COVID-19 UPDATE: We are open for business!

Walk-ins are not allowed but orders may be placed online and picked up at our warehouse.

We are shipping orders as fast as we can with a limited staff. 
Some shipments will be delayed 
regardless of status shown on the website.  
Mercury factory backorders are common right now and we have no guarantee of release dates. 

 UPS has suspended service guarantees and delays are common and beyond our control. 
We are sorry to say there are no refunds for late shipments at this time.

LUCKILY we have been stocking parts for over 40 years and have an enormous selection of parts that ship the same day! 

Please email us with any questions!

Thank you for your patience and stay healthy!

 

Mercury-Mercruiser 12-42307 WASHER

12-42307 WASHER
This is a genuine Mercury Marine factory OEM part, not aftermarket
Please check our current stock level and order below or use the Contact Us form at the bottom of the page for any questions
Manufacturer: Mercury Marine
Availability: 22 available
Manufacturer part number: 42307
Pickup or normally ships: Available - Next business day
$15.40
$15.02
Where Used
5.0, 350, 377 MAG MPI STERNDRIVE - 377 MAG MPI BRAVO5.0, 350, 377 MAG MPI STERNDRIVE - 350 MAG MPI ALPHA/BRAVO
5.0L, 350, 377 MAG MPI STERNDRIVE EC - 5.0L MPI ALPHA/BRAVO EC8.2 MAG HO EC - 8.2L Mag EC (H.O. Model)
525 HP ENGINE - 525 SC (GEN. V) GM 454 V-8 1996BRAVO X (I-II-III) - BRAVO X THREE
MPI STERNDRIVE - 5.0L MPI ALPHA/BRAVO898/200/228/230/260 HP R/MR/ALPHA ONE - 200 (2 BBL.) GM 305 V-81 1985-1986
575 SCI - 575 SCiCUMMINS/MERCRUSER DIESEL (2.8L/165) (4.2L/250) - CMD 4.2 ES 250
8.2L MAG / 8.2L MAG HO - 8.2L Mag (Base Model)5.0L, 350, 377 MAG MPI STERNDRIVE - 377 MAG MPI BRAVO
HP 500 BULLDOG (540 CID) - 500 Bulldog GM 540 V-8 1990-1996898 (STERN DRIVE) 198 (INBOARD) ENGINE - 198 MIE (2 BBL.) GM 305 V-8 1977
500 HP 8.2L (502 CI) ENGINE - 500 (GEN. V) GM 502 V-8 1994-19955.0L, 350, 377 MAG MPI STERNDRIVE EC - 350 MAG MPI HORIZON ALPHA/BRAVO EC
ACCESSORIES MERCRUISER VOLUME I - Exhaust / Cooling Systems and Extension Kits8.2 MAG HO EC - 8.2L Mag EC (Base Model)
540 HP - 540MPI STERNDRIVE - 350 MAG MPI HORIZON ALPHA/BRAVO
5.0, 350, 377 MAG MPI STERNDRIVE EC - 5.0L MPI ALPHA/BRAVO EC5.0L, 350, 377 MAG MPI STERNDRIVE EC - 350 MAG MPI ALPHA/BRAVO EC
8.2 MAG / 8.2 MAG HO EC - 8.2L Mag EC (Base Model)CUMMINS/MERCRUISER 4.2 UNIFICATION - CMD 4.2 ES 320
CUMMINS/MERCRUISER 4.2 UNIFICATION - CMD 4.2 EI 300496 MAG STERNDRIVE - 496 MAG (Base Model)
600 SCI - 600 SCi525 SC - GEN VI - 525 SC - Gen VI
4.3L MPI ALPHA/BRAVO - 4.3L MPI ALPHA/BRAVOCUMMINS/MERCRUISER 4.2 UNIFICATION - CMD 4.2 MI 230
120 HP/2.5L140 HP/3.0L R/MR/ALPHA ONE - 3.0L GM 181 I/L4 1987-19894.3L MPI ALPHA/BRAVO( 262 C.I.D. MULTI PORT INJECTION ) - 4.3L MPI ALPHA/BRAVO
CUMMINS/MERCRUISER DIESEL QSD-4.2L - CMD QSD 4.2 EI 320200/5.0L/LX 260/5.7L 350 MAG ALPHA/BRAVO - 200 (2 BBL.) GM 305 V-8 1987
496 MAG STERNDRIVE - 496 MAG (H.O. Model)5.0L, 350, 377 MAG MPI STERNDRIVE - 350 MAG MPI ALPHA/BRAVO
CUMMINS/MERCRUISER 4.2 UNIFICATION - CMD 4.2 MS 200565 EFI - 565 EFI
5.0L,350 MAG,MX 6.2L MPI STERNDRIVE - MX 6.2L MPI HORIZON BRAVO5.0, 350, 377 MAG MPI STERNDRIVE EC - 350 MAG MPI HORIZON ALPHA/BRAVO EC
