🔎 Mercury 25 H.P. LIGHTNING (3 CYL.) (INTL. ONLY) Reference Library — Exploded parts diagrams (19 diagrams), specifications, common issues, and maintenance checklist.
The Mercury 25 H.P. LIGHTNING (3 CYL.) (INTL. ONLY) is a 4-Stroke, Inline 3-Cylinder, EFI outboard motor. Commonly used on jon boats, pontoons, and mid-size utility craft.
Quick Reference Specifications
| Specification |
Value |
| Engine Type |
4-Stroke, Inline 3-Cylinder, EFI |
| Horsepower |
25 HP |
| Displacement |
526 cc |
| Bore x Stroke |
61 mm x 57 mm |
| Spark Plug (Type & Gap) |
NGK BKR6E |
| Engine Oil Capacity |
1.8 L (1.9 quart) |
| Recommended Engine Oil |
SAE 25W-40 Synthetic Blend Mercury FC-W |
| Gear Case Oil Capacity |
280-350 mL (9.5-12 fl oz) |
| Idle Speed (in gear) |
700 ± 50 RPM (in gear) |
| Full Throttle RPM Range |
5000-6000 |
| Fuel |
Unleaded Gasoline, 87 Octane min. |
Always verify specifications against your owner's manual for your specific serial number range.
Common Issues & Recommended Parts
Below are common maintenance scenarios for the Mercury 25 H.P. LIGHTNING (3 CYL.) (INTL. ONLY):
-
Water Pump / Overheating: If the tell-tale stream is weak or absent, the water pump impeller likely needs replacement. Inspect annually or every 100 hours. → Recommended: Water Pump Impeller Kit
-
Engine Oil / Maintenance Light: 4-stroke engines require regular oil and filter changes. Use marine-grade oil rated for your engine. Change every 100 hours or annually. → Recommended: Oil Filter, Engine Oil
-
Fuel Injector Issues (EFI models): Rough idle or misfires may indicate clogged fuel injectors. Use fuel stabilizer and clean injectors periodically. → Recommended: Fuel Injector, Fuel Filter
-
Gear Case Oil Leak: Check lower unit seals if gear oil appears milky (water contamination). Replace seals and gaskets during lower unit service. → Recommended: Lower Unit Seal Kit, Drain Plug Gaskets
-
Anode Corrosion: Inspect sacrificial anodes regularly, especially in saltwater. Replace when 50% depleted to protect against galvanic corrosion. → Recommended: Zinc/Aluminum Anode Kit
Parts Diagrams & OEM Part Numbers
Expand the sections below to view detailed exploded parts diagrams and find the exact OEM replacement components for your Mercury 25 H.P. LIGHTNING (3 CYL.) (INTL. ONLY).
▶CARBURETOR (38 parts)
| Ref |
OEM Part # |
Part Name |
| - |
800-819240A6 |
POWERHEAD ASSEMBLY |
| 1 |
1300-852551T1 |
CARBURETOR (FO-3D) |
| 2 |
19-FO16128 |
PLUG |
| 3 |
809442 |
SHUTTER, Throttle |
| 4 |
10-809441 |
SCREW, Shutters |
| 5 |
809446 |
E-RING, Throttle Linkage |
| 6 |
FO8805 |
SPRING, Choke Friction |
| 7 |
FO4784 |
BALL |
| 8 |
809624 |
NOZZLE, Main |
| 9 |
17-FO13944 |
PIN |
| 10 |
891730A01 |
FLOAT, Fuel Bowl |
| 11 |
27-FO15623 |
GASKET |
| 12 |
27-FO2510 |
GASKET, Fuel Bowl |
| 13 |
FO15366 |
BOWL, Fuel |
| 14 |
1399-5128 |
SCREW |
| 15 |
1395-6359 |
JET, (.052) (7500 - 10000 FT.) |
| 16 |
F10265 |
NEEDLE, Inlet Comment: (NOTE: DO NOT REMOVE INLET SEAT) |
| 17 |
F10344 |
SHUTTER, Choke |
| 18 |
F10268 |
SCREW |
| 19 |
24-27160 |
SPRING |
| 20 |
F10275 |
SCREW |
| 21 |
809625 |
JET (.046)-THROTTLE |
| 22 |
854005 |
ELBOW, Fuel |
| 23 |
809440 |
SHAFT AND LEVER, Choke |
| 24 |
809439 |
SHAFT AND LEVER, Throttle |
| 25 |
1399-5225 |
JET, Main (.054), IDLE AIR BLEED |
| 26 |
24-F10350 |
SPRING, Throttle Shaft |
| 27 |
809445 |
SPRING, Idle Speed |
