305 ENGINE ASSEMBLY GMC GROUP 0 207 GASKET Crankcase Front End Cover 77 78 All Blazer Jimmy 3799620 1 53 GASKET 4 8 2230A 0 213 SEAL Crankcaee Front End Cover y 77 78 All Blazer Jimmy I 4033199 1 4 65 SEAL 2 0 0 stamped 3980267 8 16625 0 219 POINTER Timing 77 78 All Blazer Jimmy 3991435 1 1 10 POINTER 8 2327L 0 289 HEAD Cylinder NOTE I When using 463374 or 464038 in place of 35874 1 or 463539 it will be necessary to measure from top of guide to valve spring seat exh only lf dimension is 75 use 6263796 valve spring damper asm free ht 1 91 lavender stripes lf dimension is 84 use 391 IOSB valve spring damper asm free ht 2 03 lt green stripes 77 78 C I Cab 77 78 G 1 Van 14019925 2 HEAD w studs Note 1 8 0570A 77 78 OKI 2 06 16 305 14038097 2 196 00 HEAD w studs Note 1 8 0570A 0 289 GASKET GASKET UNIT Cylinder Head NOTE 1 Unit consists of 2 Cylinder head gaskets 2 Valve rocker cover gaskets 2 Inlet manifold side gaskets 1 lnlet manifold front gasket 1 Inlet manifold rear gasket I Water outlet gasket 1 lgnition timer distributor gasket 2 Exhaust pipe packings and I6 Valve stem oil seals NOTE Z Unit consists of 2 Cylinder head gaskets 2 Valve rocker cover gaskets 2 Inlet manifold side gaskets 1 lnlet manifold front gasket I Inlet manifold rear gasket 1 Water nutlat gasket 1 Ignition timer distributor gasket and 16 Valve stem oil seals 77 78 All 305 462690 2 5 60 GASKET 8 0630A 77 C 1 Cab 77 G 1 Van 465259 1 30 75 GASKET UNIT Note 1 8 0630A 77 OK 1 2 Sub Blazer Jimmy 463673 I 31 75 GASKET UNIT Nate 2 8 0630A 78 O1 03 G1 305 474258 1 20 90 GASKET UNIT cyl hd 8 0830A 78 OKI 2 06 I6 305 474259 I 21 80 GASKET UNIT cyl hd 8 0630A 0 293 BOLT PIN Cylinder Head 77 78 All Blazer Jimmy 3704796 16 52 BOLT short 14 x 1 8 0600A 77 78 All Blazer Jimmy 3734594 14 55 BOLT long 14 x 3 8 0600A 77 78 All Blazer Jlmmy 3767468 4 52 BOLT medium 14 x 3 8 0600A 77 78 All Blazer Jimmy 585927 4 35 PIN dowel i 8 0659 r 0 296 VALVE Inlet GMC 8 07108 77 78 CI Cab 77 78 Gl Van 3989083 A R 10 25 VALVE std 8 07108 77 78 C1 Cab 77 78 G1 Van 3995684 A R 10 25 VALVE 003 0 S 8 07108 77 78 CI Cab 77 78 GI Van 3995685 A Fl 10 25 VALVE 015 0 5 8 07108 77 78 C1 Cab 77 78 G1 Van 14033020 A R 10 35 VALVE 030 0 8 8 07108 77 78 CK1 2 Sub Blazer Jimmy 3989088 A R N L VALVE std 8 07108 77 78 CK1 2 Sub Blazer Jimmy 3997749 A R 10 25 VALVE 003 0 S 8 07108 77 78 CKI 2 Sub Blazer Jimmy 3997750 A R 10 25 VALVE 015 0 5 8 07108 77 78 CK1 2 Sub Blazer Jimmy 3997751 A R 10 25 VALVE 030 0 5 8 07108 0 297 VALVE Exhaust GMC 8 07008 77 78 C1 Cab 77 78 G1 Van 329275 A R 11 80 VALVE std 8 07008 77 78 C1 Cab 77 78 G1 Van 3995602 A R 11 95 VALVE 003 0 5 8 07008 77 78 C1 Cab 77 78 G1 Van 3995603 A R 1 1 95 VALVE 015 0 S 8 07008 77 78 O1 Cab 77 78 GI Van 14033160 A R 12 30 VALVE 030 0 5 8 07008 77 78 CK1 2 5uh Blazer Jimmy 336733 A R N L VALVE std 8 07008 77 78 CK1 2 5uh Blazer Jimmy 336742 A R 34 25 VALVE 003 0 5 8 07008 77 78 CK1 2 Sub Blazer Jimmy 336743 A H 34 25 VALVE 015 0 5 8 07008 ka 0 303 SPRING Valve 77 78 All Blazer Jimmy 3911068 8 2 65 SPRING w damper inlet valve 8 0820A WAREHOUSING AND DISTRIBUTIONDIVISION OF GENERAL MOTORS CORPORATION LT TRUCK 51 REV 2 B3 021 0 201 0 303