45 CYLINDER HEAD 44 HARDENED INSERT VALVE NX 1 Fig 85 Relation of Valve and Seat Angles NOTE Be careful when replacing sleeves They are installed in the cylinder head with a press fit and must be started into place true with the exhaust bore in the cylinder head NOTE Sleeves are available in standard 002 and 010 oversize for service 4 Place sleeves in a container of dry ice solidified carbon dioxide for about 10 minutes 5 Warm cylinder head to about 200 F support cylinder head to avoid damage to cooling fins CAUTION Do not use an open flame 6 Remove sleeves one at a time from dry ice and tap into place with a soft tool NOTE Do not damage exhaust manifold end of sleeves they are a press fit into the exhaust manifold F Fig 86 Removing Exhaust Manifold Sleeves p r Fig 87 Reaming Valve Guide Valve Guides Reaming Oversize W 1 1 utilized obtain proper 1 to guide clearance in all cases except when the guide is either cracked or is worn to the extent that reaming will not clean up the guide bore to permit use of the largest oversize valve available standard diameter W and 02011 stems 1 Select from the reamers listed below the smallest diameter oversize reamer that will provide proper refinish of the guide bore I m 1 0 00 ersize valve Reamer J 5830 5 use for 02011 oversize valve NOTE Reamers listed above are included in Hand Reamer Set J 5830 2 Ream bore of valve guide starting at the combustion chamber side fig 87 and flush with cutting oil to avoid scoring Do not force or withdraw reamer 1 reaming operation Reamer should completely letely through bore and be removed at the valve spring side of the cylinder head Wipe refinished bore to remove cutting oil and chips inspect bore 3 Inspect valve seat and reface as necessary to obtain correct seat angle and concentricity with guide bore 4 Select and use valve in same nominal oversize as that of reamer last used in refinishing the guide Valve Guides Replacement guides n turbocharged engine available 1 except oversizes of 00211 replacement standard 01011 and 020 The service guides are bored to permit use of valves with standard diameter stems Remove guides the J 21280 Remover hammer minimum Drive valve guide from the spring seat side fig 88 so that the guide will exit the combustion chamber side the cylinder CORVAR SHOP MANUAL