| 28 |
809444 |
SCREW, Idle Speed |
| 29 |
F10290 |
LINKAGE, Throttle |
| 30 |
F10242 |
WASHER |
| 31 |
809443 |
WIRE, Throttle Shaft |
| 32 |
27-F715906 |
GASKET, Carburetor Mount |
| 33 |
F681677 |
INSERT, Choke Rod |
| 34 |
F286547 |
KNOB, Choke |
| 35 |
23-F197319 |
BUSHING |
| 36 |
819154 |
ROD, Choke |
| 37 |
830569 |
RETAINER, Choke Rod |
▶CLAMP BRACKETS (29 parts)
| Ref |
OEM Part # |
Part Name |
| 1 |
1400-850073T4 |
BRACKET, Stern (PORT) Comment: (MARINER) |
| 2 |
1400-850073T5 |
BRACKET, Stern (STARBOARD) Comment: (MARINER) |
| 3 |
12-20553 |
WASHER, (.406 x .734 x .063) |
| 4 |
11-F7026 |
NUT, (.375-16) (.375-16) |
| 5 |
10-832820 |
SCREW (.250-20 X 3.00)-MOUNTING |
| 6 |
12-8M0204649 |
WASHER, (.281 x .500 x .060) Stainless Steel (THIN)-MOUNTING |
| 7 |
12-67983 |
WASHER |
| 8 |
11-8267118 |
NUT, (.250-20), MOUNTING |
| 9 |
10-4000332 |
SCREW, (M6 x 35) |
| 10 |
12-8M0204649 |
WASHER, (.281 x .500 x .060) Stainless Steel |
| 11 |
23-852963 |
SPACER |
| 12 |
830564 |
HANDLE, Carrying |
| 13 |
10-826248 |
SCREW, Stern Bracket |
| 14 |
17-24198 |
PIN, Roll |
| 15 |
F424075T2 |
HANDLE, Clamp Screw Comment: (MARINER) |
| 16 |
F24074 |
FOOT, Stern Bracket Screw |
| 17 |
10-69022 |
SCREW, (#10-32 x .500) Stainless Steel |
| 18 |
851924A2 |
PIN ASSEMBLY, Tilt - Stern Bracket |
| 19 |
17-38489 |
PIN, Roll |
| 20 |
24-F286461 |
SPRING |
| 21 |
851929 |
HANDLE, Lock Bar |
| 22 |
850185 |
BOLT, Pivot - Stern Bracket (.375-16 X 7.375) |
| 23 |
17-819707 |
PIN, Tilt Lock (.250-20) |
| 24 |
826251 |
LEVER, Tilt Lock |
| 25 |
10-F286422-1 |
SCREW, (.312-18 Special) (.312-18) |
| 26 |
13-69150 |
WAVE WASHER |
| 27 |
F429541 |
LOCK, Tilt |
| 28 |
23-819226 |
SPACER, Tilt Lock |
| 29 |
24-F286544-1 |
SPRING, Tilt Lock |
▶COWLING (28 parts)
| Ref |
OEM Part # |
Part Name |
| 1 |
100-819135A5 |
TOP COWL ASSEMBLY Comment: (WITHOUT DECALS) (MERCURY) |
| 2 |
819447 |
BAFFLE |
| 3 |
819130 |
BRACKET, Front |
| 4 |
819371 |
RETAINER, Rear Cowl |
| 5 |
10-835499 |
SCREW (#8-32 X .440) |
| 6 |
8,13-26995 |
LOCKWASHER, Stainless Steel |
| 7 |
8-32,11-850042 |
NUT |
| 8 |
23-F681759 |
ROLLER, Latch |
| 9 |
10-F681026 |
SCREW (SPECIAL)-LATCH ROLLER |
| 10 |
11-8M0207776 |
NUT, (.250-20) Stainless Steel |
| 11 |
12-F8155 |
WASHER |
| 12 |
37-854207A1 |
DECAL SET, Top Cowl Comment: (MARINER) (SHIFT-FRONT-REAR-PORT-STBD) |
| 13 |
100-835495A5 |
BOTTOM COWL ASSEMBLY Comment: (MARINER) |
| 14 |
38-8192814 |
PLATE, Front |
| 15 |
F392756 |
SEAL, Top Of Bottom Cowl (4.075 FT. BULK) (CUT 3.783 FT.) |
| 16 |
827895 |
SEAL, Bottom Cowl |
| 17 |
23-812707 |
BUSHING |
| 18 |
854004A2 |
HANDLE ASSEMBLY, Cowl Latch Comment: (MARINER) |
| 19 |
13-F2047 |
WASHER, Wave |
| 20 |
8M0001081 |
CAM, Latch Shaft |
| 21 |
12-71055 |
WASHER |
| 22 |
13-26992 |
LOCKWASHER, (.250) Stainless Steel |
| 23 |
10-28635 |
SCREW, (.250-20 x .620) Stainless Steel |
| 24 |
10-8M0204741 |
SCREW, (M6 x 20) Stainless Steel |
| 25 |
22-8M0182334 |
CONNECTOR, Fuel - Brass |
| 26 |
25-18202 |
GROMMET |
| 27 |
25-93527002 |
GROMMET, Control Cable |
| 28 |
37-855577A17 |
DECAL, EPA Label Information (APPLIED TO THE TOP INSIDE OF THE TOP COWL) |
▶CRANKSHAFT AND PISTON (21 parts)
| Ref |
OEM Part # |
Part Name |
| - |
800-819240A6 |
POWERHEAD ASSEMBLY |
| 1 |
1100-817753A4 |
CAGE ASSEMBLY, Crankshaft |
| 2 |
26-8M0214939 |
SEAL, Oil |
| 3 |
10-F1914 |
SCREW, (.250-20 x .750) |
