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Mercury Mercruiser Marine - VALVE ASSY-CHECK (#21-42657A3)

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$5.60

Part #: 21-42657A3

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VALVE ASSY-CHECK
VALVE ASSY-CHECK

Mercury Assemblies

Reed Block and Cylinder Head
MARINERV-135
MARINERV-150
MERCURY/MARINER 135/150 H.P (V-6) Reed Block and Cylinder Head
CYLINDER BLOCK/CRANKSHAFT/PISTON
MERCURY4/5 (1 CYL. PRODUCT OF JAPAN)
MERCURY 4/5 HP CYLINDER BLOCK/CRANKSHAFT/PISTON
REED BLOCK AND CYLINDER HEAD
MARINERMAGNUM II
MERCURYXR-4
MERCURY/MARINER XR-4 MAGNUM II REED BLOCK AND CYLINDER HEAD
Cylinder Block And Crankcase
MARINER100 (4 CYL.)
MARINER115 (4 CYL.)
MERCURY/MARINER 100 / 115 HP (4 CYLINDER) Cylinder Block And Crankcase
Cylinder Block and Crankcase
MERCURY/MARINER 70/75/80/90 HP (3 CYLINDER)) Cylinder Block and Crankcase
CYLINDER BLOCK AND COVERS
MARINER15
MARINER6
MERCURY8
MARINER9.9
MERCURY/MARINER 6/8/9.9/15 HP CYLINDER BLOCK AND COVERS
Reed Block and Cylinder Head
MERCURY/MARINER 135 HP/ 150 HP (V-6) Reed Block and Cylinder Head
Reed Block and Cylinder Head
MERCURY/MARINER XR-4/MAGNUM II Reed Block and Cylinder Head
REED BLOCK AND CYLINDER HEAD
MARINERV-175
MERCURY/MARINER 175 H.P. (V-6) REED BLOCK AND CYLINDER HEAD
CYLINDER BLOCK AND END CAPS
MERCURY250/275
MERCURY/MARINER 250/275 HP CYLINDER BLOCK AND END CAPS
Cylinder Block And Crankcase
MERCURY/MARINER 75/90 HP (3 CYLINDER) Cylinder Block And Crankcase
FUEL PUMPS
MERCURY300 (3.4 LITRE)
MERCURY 3.4 LITRE FUEL PUMPS
Cylinder Block and Covers
MERCURY/MARINER XR-10/MAGNUM 10/SEA PRO 10/MARATHON 10 Cylinder Block and Covers
CYLINDER BLOCK
FORCE70 H.P. (1991-1995)
FORCE 70 H.P. CYLINDER BLOCK
RECIRCULATION SYSTEM (90A,92C)
FORCE120 H.P. (1990-1994)
FORCE 120 H.P. RECIRCULATION SYSTEM (90A,92C)
CYLINDER BLOCKS AND END CAPS
RACE OUTBOARDMERC MOD-VP
RACE OUTBOARD MOD-VP CYLINDER BLOCKS AND END CAPS
CYLINDER BLOCK AND END CAPS
RACE OUTBOARDMERC/MAR 2.4L (EFI)
RACE OUTBOARD 2.4L (EFI) BASS/OFFSHORE CYLINDER BLOCK AND END CAPS
CYLINDER BLOCK AND END CAPS
RACE OUTBOARD 2.4L EFI BASS/OFFSHORE CYLINDER BLOCK AND END CAPS
CYLINDER BLOCK AND END CAPS
RACE OUTBOARDMERC FORMULA I (2L EFI)
RACE OUTBOARD FORMULA 1 2 LITRE (EFI) CYLINDER BLOCK AND END CAPS
CYLINDER BLOCK AND END CAPS
RACE OUTBOARDMERC FORMULA I (CARB)
RACE OUTBOARD FORMULA 1 (CARBURETOR) CYLINDER BLOCK AND END CAPS
