NGK Spark Plugs: MerCruiser & Marine Conversions

NGK Spark Plugs: MerCruiser & Marine Conversions

266 spark plug applications from NGK's catalogue, for the inboard and sterndrive engines we supply parts for. Each line gives the plug NGK specifies, the premium upgrade where one exists, and the electrode gap. Plug codes shown as links go straight to that plug on our shop.

Check the gap before you fit. Plugs are not always gapped correctly out of the box, and the wrong gap causes misfire and hard starting. Where a resistor plug is specified, fit a resistor plug — a non-resistor substitute can interfere with a tacho, sounder or engine electronics.

Mercruiser 175 applications

Model Engine / details NGK plug Premium upgrade Gap
120 YR5 YR5IX 0.9 mm
140 YR5 YR5IX 0.9 mm
165 YR5 YR5IX 0.9 mm
190 XR5 XR5IX 0.9 mm
198 YR5 YR5IX 0.9 mm
215 AR6FS 0.8 mm
225 AR6FS 0.8 mm
225 XR5 XR5IX 0.9 mm
228 YR5 YR5IX 0.9 mm
233 AR6FS 0.8 mm
255 AR6FS 0.8 mm
3.0L MPI ECT TR5 TR5IX 1.1 mm
325 BUE
350 MAG ECT ITR4A15 1.5 mm
350 MAG MPI 2006-2000 TR5 TR5IX 0.9 mm
350 MAG MPI 2007 IZFR7M 0.8 mm
350 MAG MPI GEN+ TR55 TR55IX 1.5 mm
350 MAG MPI GEN+ HORIZON TR5 TR5IX 0.9 mm
350 MAG MPI GEN+ HORIZON TR55 TR55IX 1.5 mm
350 MAG MPI HORIZON 2007 IZFR7M 0.8 mm
377 MAG ECT ITR4A15 1.5 mm
4.3L MPI ECT ITR4A15 1.5 mm
4.3L MPI GEN+ TR55 TR55IX 1.5 mm
4.3L TKS TR5 TR5IX 1.1 mm
4.5L BRIZO BPR5EFS-13 TR55IX 1.3 mm
496 MAG TR55 TR55IX 1.5 mm
496 MAG HO TR55 TR55IX 1.5 mm
5.0L YR5 YR5IX 0.9 mm
5.0L MPI ECT ITR4A15 1.5 mm
5.0L MPI GEN+ TR55 TR55IX 1.5 mm
5.0LX YR5 YR5IX 0.9 mm
5.7L 2007 IZFR7M 0.8 mm
5.7L HORIZON DTS ECT ITR4A15 1.5 mm
5.7L MPI ECT ITR4A15 1.5 mm
6.2L HORIZON DTS ECT ITR4A15 1.5 mm
8.1S HO 2006-2000 TR55 TR55IX 1.5 mm
8.1S HO 2007 IZFR7M 0.8 mm
8.1S HORIZON 2006-2000 TR55 TR55IX 1.5 mm
8.1S HORIZON 2007 IZFR7M 0.8 mm
888 AR6FS 0.8 mm
898, 200 YR5 YR5IX 0.9 mm
BIG BLOCK 325 V: 2 762 442 on R5673-8 0.9 mm
BIG BLOCK 330, 340 BR6FS 0.9 mm
BIG BLOCK 330, B-W, 370 BR6FS 0.9 mm
BIG BLOCK 350 R5673-8 0.9 mm
BIG BLOCK 390 BPR8ES BPR8EIX 0.9 mm
BIG BLOCK 400 Jet BR6FS 0.9 mm
BIG BLOCK 454 EFI MPI BR6FS 1.0 mm
BIG BLOCK 454 Mag MPI V: 0L 002 200 on BR6FS 0.9 mm