| 4 |
27-F286277 |
GASKET, Crankshaft Bearing Cage |
| 5 |
400-819044A3 |
CRANKSHAFT ASSEMBLY |
| 6 |
30-F286028 |
BEARING, Ball |
| 7 |
31-819239 |
LINER, Center Main Rollers |
| 8 |
29-819238 |
ROLLERS (16 PER STRIP) |
| 9 |
637-8477A2 |
CONNECTING ROD ASSEMBLY |
| 10 |
10-823460 |
SCREW, (M5 x 16) |
| 11 |
29-42186 |
BEARING, Needle |
| 12 |
12-8M0012297 |
BEARING, Thrust |
| 13 |
31-42076A1 |
BEARING ASSEMBLY, Roller |
| 14 |
31-8191291 |
BEARING, Main |
| 15 |
26-819214 |
SEAL, Crankshaft Lower |
| 16 |
784-9747A8 |
PISTON KIT (STANDARD) |
| 17 |
40-422021 |
LOCK RING |
| 18 |
39-18213A1 |
RING SET (2 RINGS) (STANDARD) |
| 19 |
26-819293 |
SEAL, Driveshaft Spline |
| 20 |
8193101 |
RETAINER, Driveshaft Spline Seal |
▶CYLINDER BLOCK ASSEMBLY (45 parts)
| Ref |
OEM Part # |
Part Name |
| - |
800-819240A6 |
POWERHEAD ASSEMBLY |
| 1 |
800-819240A5 |
CYLINDER ASSEMBLY |
| 2 |
10-92160 |
SCREW, (.250-20 x .750) Stainless Steel |
| 3 |
12-8M0204649 |
WASHER, (.281 x .500 x .060) Stainless Steel |
| 4 |
10-54523 |
SCREW, (.312-18 x 1.00) |
| 5 |
12-20084 |
WASHER, (.328 x .562 x .062) |
| 6 |
17-F8559 |
PIN |
| 7 |
21-426585 |
CHECK VALVE |
| 8 |
32-892024122 |
TUBING, (20.00 Feet Bulk) (CUT 2 PCS-15.00 IN.)(CUT 1 PC-12.058 IN.) |
| 9 |
16-834759 |
STUD, (.312-24 X 1.14) Special |
| 10 |
16-826590 |
STUD, (.250-20 x 1.690) |
| 11 |
834753 |
BRACKET, Throttle Stop |
| 12 |
27-809516A1 |
GASKET SET, Powerhead |
| 13 |
32-819243 |
TUBE, Water Jacket |
| 14 |
22-887801 |
ELBOW, Tell-Tale Tubing |
| 15 |
32-549507 |
HOSE (7.00 IN.)-TELL TALE |
| 16 |
27-819140 |
GASKET, Exhaust Cover |
| 17 |
819152 |
PLATE, Exhaust |
| 18 |
1000-819136T1 |
COVER, Exhaust |
| 19 |
10-819110125 |
SCREW, (.250-20 X 1.250) |
| 20 |
10-90192 |
SCREW, (.250-20 x .750) Stainless Steel, GROUND WIRE |
| 21 |
27-819498 |
GASKET, Cylinder Mount |
| 22 |
819157T1 |
TUBE, Exhaust |
| 23 |
12-8M0204649 |
WASHER, (.281 x .500 x .060) Stainless Steel |
| 24 |
13-26992 |
LOCKWASHER, (.250) Stainless Steel |
| 25 |
10-90192 |
SCREW, (.250-20 x .750) Stainless Steel |
| 26 |
1000-819137T1 |
COVER ASSEMBLY, Transfer Port |
| 27 |
22-15133 |
FITTING |
| 28 |
16-F681134 |
STUD, Interlock Lever |
| 29 |
10-90192 |
SCREW, (.250-20 x .750) Stainless Steel |
| 30 |
12-26907 |
WASHER |
| 31 |
10-F1535 |
SCREW, (.250-20 x .750) |
| 32 |
27-819143 |
GASKET, Transfer Port Cover |
| 33 |
12-8M0204690 |
WASHER, (.344 x .688 x .065) Stainless Steel |
| 34 |
10-F1882 |
SCREW, (.312-18 x 2.125) |
| 35 |
27-8191382 |
GASKET, Cylinder Head |
| 36 |
900-819145T2 |
CYLINDER HEAD |
| 37 |
27-8191391 |
GASKET, Cylinder Head Cover |
| 38 |
819134T |
COVER, Cylinder Head |
| 39 |
12-F658504 |
WASHER |
| 40 |
895338 |
THERMOSTAT, 54°C (130°F) |
| 41 |
24-819161 |
SPRING, Thermostat |
| 42 |
819439T |
COVER, Thermostat |
| 43 |
10-35386 |
SCREW, (.312-18 x 1.00) |
| 44 |
13-78968 |
LOCKWASHER, Internal (.250), GROUND SCREW |
▶FUEL SYSTEM (15 parts)
| Ref |
OEM Part # |
Part Name |
| - |
800-819240A6 |
POWERHEAD ASSEMBLY |
| 1 |
8192131 |
PUMP ASSEMBLY, Fuel |
| 2 |
27-820748A1 |
GASKET/DIAPHRAGM KIT |
| 3 |
NSS |
NOT SOLD SEPARATE, Washer |
| 4 |
10-820749 |
SCREW (#10-24 X 1.250) |
| 5 |
10-819499 |
SCREW (#10-24 X 1.625) |
| 6 |
25-38933 |
O-RING |
| 7 |
56762 |
TIE STRAP, (4.00 Inches) |
| 8 |
32-819398T |
HOSE (18.00 IN. BULK) (CUT 1.625 IN.) |
| 9 |
32-819398T |