CYLINDER BLOCK AND COVERS
RACE OUTBOARD 10 XS CYLINDER BLOCK AND COVERS
CYLINDER BLOCK AND END CAPS
RACE OUTBOARD 2.4L EFI / 2.4L EFI OFFSHORE CYLINDER BLOCK AND END CAPS
CYLINDER BLOCK AND END CAPS
RACE OUTBOARD 2.4L EFI / 2.4L EFI OFFSHORE CYLINDER BLOCK AND END CAPS
REED BLOCK AND CYLINDER HEAD
RACE OUTBOARDMERC XR2
RACE OUTBOARD XR-2 REED BLOCK AND CYLINDER HEAD
CYLINDER BLOCK AND END CAPS
RACE OUTBOARDMERC MOD-VP (EFI)
RACE OUTBOARD MOD - VP (EFI) CYLINDER BLOCK AND END CAPS
CYLINDER BLOCK AND END CAPS
RACE OUTBOARDMERC/MAR 2.5L (EFI)
RACE OUTBOARD 2.5L EFI 2.5L EFI OFFSHORE CYLINDER BLOCK AND END CAPS
CYLINDER BLOCK AND END CAPS
RACE OUTBOARDMERC/MAR 2.5L (EFI)/(EFI-OFFSHORE)
RACE OUTBOARD 2.5L (EFI) 2.5L (EFI-OFFSHORE) CYLINDER BLOCK AND END CAPS
CYLINDER BLOCK ASSEMBLY (SERIAL # 0E138600 THRU 0E181482)
FORCE75 H.P. (1996)
FORCE75 H.P. (1997)
FORCE FORCE 75 H.P. CYLINDER BLOCK ASSEMBLY (SERIAL # 0E138600 THRU 0E181482)
CYLINDER BLOCK ASSEMBLY (SERIAL # 0E181483 THRU 0E287999)
FORCE FORCE 75 H.P. CYLINDER BLOCK ASSEMBLY (SERIAL # 0E181483 THRU 0E287999)
CYLINDER BLOCK AND END CAPS
RACE OUTBOARD 2.5L EFI 2.5L EFI OFFSHORE CYLINDER BLOCK AND END CAPS
Fuel Pump(Design II)
MERCURYV-200
MERCURY/MARINER 200 H.P. (V-6) (1978-1988 COMBINED BOOKS) Fuel Pump(Design II)
Exhaust Manifold and Exhaust Plate
MARINERV-150 Magnum
MARINERV-150 Marathon
MERCURYV-150 Work
MERCURYV-150-XR-2
MERCURYV-1500
MERCURY/MARINER 150 H.P. XR-2 MARATHON MAGNUM (V-6) (1978-1985 COMBINED BOOK) Exhaust Manifold and Exhaust Plate
CYLINDER BLOCK AND CRANKCASE
MERCURY45 JET
MERCURY50 (3 CYL.)
MERCURY55 (3 CYL.)
MERCURY60 (3 CYL.)
MERCURY/MARINER 50/55/60 HP JET 45 CYLINDER BLOCK AND CRANKCASE
RECIRCULATION SYSTEM
FORCE150 H.P. (1989-1992)
FORCE150 H.P. (1992-1994)
FORCE 150 H.P. RECIRCULATION SYSTEM
RECIRCULATION SYSTEM
FORCE150 H.P. (1989-1992)
FORCE150 H.P. (1992-1994)
FORCE 150 H.P. RECIRCULATION SYSTEM
CYLINDER BLOCK AND CRANKCASE
MERCURY70 (3 CYL.)
MARINER75 (3 CYL.)
MARINER80 (3 CYL.)
MARINER90 (3 CYL.)
MERCURY/MARINER 70/75/80/90 HP (3 CYLINDER) CYLINDER BLOCK AND CRANKCASE
Divider Plate and Exhaust Plate
MERCURY/MARINER 175 H.P. V-6 (1976-1988 COMBINED BOOKS) Divider Plate and Exhaust Plate
Cylinder Block and Crankcase
MERCURY/MARINER 100/115/125 HP 80 JET  (4 CYLINDER) Cylinder Block and Crankcase
CYLINDER BLOCK
MARINER30 (2 CYL.)
MARINER40 (2 CYL.)
