TM 9-2815-225-34&P 3-42.  OIL COOLER REPAIR (Contd) LOCATION/ITEM ACTION REMARKS b.  Cleaning WARNING   Compressed  air  used  for  cleaning  purposes  will  not  exceed  30  psi  (207  kPa).    Use  only with effective chip guarding and protective equipment such as goggles or shield, gloves, etc.  Failure to comply may result in injury to personnel.   Approved solvents may be flammable and will not be used near open flame.  Use only in well-ventilated area.  Failure to comply may result in injury to personnel. NOTE Cleaning  procedures  for  the  oil  cooler  assembly  are  the  same  for  M915/Big  Cam  I  and M915A1/Big Cam III.  M915/Big Cam I is shown. 17. Housing (12) Clean lubricating oil and Use compressed air. contaminants by forcing solvent SD-3 through oil ports in reverse direction of normal flow. 18. Filter element (6) a.  Immerse in solvent SD-3 and Force solvent around tubes and let stand for several minutes. clean using compressed air. b.  After cleaning, flush thoroughly with hot water. c.  Prepare solution containing one part muriatic acid and nine parts water.  Add 1 lb (0.454 Kg) oxalic acid and 1.28 fl.  oz.  (37.85 ml) pyridene to each 5 gal.  (18.9 L) of muriatic acid. d.  Immerse in solution. e.  Remove when foaming and Reaction normally stops in 30 to bubbling stops. 60 seconds. f.  Immerse in 5 percent solution of sodium carbonate. g.  Remove when bubbling stops. Flush inside of tubes with light Pressure-flush with clean, warm oil after both oil and water sides water. of cooler core are clean and dry. 19. All other parts Clean. Refer to para. 3-6 for cleaning instructions. 3-224