HOSE (18.00 IN. BULK) (CUT 3.125 IN.) |
| 10 |
32-819398T |
HOSE (18.00 IN. BULK) (CUT 10.500 IN.) |
| 11 |
851934 |
COVER, Primer Bulb |
| 12 |
F681046 |
BULB, Primer |
| 13 |
32-819398T |
HOSE (18.00 IN. BULK) (CUT 11.500 IN.) |
| 14 |
35-816296Q03 |
FILTER, Fuel |
▶FUEL TANK & LINE ASSEMBLY, 6.6 GALLON (15 parts)
| Ref |
OEM Part # |
Part Name |
| 1 |
1259-859063A1 |
TANK ASSEMBLY, Fuel - Plastic 6.6 Gallon |
| 2 |
823536 |
GAUGE/CAP ASSEMBLY |
| 3 |
22-8M0175545 |
CONNECTOR ASSEMBLY |
| 4 |
25-823533 |
O-RING |
| 5 |
35-823534 |
SCREEN |
| 6 |
32-877681Q8 |
LINE ASSEMBLY, Fuel (8 Feet) (.312 I.D.)(30.00 IN. & 60.00 IN.) |
| 7 |
13330Q07 |
BULB ASSEMBLY, Primer |
| 8 |
21-13331A3 |
CHECK VALVE ASSEMBLY (INLET) |
| 9 |
21-13331A4 |
CHECK VALVE ASSEMBLY (OUTLET) |
| 10 |
54-4158210 |
CLAMP, Nylon (LARGE) |
| 11 |
54-41582Q7 |
CLAMP, Nylon (SMALL) |
| 12 |
22-13563Q3 |
FITTING ASSEMBLY, Fuel Line |
| 13 |
22-89771Q2 |
CONNECTOR, (.250-18) |
| 14 |
54-41582Q7 |
CLAMP, Nylon (SMALL) |
| 15 |
32-858610100 |
HOSE, (100.00 Feet Bulk), CUT AS REQ'D |
▶GEAR HOUSING ASSEMBLY, DRIVESHAFT (41 parts)
| Ref |
OEM Part # |
Part Name |
| - |
46-99157T2 |
REPAIR KIT, Water Pump |
| 1 |
1665-8669A22 |
GEAR HOUSING ASSEMBLY, Basic-Gray |
| 2 |
NSS |
NOT SOLD SEPARATE, Sleeve |
| 3 |
26-99325 |
SEAL |
| 4 |
31-41326 |
BEARING, Roller |
| 5 |
17-8M0084726 |
PIN, Dowel (.187 x .530) |
| 6 |
10-79953Q04 |
SCREW KIT, (.375-16 x .250) |
| 7 |
12-191833 |
WASHER, Fiber |
| 8 |
35-41133 |
SCREEN, Water Inlet Port |
| 9 |
10-40031112 |
SCREW, (M5 x 40) |
| 10 |
22-8M0058389 |
FITTING KIT, Magnetic, Plug Fill/Drain |
| 11 |
12-191833 |
WASHER, Fiber |
| 12 |
35-41134 |
SCREEN (STARBOARD) |
| 13 |
11-400263 |
NUT, (M5), SCREEN SCREW |
| 14 |
31-98294A1 |
BEARING ASSEMBLY, Roller |
| 15 |
NSS |
NOT SOLD SEPARATE, Cup-roller Bearing |
| 16 |
97-98432Q6 |
TRIM TAB |
| 17 |
10-4000354 |
SCREW, (M8 x 30) |
| 18 |
10-8248324 |
SCREW, (M6 x 16) |
| 19 |
10-49908 |
SCREW, (.250-28 x .750) |
| 20 |
43-98302 |
GEAR, Pinion |
| 21 |
27-993261 |
GASKET |
| 22 |
85083 |
FACE PLATE |
| 23 |
12-866451 |
WASHER |
| 24 |
28-8M0214993 |
KEY |
| 25 |
47-8M0204712 |
IMPELLER |
| 26 |
12-866451 |
WASHER |
| 27 |
25-69202 |
O-RING |
| 28 |
46-99157A02 |
PUMP ASSEMBLY, Water |
| 29 |
NSS |
NOT SOLD SEPARATE, Insert |
| 30 |
26-85090001 |
SEAL |
| 31 |
25-86203 |
O-RING |
| 32 |
12-8M0042642 |
WASHER, (.323 x .563 x .063) Stainless Steel |
| 33 |
853940 |
ROD, Gear Shift Comment: (20 IN. LONG MODELS) |
| 34 |
45-827025T |
DRIVESHAFT Comment: (20 IN. LONG MODELS) |
| 35 |
85552001 |
BOOT |
| 36 |
93878 |
RETAINER |
| 37 |
25-35276 |
O-RING, (.734 x .139) |
| 38 |
25-85594 |
O-RING, (.239 x .174) |
| 39 |
85562A2 |
SHIFT CAM |
| 40 |
17-85096 |
PIN, Drive |
▶GEAR HOUSING ASSEMBLY, PROPELLER SHAFT (25 parts)
| Ref |
OEM Part # |
Part Name |
| - |
26-85090A2 |
SEAL KIT |
| 1 |
1665-8669A22 |
GEAR HOUSING ASSEMBLY, Basic-Gray |
| 41 |
31-8M0103470 |
BEARING ASSEMBLY, Roller |
| 42 |
NSS |
NOT SOLD SEPARATE, Cup-Roller Bearing |
| 43 |
43-44213T1 |
GEAR ASSEMBLY, Forward |
| 44 |
23-85557 |
BUSHING |
| 45 |
85094 |
FOLLOWER, Cam |
| 46 |
24-38114 |
SPRING |
| 47 |
52-41040T1 |
CLUTCH |
| 48 |
17-8M0020999 |
PIN |
| 49 |
24-88680 |
SPRING |
| 50 |
44-8166231 |
PROPELLER SHAFT |
| 51 |
43-99542T |
GEAR, Reverse |
| 52 |
99906T1 |
CARRIER ASSEMBLY, Bearing |
| 53 |
31-21739 |