D1.7L DTI STERNDRIVE (ALPHA) - D1.7L DTI200/5.0L/LX 260/5.7L 350 MAG ALPHA/BRAVO - 5.0LX (4 BBL.) GM 305 V-8 1988-1995
898/200/228/230/260 HP R/MR/ALPHA ONE - 898 (2 BBL.) GM 305 V-8 1983-19845.0L / 5.7L STERNDRIVE - 5.7L CARB ALPHA/BRAVO
525 HP ENGINE - 525 SC (GEN. V) GM 454 V-8 1992-1995ACCESSORIES MERCRUISER VOLUME I - Fuel/Oil Tanks, Lines, Filter Kits and Corrosion
5.7L/LX 350 MAG ALPHA/BRAVO - 350 MAG. ALPHA (4 BBL.) GM 350 V-8 1996CUMMINS/MERCRUISER DIESEL 4.2L 200/230 - CMD 4.2 MS 200
520 HP - 520CUMMINS/MERCRUISER DIESEL QSD-2.8L - CMD QSD 2.8 EI 170
CUMMINS/MERCRUISER DIESEL QSD-4.2L - CMD QSD 4.2 ES 270CUMMINS/MERCRUISER 4.2 UNIFICATION - CMD 4.2 ES 270
5.0L, 350, 377 MAG MPI STERNDRIVE EC - 377 MAG MPI BRAVO EC350 MPI ALPHA REMAN - 350 MPI ALPHA
500 BULLDOG - 500 Bulldog 1999-2001200/5.0L/LX 260/5.7L 350 MAG ALPHA/BRAVO - 350 MAG. ALPHA GM 350 V-8 1987-1995
260 ENGINE (G.M.) - 260 (4 BBL.) GM 350 V-8 1978-19824.3L MPI ALPHA/BRAVO EC - 4.3L MPI ALPHA/BRAVO EC
500 BULLDOG - 500 BulldogCUMMINS/MERCRUSER DIESEL (2.8L/165) (4.2L/250) - CMD 2.8 ES 165
228 ENGINE (G.M.) - 228 (4 BBL.) GM 305 V-8 1979-1982500 EFI - 500 EFI
450 HP (454 CID) 7.4L ENGINE - 450 (GEN. V) GM 454 V-8 1995-1996MPI STERNDRIVE - MX 6.2L MPI HORIZON BRAVO
HP 500 (502 CID) - 500 (GEN. V) GM 502 V-8 1996CUMMINS/MERCRUSER DIESEL 1.7L-120 - CMD 1.7 MI 120 I/L4
BRAVO X (I-II-III) - BRAVO X ONE120 HP/2.5L140 HP/3.0L R/MR/ALPHA ONE - 140 GM 181 I/L4 1982-1986
EXHAUST/COOLING SYSTEMS AND EXTENSION KITS - Exhaust / Cooling Systems and Extension KitsCUMMINS/MERCRUISER 4.2 UNIFICATION - CMD 4.2 EI 250
898/200/228/230/260 HP R/MR/ALPHA ONE - 260 (4 BBL.) GM 305 V-8 1982-1986228 ENGINE (G.M.) - 228 MIE (4 BBL.) GM 305 V-8 1979-1980
ACCESSORIES MERCRUISER VOLUME I - Power Steering/Tiller Handles/ Shift KitsCUMMINS/MERCRUISER DIESEL QSD-4.2L - CMD QSD 4.2 ES 350
5.0L, 350, 377 MAG MPI STERNDRIVE - 5.0L MPI ALPHA/BRAVO8.2L MAG / 8.2L MAG HO - 8.2L Mag (H.O. Model)
120 HP/2.5L140 HP/3.0L R/MR/ALPHA ONE - 2.5L GM 153 I/L4 1987-19895.0L,350 MAG,MX 6.2L MPI STERNDRIVE - 5.0L MPI ALPHA/BRAVO
496 MAG STERNDRIVE EC - 496 MAG EC (H.O. Model)CUMMINS/MERCRUISER DIESEL QSD-2.8L - CMD QSD 2.8 ES 220
500 CARB (502CID) 8.2L ENGINE (GEN VI) - 500 (GEN. VI)GM 502 V-8 1997-19984.3L CARB ALPHA/BRAVO - 4.3L CARB ALPHA/BRAVO
BRAVO X (I-II-III) - BRAVO X TWOCUMMINS/MERCRUISER DIESEL 4.2L 200/230 - CMD 4.2 MI 230
525 EFI - 525 EFI5.0L,350 MAG,MX 6.2L MPI STERNDRIVE - 350 MAG MPI HORIZON ALPHA/BRAVO
465 HP ENGINE - 465 (GEN. V) GM 502 V-8 1992-1994500 CARB (502CID) 8.2L ENGINE (GEN +) - 500 (GEN. +) GM 502 V-8 1999
5.7L/LX 350 MAG ALPHA/BRAVO - 5.7LX (4 BBL) GM 350 V-8 1996CUMMINS/MERCRUISER DIESEL QSD-2.8L - CMD QSD 2.8 ES 230
8.2 MAG / 8.2 MAG HO EC - 8.2L Mag EC (H.O. Model)5.0, 350, 377 MAG MPI STERNDRIVE - 5.0L MPI ALPHA/BRAVO
200/5.0L/LX 260/5.7L 350 MAG ALPHA/BRAVO - 260 GM 350 V-8 1987200/5.0L/LX 260/5.7L 350 MAG ALPHA/BRAVO - 5.7L GM 350 V-8 1988-1995
CUMMINS/MERCRUISER DIESEL QSD-2.8L - CMD QSD 2.8 ES 2105.0, 350, 377 MAG MPI STERNDRIVE EC - 377 MAG MPI BRAVO EC
496 MAG STERNDRIVE EC - 496 MAG EC (Base Model)120 HP/2.5L140 HP/3.0L R/MR/ALPHA ONE - 120 GM 153 I/L4 1983-1986
Customers who bought this item also bought