MERCURY/MARINER 30/40 H.P. CYLINDER BLOCK
Cylinder Block and Covers
MERCURY/MARINER 6/8/SAILMATE 9.9/SAILPOWER 15 H.P. Cylinder Block and Covers
CYLINDER BLOCK/CRANKSHAFT/PISTON
MARINER4/5
MERCURY/MARINER 4/5 HP CYLINDER BLOCK/CRANKSHAFT/PISTON
CYLINDER BLOCK (USA-0G127499/BEL-9836632 & BELOW)
MERCURY65 JET
MERCURY/MARINER 75/90 HP 65 JET (3 CYLINDER) CYLINDER BLOCK (USA-0G127499/BEL-9836632 & BELOW)
CYLINDER BLOCK (USA-S/N-0G127500/BEL-9836633 & UP)
MERCURY/MARINER 75/90 HP 65 JET (3 CYLINDER) CYLINDER BLOCK (USA-S/N-0G127500/BEL-9836633 & UP)
Cylinder Block and Covers
MARINER10 MAGNUM
MARINER10 MARATHON
MERCURY10 SEA PRO
MARINER15 MARATHON
MERCURY15 SEA PRO
MERCURYXR10
MERCURY/MARINER XR/MAGNUM 10/SEAPRO/MARATHON 10/SEAPRO/MARATHON 15 Cylinder Block and Covers
Cylinder Block
MERCURY/MARINER 30/40 (2 CYLINDER) 2-STROKE Cylinder Block
CYLINDER BLOCK AND END CAP
MERCURY225 (3.0L EFI)
MERCURY250 (3.0L EFI)
MERCURY/MARINER 225/250 EFI (3.0L) CYLINDER BLOCK AND END CAP
Cylinder Block
MERCURY65 JET (3 CYL.)
MERCURY/MARINER 75/90 HP 65 JET (3 CYLINDER) Cylinder Block
CYLINDER BLOCK AND CRANKCASE
MERCURY/MARINER 50/55/60 JET 45 CYLINDER BLOCK AND CRANKCASE
CYLINDER BLOCK AND END CAP
MERCURY225 (3.0L CARB)
MARINER225 MARATHON (3.0L CARB)
MERCURY225 SEAPRO (3.0L CARB)
MERCURY/MARINER 225 AND 225 SEAPRO/MARATHON (3.0L CARB) CYLINDER BLOCK AND END CAP
CYLINDER BLOCK AND END CAP
MERCURY200 (DFI)
MERCURY/MARINER 200 DFI 3.0L CYLINDER BLOCK AND END CAP
CYLINDER BLOCK ASSEMBLY
FORCE75 H.P. (1998)
FORCE FORCE 75 H.P. (1998) CYLINDER BLOCK ASSEMBLY
Cylinder Block and End Caps
RACE OUTBOARD 2.5L (EFI) 2.5L (EFI-OFFSHORE) Cylinder Block and End Caps
BLEED SYSTEM
RACE OUTBOARDS3000
RACE OUTBOARD HI PERF MERC/MAR S3000 BLEED SYSTEM
BLEED SYSTEM
RACE OUTBOARDFORMULA I (2 LITRE EFI)
RACE OUTBOARD FORMULA 1 2 LITRE - EFI BLEED SYSTEM
CYLINDER BLOCK AND END CAPS
RACE OUTBOARD FORMULA 1 2 LITRE - EFI CYLINDER BLOCK AND END CAPS
Cylinder Block/Crankshaft/Piston
MERCURY4 (2-STROKE)
MERCURY5 (2-STROKE)
MERCURY/MARINER 4/5HP 2-STROKE Cylinder Block/Crankshaft/Piston
CYLINDER BLOCK AND CRANKCASE
MARINER125 (4 CYL.)