BEARING, Roller |
| 54 |
26-41132 |
SEAL, Oil (INNER) |
| 55 |
26-41131 |
SEAL, Oil (OUTER) |
| 56 |
25-85549 |
O-RING |
| 57 |
87293 |
PLATE |
| 58 |
10-90883 |
SCREW, (M5 x 16) |
| 59 |
12-8M0214963 |
WASHER, (.406 x .750 x .104) |
| 60 |
10-65210 |
SCREW, (.375-16 x 1.00) |
| 61 |
851281 |
THRUST HUB ASSEMBLY |
| 62 |
48-19644A5 |
PROPELLER (SS-10.375 X 13.0 RH) (VENGEANCE) |
| 63 |
11-88228 |
PROP NUT (M12 NYLON)-FOR ALUM PROPELLERS |
▶IGNITION SYSTEM (25 parts)
| Ref |
OEM Part # |
Part Name |
| - |
819155A2 |
STATOR ASSEMBLY (COMPLETE) |
| 1 |
300-819155T |
PLATE, Stator |
| 2 |
300-850899T1 |
MODULE KIT, Ignition |
| 3 |
86-8M0204694 |
CONNECTOR (SERVICE ONLY) |
| 4 |
10-824353 |
SCREW (#8-32 X .750)-IGN MODULE MOUNT |
| 5 |
84-12479A60 |
CABLE ASSEMBLY, Modules To Harness |
| 6 |
85-63709A1 |
BOOT/TERMINAL KIT |
| 7 |
1,2,3,20117A1 |
MARKER SET, Ignition Cables |
| 8 |
F681091 |
NUT (SPECIAL)-FLYWHEEL |
| 9 |
200-824380T4 |
FLYWHEEL |
| 10 |
87-824440A14 |
SWITCH ASSEMBLY, Stop |
| 11 |
824466A3 |
COVER ASSEMBLY, Stop Switch |
| 12 |
824915 |
BEZEL, Stop Switch Cover |
| 13 |
87-826214A1 |
SWITCH ASSEMBLY, Emergency Stop |
| 14 |
11-855594 |
NUT (SPECIAL)-STOP SWITCH SLEEVE |
| 15 |
879104 |
LANYARD ASSEMBLY |
| 16 |
28-F458498-1 |
KEY, Crankshaft/Flywheel |
| 17 |
8278961 |
CAM, Throttle |
| 18 |
84-821375A44 |
CABLE ASSEMBLY, Ground |
| 19 |
54-816311T |
TIE STRAP, (8.00 Inches) |
| 20 |
10-824358 |
SCREW, (#10-24 x .500) (#10-24 X .500)-STATOR PLATE |
| 21 |
33-896329874 |
SPARK PLUG (RFI) (CHAMPION # RL82C) |
| 22 |
84-79138A93 |
HARNESS ASSEMBLY, Engine Stop |
| 23 |
13541 |
PLUG, Male |
| 24 |
54-831275 |
CLAMP |
▶PAINT (1 parts)
| Ref |
OEM Part # |
Part Name |
| - |
92-82582312 |
PAINT, Silver (.5 Ounces) (15 ML) BRUSH BOTTLE (BOX OF 12) GEAR SHIFT HANDLE ONLY-MERCURY AND MARINER COWL ONLY-MARINER |
▶REED PLATE/MANIFOLD ASSEMBLY (12 parts)
| Ref |
OEM Part # |
Part Name |
| - |
800-819240A6 |
POWERHEAD ASSEMBLY |
| 1 |
819150A4 |
MANIFOLD ASSEMBLY, Intake |
| 2 |
21-426982 |
CHECK VALVE |
| 3 |
16-826622 |
STUD, (.250-20 x .910) (.250-20 X .910) WITH DRI LOK |
| 4 |
11-20890 |
NUT, (.250-20), CARBURETOR MOUNT |
| 5 |
10-819110125 |
SCREW, (.250-20 X 1.250) (.250-20 X 1.250) |
| 6 |
34-827308 |
REED |
| 7 |
34-827307 |
STOP, Reed |
| 8 |
10-819074 |
SCREW WITH LOCKWASHER, (#6-32 X .312) (#6-32 X .312) |
| 9 |
27-819142 |
GASKET, Reed Plate |
| 10 |
819153T |
PLATE, Reed |
| 11 |
27-819141 |
GASKET, Intake Manifold |
▶REMOTE CONTROL LINKAGE, DESIGN I (32 parts)
| Ref |
OEM Part # |
Part Name |
| 1 |
827889A2 |
STEERING KIT, Remote |
| 2 |
71565 |
TUBE, Cable Guide |
| 3 |
11-8M0041651 |
NUT, (.875-14) |
| 4 |
14-42100 |
TAB WASHER |
| 5 |
827890 |
BRACKET, Cable Tube |
| 6 |
F676541-2 |
LOCK, Tilt |
| 7 |
827889A2 |
LINK, Steering |
| 8 |
12-37828 |
WASHER, (.390 x .625 x .062) Stainless Steel |
| 9 |
11-8M0204726 |
NUT, (.375-24) |
| 10 |
850185 |
BOLT, Pivot - Stern Bracket (.375-16 X 7.375) |
| 11 |
11-F7026 |
NUT, (.375-16) (.375-16) |
| 12 |
54-816311T |
TIE STRAP, (8.00 Inches) |
| 13 |
10-90072 |
SCREW, (.375-24 x 1.750) |
| 14 |
23-F522359 |
SPACER |
| 15 |
23-F84215 |
SPACER |
| 16 |
830771A9 |
CONVERSION KIT, Remote Control Comment: (MARINER) (DESIGN I) |
| 17 |
18-26811 |
COTTER PIN |
| 18 |
12-35462 |
WASHER, (.2656 x .625 x .0625) Stainless Steel |
| 19 |
16-828819 |
STUD, Throttle Control |
