TM  10-3930-638-24&P 4-2.   ENGINE   MAINTENANCE   (cont) b.  Cylinder  Head  and  Valves  (cont). STEP LOCATION ITEM ACTION REMARKS REMOVAL 1 Cylinder  head a.  Valve  spring  (3) Compress Use valve spring compressor tool (8), top b. Two valve keepers (1) Remove  and  discard c. Valve spring (3) Release Carefully release pressure on valve spring  compressor  tool d. Spring retainer (2) Remove e. Valve spring (3) Remove f. Spring seat (4) Remove g. Valve stem seal (5) Remove NOTE Identify (number) valves (6 and 7) and respective bores for reference  during  installation. 2 Cylinder  head a. Exhaust valve (6) Remove (8), bottom b. Intake valve (7) Remove CLEANING CAUTION In following step be careful not to scratch valve stems. 3 Four exhaust valves (6) Clean Use fine power driven wire brush and intake valves (7) 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. 4-10