BIG BLOCK 454 MPI BR6FS 1.0 mm
BIG BLOCK 7.4 · 7.4L Incl. EFI 11.2 mm reach plugs BR6FS 1.0 mm
BIG BLOCK 7.4 · 7.4L MPI BR6FS 1.0 mm
BIG BLOCK 7.4 · 7.4L MPI BPR6EFS BPR6EFIX-10 1.1 mm
BIG BLOCK 8.1 · 8.1S HO, Horizon · 00→06 PTR5D-13 TR5AI-13 1.5 mm
BIG BLOCK 8.2 · 8.2L (Incl. MPI) BR6FS 1.0 mm
BLACK SCORPION 5.7L 2006-2000 TR55 TR55IX 1.5 mm
BLACK SCORPION 5.7L 2007 IZFR7M 0.8 mm
BLACK SCORPION MX 6.2 2006-2000 TR5 TR5IX 0.9 mm
BLACK SCORPION MX 6.2 2006-2000 TR55 TR55IX 1.5 mm
BLACK SCORPION MX 6.2 2007 IZFR7M 0.8 mm
CHEVROLET 325 V: 3 043 030 on R5673-8 0.9 mm
CHEVROLET 454 MAG Alpha, Bravo, EFI, MPI, · 88→01 BR6FS 0.9 mm
CHEVROLET 460 Cyclone, 475 Turbo R5673-8 0.9 mm
CHEVROLET 496 Mag (Incl. HO) PTR5D-13 TR5AI-13 1.5 mm
CHEVROLET 502 Mag, EFI, MPI · 90→01 BR6FS 1.0 mm
CHEVROLET 7.4 · 7.4L MPI (L29) · 98→00 BPR6EFS BPR6EFIX-10 1.1 mm
CHEVROLET 7.4 · 7.4L, 7.4LX, Alpha, Bravo, EFI, MPI, TR · 88→97 BR6FS 0.9 mm
CHEVROLET HP1075 Sci Dry Sump BR9ECS 0.8 mm
CHEVROLET HP425, 450, 465 BR6FS 0.9 mm
CHEVROLET HP500 · 502 cu.inch Incl. EFI (Excl. 540 cu.inch) BR6FS 1.0 mm
CHEVROLET HP500 · 540 cu.inch R5673-8 0.9 mm
CHEVROLET HP525 (Excl. SC) · 502 cu.inch BR6ES 0.9 mm
CHEVROLET HP525 SC R5673-8 0.9 mm
CHEVROLET HP575 (Incl. SCi) R5673-8 0.9 mm
CHEVROLET HP600 SC R5673-8 0.9 mm
CHEVROLET HP600 SCi (Excl. SC) BR6ES 0.9 mm
CHEVROLET HP700 SCi BR6ES 0.9 mm
CHEVROLET HP800 SC R5673-8 0.9 mm
CHEVROLET HP850 SCi BR9ECS 0.8 mm
CHEVROLET HP900 SC (Excl. Dry Sump) R7434-9 0.7 mm
CHEVROLET HP900 SC Dry Sump R7434-9 0.6 mm
CHEVROLET L-6 165 V: 2 771 484 on BR5FS 0.9 mm
CHEVROLET L-6 165 V: To: 2 771 483 BR6ES 0.9 mm
CHEVROLET L-6 200 BR6ES 0.9 mm
DIESEL 3.0 · D3.0L · Diesel · 94→97 Y-909R
DIESEL 3.6 · D3.6L · Diesel · 94→97 Y-909R
DIESEL 3.6 · D3.6L · Diesel · 97→97 Y-909R
DIESEL 4.2 · D4.2L/220 · Diesel · 94→99 Y-909R
DIESEL 530D-TA · Diesel · 89→93 Y-909R
DIESEL 636D-TA · Diesel · 89→93 Y-909R
DIESEL D183 TURBO AC · Diesel · 90→93 Y-909R
DIESEL D219 TURBO AC · Diesel · 90→93 Y-909R
FORD 255 V: To: 4 175 498 Dia. 14 mm plug BR6FS 0.8 mm
GM 110 BR6ES 0.9 mm
GM 120 · 64→86 BR6FS 0.9 mm
GM 140 · 68→86 BR6FS 0.9 mm