MARINER80 JET
MERCURY/MARINER 100/115/125 HP 80 JET  (4 CYLINDER) CYLINDER BLOCK AND CRANKCASE
Cylinder Block
MERCURY40 (International)
MERCURY40 LIGHTNING XR (International)
MERCURY50MH
MERCURY/MARINER 40/40 LIGHTNING XR/50 Cylinder Block
Cylinder Block
MERCURY/MARINER 75/90 HP 65 JET (3 CYLINDER) Cylinder Block
Cylinder Block and Crankcase
MERCURY/MARINER 115/125 HP 80 JET  (4 CYLINDER) Cylinder Block and Crankcase
Cylinder Block
MERCURY/MARINER 30/40 (2 CYLINDER) 2-STROKE Cylinder Block
Carburetor
MARINER6 (2 CYL.)(2-STROKE)(International)
MERCURY8 (2 CYL.)(2-STROKE)(International)
MERCURY/MARINER 6/8 HP INTERNATIONAL Carburetor
Cylinder Block
MARINER15 (2 CYL.) (International)
MERCURY18 (2 CYL.) (International)
MERCURY9.9 (2 CYL.) (International)
MERCURY/MARINER 9.9/15/18 HP (2 CYLINDER)(INTERNATIONAL) Cylinder Block
Cylinder Block, SN 0N162743 and below
MARINER25 (2 CYL.)(2-STROKE)(International)
MERCURY25 Jet (2 CYL.)(2-STROKE)(International)
MARINER30 (2 CYL.)(2-STROKE)(International)
MERCURY/MARINER 25/25 JET/30HP (2 CYL/430CC) INTERNATIONAL Cylinder Block, SN 0N162743 and below
Cylinder Block, SN 0N162744 and up
MERCURY/MARINER 25/25 JET/30HP (2 CYL/430CC) INTERNATIONAL Cylinder Block, SN 0N162744 and up
Carburetor
MARINER6 (2 Cyl.)(International)
MARINER8 (2 Cyl.)(International)
MERCURY8 SEAPRO (2 CYL.)(International)
MERCURY9.8 SEAPRO (2 Cyl.)(International)
MERCURY/MARINER 6/8/9.8 2-STROKE (INTERNATIONAL) Carburetor
CYLINDER BLOCK AND END CAPS
RACE OUTBOARD HI PERF MERC/MAR S3000 CYLINDER BLOCK AND END CAPS
Cylinder Block and End Caps
RACE OUTBOARD2.5L (EFI)/(EFI-OFFSHORE)
RACE OUTBOARD 2.5L/2.5L OFFSHORE EFI Cylinder Block and End Caps
CYLINDER BLOCK AND CRANKCASE ASSEMBLY
MERCURY800 (4 CYL.), 80 (4 CYL.)
MERCURY MERC 800E CYLINDER BLOCK AND CRANKCASE ASSEMBLY
CYLINDER BLOCK AND CRANKCASE ASSEMBLY
MERCURY400 (2 CYL.)
MERCURY MERC 400 CYLINDER BLOCK AND CRANKCASE ASSEMBLY
CYLINDER BLOCK AND CRANKCASE ASSEMBLY
MERCURY650 (4 CYL.)
MERCURY MERC 650 CYLINDER BLOCK AND CRANKCASE ASSEMBLY
CYLINDER BLOCK AND CRANKCASE ASSEMBLY
MERCURY1150
MERCURY MERC 1150E-SS CYLINDER BLOCK AND CRANKCASE ASSEMBLY
CYLINDER BLOCK AND CRANKCASE ASSEMBLY
MERCURY1350
MERCURY MERC 1350 CYLINDER BLOCK AND CRANKCASE ASSEMBLY
CYLINDER BLOCK AND CRANKCASE ASSEMBLY
MERCURY1400
MERCURY MERC 1400EL-SS CYLINDER BLOCK AND CRANKCASE ASSEMBLY
END CAPS, MANIFOLD AND EXHAUST COVERS
MERCURY500
MERCURY MERC 500 END CAPS, MANIFOLD AND EXHAUST COVERS
CYLINDER BLOCK AND CRANKCASE ASSEMBLY
MERCURY650 (3 CYL.)
MERCURY MERC 650E CYLINDER BLOCK AND CRANKCASE ASSEMBLY
CYLINDER BLOCK AND CRANKCASE ASSEMBLY
MERCURY650 (3 CYL.)
MERCURY MERC 650E CYLINDER BLOCK AND CRANKCASE ASSEMBLY
CYLINDER BLOCK AND CRANKCASE ASSEMBLY
MERCURY200
MERCURY MERC 200 CYLINDER BLOCK AND CRANKCASE ASSEMBLY
CYLINDER BLOCK AND CRANKCASE ASSEMBLY
MERCURY40 (1 CYL.)