| 20 |
10,13-F8058 |
LOCKWASHER, Internal |
| 21 |
8191481 |
LEVER, Throttle |
| 22 |
10-32,11-8M0204718 |
NUT, |
| 23 |
25-93527002 |
GROMMET |
| 24 |
10-830772 |
SCREW (SPECIAL) |
| 25 |
855791A3 |
ANCHOR ASSEMBLY, Remote Steering Cable Comment: (MARINER) |
| 26 |
38-8192812 |
DECAL, Front Plate |
| 27 |
10-852453 |
SCREW, (#10-24 x .560) |
| 28 |
10-24,11-F7009 |
NUT, |
| 29 |
13-72521 |
LOCKWASHER, Internal Tooth |
| 30 |
10-38837 |
SCREW, (.312-18 x 1.12) |
| 31 |
830006T2 |
ARM, Remote Steering Comment: (MERCURY) |
| 32 |
19-48323 |
PLUG |
▶REMOTE CONTROL LINKAGE, DESIGN II (33 parts)
| Ref |
OEM Part # |
Part Name |
| 1 |
827889A2 |
STEERING KIT, Remote |
| 2 |
71565 |
TUBE, Cable Guide |
| 3 |
11-8M0041651 |
NUT, (.875-14) |
| 4 |
14-42100 |
TAB WASHER |
| 5 |
827890 |
BRACKET, Cable Tube |
| 6 |
F676541-2 |
LOCK, Tilt |
| 7 |
827889A2 |
LINK, Steering |
| 8 |
12-37828 |
WASHER, (.390 x .625 x .062) Stainless Steel |
| 9 |
11-8M0204726 |
NUT, (.375-24) |
| 10 |
850185 |
BOLT, Pivot - Stern Bracket (.375-16 X 7.375) |
| 11 |
11-F7026 |
NUT, (.375-16) (.375-16) |
| 12 |
54-816311T |
TIE STRAP, (8.00 Inches) |
| 13 |
10-90072 |
SCREW, (.375-24 x 1.750) |
| 14 |
23-F522359 |
SPACER |
| 15 |
23-F84215 |
SPACER |
| 16 |
830771A9 |
CONVERSION KIT, Remote Control Comment: (MARINER) (DESIGN II) |
| 17 |
18-26811 |
COTTER PIN |
| 18 |
12-35462 |
WASHER, (.2656 x .625 x .0625) Stainless Steel |
| 19 |
16-828819 |
STUD, Throttle Control |
| 20 |
10,13-F8058 |
LOCKWASHER, Internal |
| 21 |
8191481 |
LEVER, Throttle |
| 22 |
10-32,11-8M0204718 |
NUT, |
| 23 |
25-93527002 |
GROMMET |
| 24 |
11-8M0207776 |
NUT, (.250-20) Stainless Steel |
| 25 |
855791A3 |
ANCHOR ASSEMBLY, Remote Steering Cable Comment: (MARINER) |
| 26 |
38-8192812 |
DECAL, Front Plate |
| 27 |
10-852453 |
SCREW, (#10-24 x .560) |
| 28 |
10-24,11-F7009 |
NUT, |
| 29 |
13-72521 |
LOCKWASHER, Internal Tooth |
| 30 |
10-38837 |
SCREW, (.312-18 x 1.12) |
| 31 |
830006T2 |
ARM, Remote Steering Comment: (MERCURY) |
| 32 |
19-48323 |
PLUG |
| 33 |
23-855648 |
SLEEVE |
▶SHIFT LINKAGE (39 parts)
| Ref |
OEM Part # |
Part Name |
| - |
800-819240A6 |
POWERHEAD ASSEMBLY |
| 1 |
F681490 |
STOP, Starter Pulley Interlock |
| 2 |
F681003-1 |
ARM, Starter Interlock |
| 3 |
12-F8143 |
WASHER |
| 4 |
10-48408 |
SCREW, (#10-16 x .500) |
| 5 |
F681263-1 |
LINK, Starter Interlock |
| 6 |
F681742 |
LEVER, Intermediate Interlock |
| 7 |
10-32,11-20110 |
NUT, |
| 8 |
24-F681424 |
SPRING, Interlock Lever |
| 9 |
16-F681134 |
STUD, Interlock Lever |
| 10 |
816514 |
BEARING, Spark Control |
| 11 |
16-826590 |
STUD, (.250-20 x 1.690) (.250-20 X 1.690) |
| 12 |
824357 |
LEVER, Neutral Speed Interlock |
| 13 |
11-8M0207776 |
NUT, (.250-20) Stainless Steel |
| 14 |
819159 |
ROD, Interlock |
| 15 |
10-819625 |
SCREW |
| 16 |
F286685 |
CONNECTOR, Gear Shift Rod |
| 17 |
16-F98273 |
STUD |
| 18 |
855621T |
LEVER, Gear Shift |
| 19 |
17-25319 |
PIN, (.125 x 0.75 Inches) |
| 20 |
F286871T |
PIN, Gear Shift Lever |
| 21 |
23-26841 |
BUSHING |
| 22 |
8193781 |
ROD, Upper Gear Shift |
| 23 |
10-F1976 |
SCREW, (#10-24 x .500) |
| 24 |
12-89302 |
WASHER, (.203 x .406 x .040) |
| 25 |
24-39627 |
SPRING |
| 26 |
824994 |
SPRING, Plate |
| 27 |
850388 |
LINK, Shift Lever |
| 28 |
13-F8048 |
WASHER, Bowed |
| 29 |
10,13-26996 |
LOCKWASHER, Stainless Steel |
| 30 |
10,13-F8058 |