GM 3.0 · 3.0L · 181 cu.inch · 82→94 BR6FS 0.9 mm
GM 3.0 · 3.0L · 181 cu.inch · 98→ BPR6EFS BPR6EFIX-10 0.9 mm
GM 3.0 · 3.0LX · 90→95 BR6FS 0.9 mm
GM 3.0 · 3.0LX · 90→97 BPR6EFS BPR6EFIX-10 0.9 mm
HP900 SC R5671A-9 0.6 mm
INBOARD 4-CYL. 470 BPR6FS 0.9 mm
INBOARD 8-CYL. FORD 233 Dia. 14 mm plug BPR6FS 0.8 mm
INBOARD 8-CYL. GM 198 BR5FS 0.9 mm
INBOARD 8-CYL. GM 325 V: To: 2 762 441 BUE 1.3 mm
MX 6.2 MPI 2006-2000 TR55 TR55IX 1.5 mm
MX 6.2 MPI 2007 IZFR7M 0.8 mm
MX 6.2 MPI HORIZON TR55 TR55IX 1.5 mm
MX 6.2 MPI HORIZON 2007 IZFR7M 0.8 mm
RENAULT 80 19 mm reach plugs BPR6ES BPR6EIX 0.6 mm
RENAULT 90 19 mm reach plugs BPR6ES BPR6EIX 0.8 mm
SCORPION 350 DTS ECT ITR4A15 1.5 mm
SCORPION 377 HO ECT BPR6EFS TR6IX 0.8 mm
SMALL BLOCK 225 B7S 0.8 mm
SMALL BLOCK 228, 230 BR5FS 0.9 mm
SMALL BLOCK 250 B7S 1.0 mm
SMALL BLOCK 255 BR6FS 0.9 mm
SMALL BLOCK 255 V: 4 175 499 on Dia. 14 mm plug BPR6FS 0.8 mm
SMALL BLOCK 255, 260 BR6FS 0.9 mm
SMALL BLOCK 270 Gasket seat plugs B7S 0.9 mm
SMALL BLOCK 270 Taper seat plugs R5673-8 0.9 mm
SMALL BLOCK 350 MAG MPI, Gen+ · 00→06 PZTR5A-15 1.5 mm
SMALL BLOCK 350 MAG MPI, Gen+ · 98→00 BPR6EFS BPR6EFIX-10 1.1 mm
SMALL BLOCK 350 MAG, EFI, MPI, SKI · 87→97 BR6FS 1.0 mm
SMALL BLOCK 454 EFI (Incl. MPI) BR6FS 1.0 mm
SMALL BLOCK 5.0 · 5.0L BR5FS 0.9 mm
SMALL BLOCK 5.0 · 5.0L MPI BR6FS 1.0 mm
SMALL BLOCK 5.7 · 5.7L Comp Gen+, EFI BPR6EFS BPR6EFIX-10 1.1 mm
SMALL BLOCK 5.7 · 5.7L, Comp BR6FS 1.0 mm
SMALL BLOCK 5.7 · Black Scorpion 5.7L · 00→06 BPR6EFS BPR6EFIX-10 1.1 mm
SMALL BLOCK 5.7 · Black Scorpion 5.7L · 00→06 PTR5D-13 TR5AI-13 1.5 mm
SMALL BLOCK 6.2 · Black Scorpion MX 6.2 · 00→06 BPR5EFS PTR5D-10 0.9 mm
SMALL BLOCK 6.2 · Black Scorpion MX 6.2 · 00→06 PTR5D-13 TR5AI-13 1.5 mm
SMALL BLOCK 6.2 · MX 6.2 MPI Horizon · 00→06 PTR5D-13 TR5AI-13 1.5 mm
SMALL BLOCK 6.2 · MX 6.2 MPI · 00→06 BPR6EFS BPR6EFIX-10 1.1 mm
SMALL BLOCK 6.2 · MX 6.2 MPI · 00→06 PTR5D-13 TR5AI-13 1.5 mm
SMALL BLOCK 888 V: 4 169 597 on Dia. 14 mm plug BPR6FS 0.8 mm
SMALL BLOCK Scorpion 377 BPR6EFS BPR6EFIX-10 1.1 mm
STERN DRIVE 4-CYL. 165, 170, 180, 190 · 224 cu.inch · 85→87 BPR6FS 0.9 mm
STERN DRIVE 4-CYL. 2.5 · 2.5L · 153 cu.inch BR6FS 0.9 mm
