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Parts for MerCruiser Race Engine and Drive 525 EFI Engine Components (Cylinder Head)

Engine Diagram

Ref. No. Part No. Description Manufacturer List Price Your Price Order
#1 845708A 7 COVER ASSEMBLY, Rocker Valve - Blue, Port (1 required per assembly)
COVER ASSY-PORT   O - Replaced by -8M0050913  
845708A 7This part has been superseded. COVER ASSY-PORT O - Replaced by -8M0050913
(more info)
    UnavailableUnavailable Parts
COVER ASSEMBLY Ro 8M0050913  
8M0050913OEM Part 8M0050913 - Cover Assembly - Port (more info) About Mercury Marine $378.28 $378.28 Add to shopping cart
Available to order:
Usually ships
within 8 days
#2 845708A 9 COVER ASSEMBLY, Rocker Valve - Blue, Starboard (1 required per assembly)
COVER ASSY-STBD   O - Replaced by -8M0052328  
845708A 9This part has been superseded. COVER ASSY-STBD O - Replaced by -8M0052328
(more info)
    UnavailableUnavailable Parts
COVER ASSY-STBD 8M0052328  
8M0052328OEM Part 8M0052328 - Cover Assembly - Stbd (more info) About Mercury Marine $371.20 $371.20 Add to shopping cart
Available to order:
Usually ships
within 8 days
#3 27-811588 GASKET, Rocker Cover (2 required per assembly)
278M0092920 27-811588 27-811588
27-811588OEM Part 27-811588 - Gasket (more info) About Mercury Marine $141.67 $40.80 Add to shopping cart
9 in stock. Explain stock levels
ROCKER COVER GASKET  
27-8M0092920OEM Part 27-8M0092920 - ROCKER Cover Gasket (more info) About Mercury Marine $83.25 $83.25 Add to shopping cart
10+ in stock. Explain stock levels
ROCKER COVER GASKET 18-25002
18-25002OEM Match 18-25002 - Gasket 27-811588 (more info) About Sierra Marine $131.99 $107.39 Add to shopping cart
Available to order:
Usually ships
within 8 days
#4 10-39349 SCREW, (.312-18 x .750) Stainless Steel (2 required per assembly)
SCREW (.312-18 x 10-39349 10-39349
10-39349OEM Part 10-39349 - Screw - Priced Individually (more info) About Mercury Marine $1.40 $1.40 Add to shopping cart
6 in stock. Explain stock levels
#5 12-70132 WASHER, (.323 x .563 x .063) Stainless Steel (2 required per assembly)
WASHER @5         O - Replaced by 12-8M0042642  
12-70132This part has been superseded. WASHER @5 O - Replaced by 12-8M0042642
(more info)
    UnavailableUnavailable Parts
WASHER (.323 x .5 12-8M0042642 12-8M0042642
12-8M0042642OEM Part 12-8M0042642 - Washer - Priced Individually (more info) About Mercury Marine $1.40 $1.40 Add to shopping cart
7 in stock. Explain stock levels
#6 25-26802 O-RING, (.424 x .103) (2 required per assembly)
O-RING (.424 x .1 25-26802 25-26802
25-26802OEM Part 25-26802 - O-Ring - Priced Individually (more info) About Mercury Marine $2.80 $2.80 Add to shopping cart
1 in stock. Explain stock levels
O-Ring 18-7180-9
18-7180-9OEM Match 18-7180-9 - O-Ring (PK5 ) 925055 (more info)
Replaces OEM #0303347
About Sierra Marine $14.95 $10.08 Add to shopping cart
1 in stock. Explain stock levels
#7 25-811553 GROMMET (2 required per assembly)
GROMMET 25-811553  
25-811553OEM Part 25-811553 - Grommet (more info) About Mercury Marine $25.42 $25.42 Add to shopping cart
Available to order:
Usually ships
within 8 days
#8 97850 ELBOW, 90 Degree, Breather (2 required per assembly)
ELBOW-BREATHER    O - Replaced by -97850T  
97850This part has been superseded. ELBOW-BREATHER O - Replaced by -97850T
(more info)
    UnavailableUnavailable Parts
ELBOW 90 Degree 97850T 97850T
97850TOEM Part 97850T - Elbow (more info) About Mercury Marine $3.80 $3.80 Add to shopping cart
Available to order:
Usually ships
within 8 days
#9 37-849950 DECAL, Oil Fill Cap (2 required per assembly)
DECAL Oil Fill Ca 37-849950  
37-849950OEM Part 37-849950 - Decal (more info) About Mercury Marine $4.13 $4.13 Add to shopping cart
Available to order:
Usually ships
within 8 days
#10 36-845753T 1 CAP, Oil Filler (2 required per assembly)
CAP 845753T 1 845753T 1