MERCURY MERC 40 CYLINDER BLOCK AND CRANKCASE ASSEMBLY
CYLINDER BLOCK AND CRANKCASE ASSEMBLY
MERCURY75
MERCURY MERC 75 CYLINDER BLOCK AND CRANKCASE ASSEMBLY
CYLINDER BLOCK AND CRANKCASE ASSEMBLY
MERCURY110
MERCURY MERC 110 CYLINDER BLOCK AND CRANKCASE ASSEMBLY
CYLINDER BLOCK AND COIL MOUNTING BRACKET (SERIAL GROUP #5)
MERCURY402
MERCURY MERC 402 CYLINDER BLOCK AND COIL MOUNTING BRACKET (SERIAL GROUP #5)
CYLINDER BLOCK AND CRANKCASE ASSEMBLY
MERCURY850 (4 CYL.)
MERCURY MERC 850 (4 CYLINDER) CYLINDER BLOCK AND CRANKCASE ASSEMBLY
CYLINDER BLOCK AND CRANKCASE ASSEMBLY
MERCURY850 (4 CYL.)
MERCURY MERC 850 (4 CYLINDER) CYLINDER BLOCK AND CRANKCASE ASSEMBLY
END CAPS, MANIFOLD AND EXHAUST COVERS
MERCURY MERC 850 (4 CYLINDER) END CAPS, MANIFOLD AND EXHAUST COVERS
CYLINDER BLOCK AND CRANKCASE ASSEMBLY
MERCURY1500
MERCURY MERC 1500 CYLINDER BLOCK AND CRANKCASE ASSEMBLY
CYLINDER BLOCK AND CRANKCASE ASSEMBLY
MERCURY1500
MERCURY MERC 1500 CYLINDER BLOCK AND CRANKCASE ASSEMBLY
END CAPS, MANIFOLD AND EXHAUST COVERS (CONT)
MERCURY MERC 1500 END CAPS, MANIFOLD AND EXHAUST COVERS (CONT)
CYLINDER BLOCK AND CRANKCASE ASSEMBLY
MERCURY MERC 1150 CYLINDER BLOCK AND CRANKCASE ASSEMBLY
CYLINDER BLOCK AND CRANKCASE ASSEMBLY
MERCURY MERC 1150 CYLINDER BLOCK AND CRANKCASE ASSEMBLY
END CAP, MANIFOLD AND EXHAUST COVERS
MERCURY MERC 1150 END CAP, MANIFOLD AND EXHAUST COVERS
CYLINDER BLOCK AND CRANKCASE ASSEMBLY
MERCURY MERC 200 CYLINDER BLOCK AND CRANKCASE ASSEMBLY
CYLINDER BLOCK AND CRANKCASE ASSEMBLY
MERCURY MERC 850 CYLINDER BLOCK AND CRANKCASE ASSEMBLY
FUEL PUMP AND CARBURETOR
MERCURYV-225
MERCURY MERC V-225 FUEL PUMP AND CARBURETOR
CYLINDER BLOCK AND CRANKCASE ASSEMBLY
MARINER85
MARINER MARINER 85 CYLINDER BLOCK AND CRANKCASE ASSEMBLY
REED PLATE AND RECIRCULATION SYSTEM
FORCE120 H.P. (1990 L-DRIVE)
FORCE FORCE 1990 120 H.P. "C" MODELS L-DRIVE REED PLATE AND RECIRCULATION SYSTEM
REED PLATE AND RECIRCULATION SYSTEM
FORCE120 H.P. (1991 L-DRIVE)
FORCE FORCE 1991 120 H.P "B" MODEL L-DRIVE REED PLATE AND RECIRCULATION SYSTEM
REED PLATE AND RECIRCULATION SYSTEM
FORCE FORCE 1991 120 H.P "D" MODEL L-DRIVE REED PLATE AND RECIRCULATION SYSTEM
REED PLATE AND RECIRCULATION SYSTEM
FORCE120 H.P. (1992 L-DRIVE)
FORCE FORCE 120 H.P. "L" - DRIVE "B" MODELS REED PLATE AND RECIRCULATION SYSTEM