STERN DRIVE 4-CYL. 3.7 · 3.7L, 3.7LX · 224 cu.inch · 88→89 BPR6FS 0.9 mm
STERN DRIVE 4-CYL. 470, 485, 488 · 224 cu.inch · 76→84 BPR6FS 0.9 mm
STERN DRIVE 4-CYL. 60 12.7 mm reach plugs BR6HS BR6HIX 0.6 mm
STERN DRIVE 6-CYL. 140, 150, 160 BR6ES 0.9 mm
STERN DRIVE 6-CYL. 175, 185, 205 · 229 cu.inch · 85→87 BR6FS 0.9 mm
STERN DRIVE 6-CYL. 262 Mag EFI Gen+ BPR6EFS BPR6EFIX-10 1.1 mm
STERN DRIVE 6-CYL. 4.3 · 4.3L MPI Gen+ · 98→ PTR5D-13 TR5AI-13 1.5 mm
STERN DRIVE 6-CYL. 4.3 · 4.3L, 4.3LX · 88→96 BR6FS 1.0 mm
STERN DRIVE 6-CYL. 4.3 · 4.3L, 4.3LX, 4.3LXH, EFI, Gen+ · (Excl. MPI) · 96→98 BPR6EFS BPR6EFIX-10 1.1 mm
STERN DRIVE 8-CYL. 225 V: To: 2 278 646 B7S 0.9 mm
STERN DRIVE 8-CYL. 225, 233 Dia. 14 mm plug · 06→ BPR6FS 0.8 mm
STERN DRIVE 8-CYL. 228, 230 BR5FS 0.9 mm
STERN DRIVE 8-CYL. 250 V: 4 768 000 on BR6FS 0.9 mm
STERN DRIVE 8-CYL. 250 V: To: 2 639 854 B7S 0.8 mm
STERN DRIVE 8-CYL. 255, 260 BR6FS 0.9 mm
STERN DRIVE 8-CYL. 270 Gasket seat plugs B7S 0.8 mm
STERN DRIVE 8-CYL. 270 Taper seat plugs R5673-8 0.9 mm
STERN DRIVE 8-CYL. 280 BR6FS 0.9 mm
STERN DRIVE 8-CYL. 300 Tempest BR6FS 0.9 mm
STERN DRIVE 8-CYL. 320 EFI BR6FS 0.9 mm
STERN DRIVE 8-CYL. 325 V: To: 2 761 141 BUE 1.3 mm
STERN DRIVE 8-CYL. 350 Mag EFI, MPI Gen+, Horizon BPR6EFS BPR6EFIX-10 1.1 mm
STERN DRIVE 8-CYL. 350 Mag EFI, MPI V: To: 0F 602 199 BR6FS 1.0 mm
STERN DRIVE 8-CYL. 350 Mag MPI Gen+ Horizon BPR5EFS PTR5D-10 0.9 mm
STERN DRIVE 8-CYL. 350 Mag MPI Gen+ Horizon PTR5D-13 TR5AI-13 1.5 mm
STERN DRIVE 8-CYL. 400, 420, 440, Incl. Cyclone BR6FS 0.9 mm
STERN DRIVE 8-CYL. 5.0 · 5.0L MPI · 02→ PTR5D-13 TR5AI-13 1.5 mm
STERN DRIVE 8-CYL. 5.0 · 5.0L, 5.0LX · 88→95 BR6FS 0.9 mm
STERN DRIVE 8-CYL. 5.0 · 5.0L, EFI, Gen+ · 98→01 BPR6EFS BPR6EFIX-10 1.1 mm
STERN DRIVE 8-CYL. 5.7 · 5.7L, 5.7LX (Incl. EFI) · 88→97 BR6FS 1.0 mm
STERN DRIVE 8-CYL. 5.7 · 5.7L, 5.7LX, Gen+ (Incl. EFI) · 98→01 BPR6EFS BPR6EFIX-10 1.1 mm
STERN DRIVE 8-CYL. 6.2 · MX 6.2 MPI V: To: 0M 320 613 BPR6EFS BPR6EFIX-10 1.1 mm
STERN DRIVE 8-CYL. 6.2 · MX 6.2 MPI, Horizon V: 0M 320 614 on PTR5D-13 TR5AI-13 1.5 mm
STERN DRIVE 8-CYL. 898, 200 BR5FS 0.9 mm
STERN DRIVE 8-CYL. Scorpion 377 V: 0L 416 146 on BPR6EFS BPR6EFIX-10 1.1 mm