845753T 1OEM Part 845753T 1 - Oil Fill Cap (more info) About Mercury Marine $13.00 $13.00 Add to shopping cart
Available to order:
Usually ships
within 8 days
#11 54-42553 J CLIP (1 required per assembly)
J CLIP 54-42553  
54-42553OEM Part 54-42553 - J Clip (more info) About Mercury Marine $4.20 $4.20 Add to shopping cart
Available to order:
Usually ships
within 8 days
#12 54-858951 J CLIP (3 required per assembly)
J CLIP 54-858951  
54-858951OEM Part 54-858951 - J Clip (more info) About Mercury Marine $4.60 $4.60 Add to shopping cart
Available to order:
Usually ships
within 8 days
#14 22-849999 FITTING, Tee (1 required per assembly)
FITTING 22-849999  
22-849999OEM Part 22-849999 - Fitting (more info) About Mercury Marine $4.10 $4.10 Add to shopping cart
Available to order:
Usually ships
within 8 days
#15 32-15894 31 TUBING, (20.00 Inches Bulk), Cut As Required - Breather (1 required per assembly)
TUBING (20.00 Inc 32-15894 31 32-15894 31
32-15894 31OEM Part 32-15894 31 - Tube - 20 Inch (more info) About Mercury Marine $27.58 $27.58 Add to shopping cart
Available to order:
Usually ships
within 8 days
#16 56762 TIE STRAP, (4.00 Inches) (AR required per assembly)
TIE STRAP (4.00 I 56762 56762
56762OEM Part 56762 - Tie Strap - Priced Individually (more info) About Mercury Marine $0.30 $0.30 Add to shopping cart
10+ in stock. Explain stock levels
#17 11-35888 NUT, (.250-28) Stainless Steel (14 required per assembly)
NUT (.250-28) Sta 11-35888 11-35888
11-35888OEM Part 11-35888 - Nut - Priced Individually (more info) About Mercury Marine $4.70 $1.14 Add to shopping cart
10+ in stock. Explain stock levels
S.S. Steel Locknut 18-3722-9
18-3722-9OEM Match 18-3722-9 - Lock Nut, 121731, 11-35888 (more info)
Replaces OEM #0121731
About Sierra Marine $14.95 $7.67 Add to shopping cart
Available to order:
Usually ships
within 8 days
#18 12-846673 WASHER, (.265 x .500 x .060) Stainless Steel (14 required per assembly)
WASHER (.265 x .5 12-846673  
12-846673OEM Part 12-846673 - Washer (more info) About Mercury Marine $0.80 $0.80 Add to shopping cart
Available to order:
Usually ships
within 8 days
#19 16-56766 STUD, (.250-20/.250-28 x 1.380) (14 required per assembly)
STUD (.250-20/.25 16-56766 16-56766
16-56766OEM Part 16-56766 - Stud - Priced Individually (more info) About Mercury Marine $2.40 $2.40 Add to shopping cart
Available to order:
Usually ships
within 8 days
#20 843140 LOCK, Valve Stem (32 required per assembly)
LOCK-VALVE @2     O - Replaced by -8M0042989 843140
843140This part has been superseded. LOCK-VALVE @2 O - Replaced by -8M0042989
(more info)
    UnavailableUnavailable Parts
LOCK-VALVE Note: must be ordered in multiples of 2 8M0042989 8M0042989
8M0042989OEM Part 8M0042989 - Lock - Valve - Priced Individually (more info) About Mercury Marine $5.04 $5.04 Add to shopping cart
Available to order:
Usually ships
within 8 days
#21 24-843081A01 SPRING/RETAINER KIT, (16 Per Kit) (1 required per assembly)
SPRING/RETAINER K 24-843081A01  
24-843081A01OEM Part 24-843081A01 - Spr/Ret Kit -16PCS (more info) About Mercury Marine $1,140.44 $1,140.44 Add to shopping cart
Available to order:
Usually ships
within 8 days
#22 NSS NOT SOLD SEPARATE, Retainer (1 required per assembly)
#23 840678 SEAT, Spring (16 required per assembly)
SEAT Spring 840678 840678
840678OEM Part 840678 - Seat - Spring (more info) About Mercury Marine $11.42 $11.42 Add to shopping cart
Available to order:
Usually ships
within 8 days
#24 26-842755 SEAL, Valve, Intake And Exhaust (16 required per assembly)
SEAL Valve 26-842755  
26-842755OEM Part 26-842755 - Seal - Valve (more info) About Mercury Marine $7.80 $7.80 Add to shopping cart
Available to order:
Usually ships
within 8 days
#25 15-845669 SHIM, Valve Spring (.015) (AR required per assembly)
SHIM-.015 @2      O  
15-845669 SHIM-.015 @2 O
(more info)
    UnavailableUnavailable Parts
