same size (oversize) and weight. a. Inspect the top of the piston for oversi ze and weight code identification stamps. Refer to figure 3-t 82. I for stamp ocations. NOTE Early pistons supplied as individual spare parts were not stamp ed to indicate weight. To insure that al l pi st ons used for replacement are properly matched by wei gh t , all uncoded pistons nst be weighed and code stamped before bei ng installed in an engine. lf the weight code is missing or not legible, weigh the piston and metal stamp the weight identifica- tion code at the location shown in figure 3-182.1, using 0.25 inch high characters in accon.fance with Table 3-9.3. Change 3 3·94.1