LOCKWASHER, Internal |
| 31 |
850386 |
SHAFT, Shift Handle |
| 32 |
850387A1 |
LEVER ASSEMBLY, Detent Cam |
| 33 |
16-846345 |
STUD, (#10-32 x .750) |
| 34 |
17-25905 |
PIN |
| 35 |
10-42813 |
SCREW, (#10-32 X .380) (#10-32 X .380) |
| 36 |
852545 |
HANDLE, Shift |
| 37 |
12-4002314 |
WASHER |
| 38 |
10-15124 |
SCREW, (#10-32 x .750) |
▶STARTER REWIND COMPONENTS (24 parts)
| Ref |
OEM Part # |
Part Name |
| - |
800-819240A6 |
POWERHEAD ASSEMBLY |
| 1 |
F6814081 |
HOUSING, Starter |
| 2 |
37-825149A1 |
DECAL KIT, Shift to Neutral |
| 3 |
10-90192 |
SCREW, (.250-20 x .750) Stainless Steel |
| 4 |
23-F681405T |
INSERT, Starter Housing |
| 5 |
F681428 |
INSERT, Starter Rope |
| 6 |
53-818853 |
RING, Retaining |
| 7 |
819245T1 |
BRACKET |
| 8 |
11-8M0207776 |
NUT, (.250-20) Stainless Steel |
| 9 |
10-98254 |
SCREW, (.250-20 x .620) |
| 10 |
24-F681970 |
SPRING, Starter Rewind |
| 11 |
42034A2 |
PULLEY ASSEMBLY, Starter Rewind |
| 12 |
19-817362 |
CAP |
| 13 |
26-124941 |
SEAL, Pulley Bearing |
| 14 |
50-12066T03 |
ROPE (64.00/67.00 IN.) |
| 15 |
F681592 |
RETAINER, Starter Pulley |
| 16 |
10-48408 |
SCREW, (#10-16 x .500) |
| 17 |
10-819625 |
SCREW |
| 18 |
FA681630T |
SUPPORT ASSEMBLY, Handle |
| 19 |
8302821 |
PLATE, Handle Support |
| 20 |
F6818741 |
FASTENER, Handle Support Plate |
| 21 |
10-F2210 |
SCREW, (.250-14 x .500) |
| 22 |
F681132 |
HANDLE, Rope |
| 23 |
F681817 |
RETAINER, Rope Handle |
▶SWIVEL BRACKET AND DRIVESHAFT HOUSING (40 parts)
| Ref |
OEM Part # |
Part Name |
| 1 |
12-F286011 |
WASHER, Swivel Bracket |
| 2 |
1400-850049A4 |
SWIVEL BRACKET KIT Comment: (MARINER) |
| 3 |
23-F681169 |
BEARING (1.125 IN.) (TOP) |
| 4 |
23-F286169 |
BEARING (1.750 IN.) (BOTTOM) |
| 5 |
22-F213274 |
FITTING |
| 6 |
F681631 |
SHOE, Friction |
| 7 |
54-F286573-1 |
CLAMP, Steering Friction |
| 8 |
10-F1820 |
SCREW, (.250-20 x 1.375) |
| 9 |
12-8M0207778 |
WASHER |
| 10 |
11-F1608 |
NUT, (.250-20) (.250-20) |
| 11 |
17-F1794 |
PIN, Spring |
| 12 |
17-F8538 |
PIN, Spring |
| 13 |
23-26856 |
BUSHING |
| 14 |
833156 |
LEVER, Reverse Lock |
| 15 |
820095A2 |
LEVER ASSEMBLY, Reverse Lock Intermediate |
| 16 |
23-F536813 |
BUSHING |
| 17 |
12-F2037 |
WASHER |
| 18 |
F286827 |
LEVER, Reverse Lock Release |
| 19 |
17-F1806 |
PIN, Groove |
| 20 |
12-F2037 |
WASHER |
| 21 |
37-8180291 |
DECAL, Fuel Mix |
| 22 |
37-8302531 |
DECAL, Tilt Release |
| 23 |
852528 |
LINK, Reverse Lock Lever |
| 24 |
24-F286300 |
SPRING, Reverse Lock |
| 25 |
850259 |
LOCK, Reverse |
| 26 |
8301111 |
BRACKET, Shallow Water Drive |
| 27 |
FA1844 |
SCREW KIT, (.250-20 x 2.375) (.250-20 X 2.375) |
| 28 |
13-26992 |
LOCKWASHER, (.250) Stainless Steel |
| 29 |
11-64015 |
NUT, (.250-20) |
| 30 |
819320T2 |
BRACKET, Shock Mount Lower Comment: (MARINER) |
| 31 |
826361T3 |
SPACER ASSEMBLY Comment: (20 IN. LONG MODELS) (MARINER) |
| 32 |
17-8M0084726 |
PIN, Dowel (.187 x .530) Comment: (20 IN. LONG MODELS) |
| 33 |
10-65210 |
SCREW, (.375-16 x 1.00) Comment: (20 IN. MODELS) |
| 34 |
12-8M0214963 |
WASHER, (.406 x .750 x .104) Comment: (20 IN. LONG MODELS) |
| 35 |
32-8191491 |
LINE, Water Inlet Comment: (20 IN. LONG MODELS) |
| 36 |
F286914-1 |
SLEEVE, Water Inlet Line |
| 37 |
8193192 |
SHOCK MOUNT, Lower |
| 38 |
1500-819215T4 |
HOUSING ASSEMBLY, Driveshaft Comment: (MARINER) |
| 39 |
25-F46899-1 |
COVER |
| 40 |
F517347 |
SHOCK MOUNT, Upper |
▶TILLER HANDLE/LINKAGE (47 parts)