#25 15-77624 SHIM, Valve Spring (.030) (AR required per assembly)
SHIM Valve Spring 15-77624  
15-77624OEM Part 15-77624 - Shim -.030 (more info) About Mercury Marine $3.50 $3.50 Add to shopping cart
Available to order:
Usually ships
within 8 days
#25 15-77625 SHIM, Valve Spring (.060) (AR required per assembly)
SHIM Valve Spring 15-77625  
15-77625OEM Part 15-77625 - Shim -.060 (more info) About Mercury Marine $2.14 $2.14 Add to shopping cart
Available to order:
Usually ships
within 8 days
#26 843080 VALVE, Exhaust (8 required per assembly)
VALVE Exhaust 843080 843080
843080OEM Part 843080 - Exhaust Valve (more info) About Mercury Marine $116.87 $116.87 Add to shopping cart
Available to order:
Usually ships
within 8 days
#27 821024T VALVE, Intake, Standard - 2.250 Diameter (8 required per assembly)
VALVE Intake 821024T 821024T
821024TOEM Part 821024T - Inlet Valve (more info) About Mercury Marine $80.92 $80.92 Add to shopping cart
Available to order:
Usually ships
within 8 days
#28 848262 PUSH ROD, (7.550) (8 required per assembly) - Inlet
PUSH ROD (7.550) 848262 848262
848262OEM Part 848262 - Push Rod (more info) About Mercury Marine $41.25 $41.25 Add to shopping cart
Available to order:
Usually ships
within 8 days
#28 848264 PUSH ROD, (8.550) (8 required per assembly) - Exhaust
PUSH ROD (8.550) 848264 848264
848264OEM Part 848264 - Push Rod (more info) About Mercury Marine $41.25 $41.25 Add to shopping cart
Available to order:
Usually ships
within 8 days
#29 840942 GUIDE, Pushrod (8 required per assembly)
GUIDE Pushrod 840942 840942
840942OEM Part 840942 - Guide - Push Rod (more info) About Mercury Marine $26.50 $26.50 Add to shopping cart
Available to order:
Usually ships
within 8 days
#30 845618T ROCKER ARM ASSEMBLY (16 required per assembly)
ROCKER ARM ASSEMB 845618T 845618T
845618TOEM Part 845618T - Rocker Arm Assembly (more info) About Mercury Marine $95.19 $95.19 Add to shopping cart
Available to order:
Usually ships
within 8 days
#31 11-848610 NUT, Rocker Arm Valve (16 required per assembly)
NUT               O - Replaced by 11-8M0043537 11-848610
11-848610This part has been superseded. NUT O - Replaced by 11-8M0043537
(more info)
    UnavailableUnavailable Parts
NUT-ROCKER        O  
11-8M0043537 NUT-ROCKER O
(more info)
    UnavailableUnavailable Parts
#32 16-95820 STUD, Rocker Arm Valve, Intake (8 required per assembly)
STUD Rocker Arm V 16-95820 16-95820
16-95820OEM Part 16-95820 - Stud (more info) About Mercury Marine $10.00 $10.00 Add to shopping cart
1 in stock. Explain stock levels
#32 16-843129 STUD, Rocker Arm Valve, Exhaust (8 required per assembly)
STUD Rocker Arm V 16-843129 16-843129
16-843129OEM Part 16-843129 - Stud (more info) About Mercury Marine $13.40 $13.40 Add to shopping cart
Available to order:
Usually ships
within 8 days
#33 10-843918 SCREW, (.438-14 x 4.060) (14 required per assembly)
SCREW             O - Replaced by 10-8M0000482  
10-843918This part has been superseded. SCREW O - Replaced by 10-8M0000482
(more info)
    UnavailableUnavailable Parts
SCREW (.438-14 x 10-8M0000482 10-8M0000482
10-8M0000482OEM Part 10-8M0000482 - Screw (more info) About Mercury Marine $5.90 $5.90 Add to shopping cart
Available to order:
Usually ships
within 8 days
#33 10-843919 SCREW, (.438-14 x 5.120) (10 required per assembly)
SCREW             O - Replaced by 10-8M0000467  
10-843919This part has been superseded. SCREW O - Replaced by 10-8M0000467
(more info)
    UnavailableUnavailable Parts
SCREW (.438-14 x 10-8M0000467 10-8M0000467
10-8M0000467OEM Part 10-8M0000467 - Screw (more info) About Mercury Marine $10.70 $10.70 Add to shopping cart
Available to order:
Usually ships
within 8 days
#34 12-841990 WASHER, Special - Black (32 required per assembly)
WASHER Special - 12-841990  
12-841990OEM Part 12-841990 - Washer (more info) About Mercury Marine $1.30 $1.30 Add to shopping cart
Available to order:
Usually ships
within 8 days
#35 900-843425A04 CYLINDER HEAD ASSEMBLY (1 required per assembly) - Starboard
HEAD ASY-CYL-STBD O - Replaced by 900-843944A04  
843425A04This part has been superseded. HEAD ASY-CYL-STBD O - Replaced by 900-843944A04
(more info)
    UnavailableUnavailable Parts
CYLINDER HEAD ASS 900-843944A04  
900-843944A04OEM Part 900-843944A04 - Cylinder Head Assembly - Stbd (more info) About Mercury Marine $1,943.28 $1,943.28 Add to shopping cart
Available to order:
Usually ships
within 8 days
#35 900-843425A05 CYLINDER HEAD ASSEMBLY (1 required per assembly) - Port
HEAD ASY-CYL-PORT O - Replaced by 900-843944A05  
900-843425A05This part has been superseded. HEAD ASY-CYL-PORT O - Replaced by 900-843944A05
(more info)
    UnavailableUnavailable Parts
CYLINDER HEAD ASS 900-843944A05  
900-843944A05OEM Part 900-843944A05 - Cylinder Head Assembly - Port (more info) About Mercury Marine $1,943.28 $1,943.28 Add to shopping cart
Available to order:
Usually ships
within 8 days
#36 10-843917 SCREW, (.438-14 x 2.060) (8 required per assembly)
SCREW             O - Replaced by 10-8M0000463  
10-843917This part has been superseded. SCREW O - Replaced by 10-8M0000463
(more info)
    UnavailableUnavailable Parts
SCREW (.438-14 x 10-8M0000463 10-8M0000463
10-8M0000463OEM Part 10-8M0000463 - Screw (more info) About Mercury Marine $9.90 $9.90 Add to shopping cart
Available to order:
Usually ships
within 8 days
#37 27-811546A03 GASKET KIT, Cylinder Head (2 required per assembly)
GASKET KIT        O - Replaced by 27-811546A04 27-811546A03
27-811546A03This part has been superseded. GASKET KIT O - Replaced by 27-811546A04
(more info)
    UnavailableUnavailable Parts
GASKET KIT Cylind 27-811546A04 27-811546A04
27-811546A04OEM Part 27-811546A04 - Gasket Kit (more info) About Mercury Marine $188.75 $188.75 Add to shopping cart
Available to order:
Usually ships
within 8 days
#38 17-843931 PIN, Dowel, Cylinder Head (4 required per assembly)
PIN Dowel 17-843931  
17-843931OEM Part 17-843931 - Pin -Dowel (more info) About Mercury Marine $8.90 $8.90 Add to shopping cart
Available to order:
Usually ships
within 8 days
#39 54-843142 J CLIP (1 required per assembly)
J CLIP 54-843142  
54-843142OEM Part 54-843142 - J Clip (more info) About Mercury Marine $3.60 $3.60 Add to shopping cart
Available to order:
Usually ships
within 8 days
#40 12-45176 WASHER, (.453 x .812 x .105) Stainless Steel (1 required per assembly)
WASHER (.453 x .8 12-45176 12-45176
12-45176OEM Part 12-45176 - Washer - Priced Individually (more info) About Mercury Marine $1.10 $1.10 Add to shopping cart
10+ in stock. Explain stock levels
Washer 18-4858-9
18-4858-9OEM Match 18-4858-9 - Washer, 12-45176, 10PK (more info) About Sierra Marine $27.22 $17.96 Add to shopping cart
2 in stock. Explain stock levels
#41 10-99204 SCREW, (.437-14 x 1.00) Stainless Steel (1 required per assembly)
SCREW (.437-14 x 10-99204 10-99204
10-99204OEM Part 10-99204 - Screw (more info) About Mercury Marine $3.60 $3.60 Add to shopping cart
1 in stock. Explain stock levels
#- 27-843073A03 GASKET/SEAL SET, Engine Overhaul (1 required per assembly) - NOTE: See Gasket/Seal Set - Engine Overhaul Section For Complete Parts Listing
GASKET/SEAL SET   O - Replaced by 27-843073A06  
27-843073A03This part has been superseded. GASKET/SEAL SET O - Replaced by 27-843073A06
(more info)
    UnavailableUnavailable Parts
GASKET/SEAL SET E 27-843073A06 27-843073A06
27-843073A06OEM Part 27-843073A06 - Gasket/Seal Set (more info) About Mercury Marine $928.01 $928.01 Add to shopping cart
Available to order:
Usually ships
within 8 days
#- 841178A 1 PARTIAL ENGINE ASSEMBLY (1 required per assembly)
PARTIAL ENGINE AS 841178A 1  
841178A 1OEM Part 841178A 1 - Partial - 525 Efi (more info) About Mercury Marine $16,767.20 $16,767.20 Add to shopping cart
Available to order:
Usually ships
within 8 days