Mercury-Mercruiser 10-57053 SCREW (.500-20 x 4.500)

10-57053 SCREW (.500-20 x 4.500)
This is a genuine Mercury Marine factory OEM part, not aftermarket
Please check our current stock level and order below or use the Contact Us form at the bottom of the page for any questions
$4.30 $4.20

Mercury-Mercruiser 11-898832 NUT (.500-20)

11-898832 NUT (.500-20)
This is a genuine Mercury Marine factory OEM part, not aftermarket
Please check our current stock level and order below or use the Contact Us form at the bottom of the page for any questions
$2.80 $2.74

Mercury-Mercruiser 12-35777 WASHER (.5156 x 1.375 x .

12-35777 WASHER (.5156 x 1.375 x .
This is a genuine Mercury Marine factory OEM part, not aftermarket
Please check our current stock level and order below or use the Contact Us form at the bottom of the page for any questions
$1.90 $1.86

Mercury-Mercruiser 13-41471 LOCKWASHER (.375)

13-41471 LOCKWASHER (.375)
This is a genuine Mercury Marine factory OEM part, not aftermarket
Please check our current stock level and order below or use the Contact Us form at the bottom of the page for any questions
$1.70 $1.66

Mercury-Mercruiser 25-25439 O-RING (.862 x .103)

25-25439 O-RING (.862 x .103)
This is a genuine Mercury Marine factory OEM part, not aftermarket
Please check our current stock level and order below or use the Contact Us form at the bottom of the page for any questions
$1.60 $1.57

Mercury-Mercruiser 16-56296 STUD (.437-20 x 4.750)

16-56296 STUD (.437-20 x 4.750)
This is a genuine Mercury Marine factory OEM part, not aftermarket
Please check our current stock level and order below or use the Contact Us form at the bottom of the page for any questions
$11.50 $11.22