Chrysler 49 applications

Model Engine / details NGK plug Premium upgrade Gap
6-CYL. M225D · 28 hp · →74 BR6ES 0.9 mm
6-CYL. M225D · 30 hp · 75→79 BPR6FS 0.9 mm
6-CYL. M225D · 35 hp BR6ES 0.9 mm
4-CYL. M122A, M122B B7HS BR7HIX 0.9 mm
4-CYL. M91D, M91F BP6ES BPR6EIX 0.9 mm
6-CYL. B46-4, B46S-3 BR6S 0.9 mm
6-CYL. M170 BR6ES 0.9 mm
6-CYL. M183B B7HS BR7HIX 0.9 mm
6-CYL. M225A BR6ES 0.9 mm
6-CYL. M225GD BR6ES 0.9 mm
6-CYL. M265, M265A BR6S 0.9 mm
6-CYL. M46-3 BR6S 0.9 mm
6-CYL. M47-3, M47-4, M47S-3 BR6S 0.9 mm
8-CYL. LM318A, LM318AC BPR6ES BPR6EIX 0.9 mm
8-CYL. LM318B, LM318BC, LM318BJ, BPR6ES BPR6EIX 0.9 mm
8-CYL. LM318D BPR6ES BPR6EIX 0.9 mm
8-CYL. LM340B, LM340BJ, LM340BT, LM340BV BPR6ES BPR6EIX 0.9 mm
8-CYL. M273A, M273B, M273BT BPR6ES BPR6EIX 0.9 mm
8-CYL. M360A, M360B, M360BC, M360BJ, BPR6ES BPR6EIX 0.9 mm
8-CYL. M413E BR6ES 0.9 mm
8-CYL. M44, M44-3 BR6S 0.9 mm
8-CYL. M45, M45-3 BR6ES 0.9 mm
8-CYL. M45S, M45-S3, M45-SP3 BR6ES 0.9 mm
8-CYL. M460B BPR5FS 0.9 mm
8-CYL. M81 BR6ES 0.9 mm
M318A XR5 XR5IX 0.9 mm
M318B XR5 XR5IX 0.9 mm
M318C XR5 XR5IX 0.9 mm
M318GD XR5 XR5IX 0.9 mm
M383B XR5 XR5IX 0.9 mm
M383BV XR5 XR5IX 0.9 mm
M400B XR5 XR5IX 0.9 mm
M400BV XR5 XR5IX 0.9 mm
M400S XR5 XR5IX 0.9 mm
M413B XR5 XR5IX 0.9 mm
M413D XR5 XR5IX 0.9 mm
M426-SKI XR5 XR5IX 0.9 mm
M426B XR5 XR5IX 0.9 mm
M426D XR5 XR5IX 0.9 mm
M440B XR5 XR5IX 0.9 mm
M440BJ XR5 XR5IX 0.9 mm
M440BV XR5 XR5IX 0.9 mm
M440D XR5 XR5IX 0.9 mm
M440S XR5 XR5IX 0.9 mm
M440SV XR5 XR5IX 0.9 mm
M460B UR5 UR5IX 0.9 mm
M80 XR5 XR5IX 0.9 mm
M91D BPR6EY BPR6EIX 0.9 mm
M91F BPR6EY BPR6EIX 0.9 mm

Mercury 12 applications

Model Engine / details NGK plug Premium upgrade Gap
90 HP Sport Jet · 94→ BZ7HS-10 1.0 mm
95 HP Sportjet 95XR · 96→97 BZ7HS-10 1.0 mm
120 HP Sportjet 120 (Excl. XR) · 95→ BZ7HS-10 1.0 mm
120 HP Sportjet 120XR · 96→99 BZ7HS-10 0.8 mm
175 HP Sportjet 175XR · 97→06 BUZ8H 1.5 mm
200 HP Sport Jet · 06→ IZFR5G 0.8 mm
210 HP M2 Sport Jet · 00→06 BUZ8H 1.5 mm
240 HP M2 Sport Jet · 00→06 BPZ8HS-10 1.0 mm
250 HP M2 Sport Jet · 06→ IZFR5G 0.8 mm
M2 SPORT JET 2006 IZFR5G 0.8 mm
SPORT JET 1994 BZ7HS-10 0.9 mm
SPORT JET 2006 IZFR5G 0.8 mm