| Ref |
OEM Part # |
Part Name |
| - |
800-819240A6 |
POWERHEAD ASSEMBLY |
| 1 |
851928 |
SHAFT, Throttle Control |
| 2 |
23-26841 |
BUSHING |
| 3 |
FA343178 |
RETAINER KIT, Steering Shaft |
| 4 |
10-832794 |
SET SCREW, (.250-28 X .250) (.250-28 X .250) |
| 5 |
17-29908 |
PIN |
| 6 |
43-8180091 |
GEAR, Steering Shaft |
| 7 |
17-F1807 |
PIN, Groove |
| 8 |
10-823595 |
SCREW (SPECIAL) |
| 9 |
24-F286868 |
SPRING, Steering Handle Stop |
| 10 |
23-26856 |
BUSHING |
| 11 |
F286490T |
STOP, Steering Handle |
| 12 |
835373A7 |
BRACKET ASSEMBLY, Steering Arm Comment: (MARINER) |
| 13 |
10-828815 |
SCREW, (.250-20 x 1.750) (.250-20 X 1.750) |
| 14 |
19-F286539 |
BUMPER |
| 15 |
11-8M0207776 |
NUT, (.250-20) Stainless Steel |
| 16 |
13-72521 |
LOCKWASHER, Internal Tooth |
| 17 |
10-38837 |
SCREW, (.312-18 x 1.12) |
| 18 |
F2862241 |
INSERT, Steering Handle Pivot |
| 19 |
23-812707 |
BUSHING |
| 20 |
12-F286220 |
WASHER, Steering Handle |
| 21 |
23-26856 |
BUSHING |
| 22 |
819279T2 |
HANDLE, Steering Comment: (MARINER) |
| 23 |
25-8M0204645 |
O-RING, (.796 x .139) (LARGE) |
| 24 |
25-38101 |
O-RING, (.674 x .103) (SMALL) |
| 25 |
37-F712894 |
DECAL, Speed/Shift Indicator |
| 26 |
828406A1 |
HANDLE/GRIP ASSEMBLY, Throttle |
| 27 |
828406 |
GRIP, Throttle/Steering Handle |
| 28 |
17-72255 |
PIN, Roll |
| 29 |
819227 |
WEDGE, Steering Handle |
| 30 |
23-97896 |
BUSHING |
| 31 |
10,13-F8058 |
LOCKWASHER, Internal |
| 32 |
10-F1829 |
SCREW, (#10-24 x .875) |
| 33 |
F4878161 |
BEARING |
| 34 |
819160 |
SHAFT, Steering Handle |
| 35 |
832759 |
STOP, Throttle |
| 36 |
10-832794 |
SET SCREW, (.250-28 X .250) (.250-28 X .250) |
| 37 |
817751A8 |
BRACKET ASSEMBLY, Steering Comment: (MARINER) |
| 38 |
22-F523274 |
FITTING, Grease |
| 39 |
10-823594 |
SCREW (SPECIAL)-PIVOT |
| 40 |
11-82670911 |
NUT, (.312-24) Stainless Steel |
| 41 |
12-F286282 |
WASHER (SPECIAL) |
| 42 |
819148 |
LEVER, Magneto Control |
| 43 |
23-F183813 |
BEARING, Control Lever |
| 44 |
16-834759 |
STUD, (.312-24 X 1.14) Special (.312-24 X 1.140) |
| 45 |
826846 |
LINK, Throttle Shaft |
| 46 |
824142T |
LINK, Throttle Cam |
▶TOOLS, SPECIAL (1 parts)
| Ref |
OEM Part # |
Part Name |
| - |
92-816391A4 |
GREASE |
100-Hour / Annual Service Checklist
Regular maintenance keeps your Mercury 25 H.P. LIGHTNING (3 CYL.) (INTL. ONLY) running reliably season after season. Most of these tasks can be performed with basic tools and the factory service manual.
- Replace water pump impeller and inspect wear plate
- Change engine oil and oil filter (check drain plug washer)
- Replace spark plugs and check ignition timing
- Drain and refill lower unit gear oil; inspect for water contamination
- Inspect fuel lines, primer bulb, and fuel filter for deterioration
- Check and replace sacrificial anodes (zinc or aluminum)
- Inspect propeller for damage; check shaft seal and cotter pin
- Check valve clearance (refer to service manual for specifications)
- Lubricate all grease points (steering, tilt tube, shift linkage)
- Inspect control cables and throttle/shift linkage for smooth operation
-
Pro Tip: Always flush the engine with fresh water after saltwater use — even a quick 10-minute flush significantly extends component life.
-
Pro Tip: Use fuel stabilizer in the tank before winter storage, and fog the cylinders to prevent internal corrosion during extended periods of non-use.