Chevrolet (marine conversions) 13 applications

Model Engine / details NGK plug Premium upgrade Gap
6-CYL. 194 cu.inch · 62→69 BPR5ES BPR5EIX 0.9 mm
6-CYL. 230 cu.inch · 62→69 BPR5ES BPR5EIX 0.9 mm
6-CYL. 230 cu.inch · 70→ BPR4FS-11 1.1 mm
6-CYL. 250 cu.inch · 62→69 BPR5ES BPR5EIX 0.9 mm
6-CYL. 250 cu.inch · 79→84 BPR4FS-11 1.1 mm
6-CYL. 292 cu.inch · 63→69 BPR4FS-11 1.1 mm
6-CYL. 292 cu.inch · 70→78 BPR5FS 0.7 mm
8-CYL. 307 cu.inch · 71→73 BPR5FS 0.7 mm
8-CYL. 350 cu.inch · 71→90 BPR4FS-11 1.1 mm
8-CYL. 400 cu.inch · 71→90 BPR4FS-11 1.1 mm
8-CYL. 427 cu.inch · 71→72 BPR6FS 0.7 mm
8-CYL. 427 cu.inch · 73→90 BPR4FS-11 1.1 mm
8-CYL. 454 cu.inch · 79→90 BPR5FS 0.8 mm

Ford 10 applications

Model Engine / details NGK plug Premium upgrade Gap
104 cu.inch BPR4ES GR4IX 0.7 mm
158 cu.inch BR6ES 0.9 mm
172 cu.inch B-6L 0.7 mm
201 cu.inch BR6ES 0.9 mm
427 cu.inch 302, 351W Dia. 18 mm plug · →74 APR5FS 0.9 mm
427 cu.inch Dia. 14 mm plug · 75→89 BPR5FS 0.7 mm
429 cu.inch 75→89 BPR5FS 0.7 mm
460 cu.inch 302, 351W Dia. 14 mm plug · 75→89 BPR5FS 0.8 mm
67 cu.inch BPR5E BPR5EIX 0.9 mm
98 cu.inch BPR5E BPR5EIX 0.9 mm

Toyota 7 applications

Model Engine / details NGK plug Premium upgrade Gap
EPIC 21, 22 IFR6T11 1.1 mm
EPIC 4.0 · VT 300i · 8-Cyl. PFR5G-11 BKR5EIX-11 1.1 mm
EPIC 21 - 4.0L IFR6T11 1.1 mm
EPIC 22 - 4.0L IFR6T11 1.1 mm
S22 - 4.0L IFR6T11 1.1 mm
S22, X22 S22, X22 IFR6T11 1.1 mm
X22 - 4.0L IFR6T11 1.1 mm

Reading the plug codes

An NGK code describes the plug's construction. The digit in the middle is the heat rating — a higher number is a colder plug, which is the opposite of most other brands. An R after the first letters means a resistor plug. Codes ending IX are the Iridium IX range and G or GP the platinum ranges, both direct upgrades with a finer centre electrode. A Y- prefix is a diesel glow plug, not a spark plug, and has no gap.

Do not substitute a hotter or colder plug to cure a running problem. A plug reading the wrong colour is telling you about the fuel, ignition or oil — changing heat range hides it rather than fixing it.

Other engines

Not sure which plug you need?

Model families ran across several specifications and the year or serial usually decides which line applies. Ring 0412 532 984 with your engine and serial number and we will confirm the plug, the gap and how many you need. Our other workshop charts are on the reference charts page.

Applications compiled from NGK's published marine application guide and the NGK non-automotive catalogue, and reproduced here as reference data. NGK's own guides are the authority; always confirm against your engine's manual. Listings do not apply to racing or modified engines.