# NGK Spark Plugs: Mercury Outboards ## NGK Spark Plugs: Mercury Outboards 203 spark plug applications from NGK's marine catalogue, for the engines we supply parts for. Each line gives the plug NGK specifies, the iridium upgrade where one exists, and the electrode gap. **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. - [Mercury](#mercury) ### Mercury 203 applications Model Engine / details NGK plug Iridium upgrade Gap 2.2 HP 2.2 · 84→89 BPR6HS-10 BPR6HIX 1.0 mm 2.5 HP 2.5 · 93→05 BPR6HS BPR6HIX 0.8 mm 2.5 HP 2.5 · 06→ BPR6HS-10 BPR6HIX 1.0 mm 3 HP 3 · 90→92 BPR6HS-10 BPR6HIX 1.0 mm 3.3 HP 3.3 · 93→06 BPR6HS-10 BPR6HIX 1.0 mm 3.5 HP 3.5 · 83→85 BP6HS-10 BPR6HIX 1.0 mm 3.6 HP 3.6 · 80→82 BP7HS-10 BPR7HIX 1.0 mm 3.9 HP 3.9 · 64→66 B6S 0.6 mm 3.9 HP 3.9 · 67→68 B5HS 0.8 mm 4 HP 4 · 80→82 BP7HS BPR7HIX 0.9 mm 4 HP 4 · Dia. 14 mm plug · 2-Stroke · 88→06 BPR7HS-10 BPR7HIX 1.0 mm 4 HP 4 · Dia. 12 mm plug · 4-Stroke · 00→06 DCPR6E 0.9 mm 4 HP 4 · 40 · 69→69 B5HS 0.8 mm 4 HP 4 · 40 Gnat · 76→79 BR6HS BR6HIX 0.8 mm 5 HP 5 · Dia. 14 mm plug · 2-Stroke · 88→06 BPR7HS-10 BPR7HIX 1.0 mm 5 HP 5 · Dia. 12 mm plug · 4-Stroke · 00→06 DCPR6E 0.9 mm 6 HP 6 · 60 9.5 mm reach plugs · 63→66 B6S 0.6 mm 6 HP 6 · 60 12.7 mm reach plugs · 67→68 B6HS BR6HIX 0.8 mm 6 HP 6 · Dia. 14 mm plug · 2-Stroke · 86→00 BP8H-N-10 BPR8HIX 1.0 mm 6 HP 6 · Dia. 14 mm plug · 2-Stroke · 01→06 BPZ8H-N-10 1.0 mm 6 HP 6 · Dia. 12 mm plug · 4-Stroke · 00→06 DCPR6E 0.9 mm 7.5 HP 7.5 · →69 B6HS BR6HIX 0.8 mm 7.5 HP 7.5 · 79→85 B9HS-10 BR9HIX 1.0 mm 8 HP 8 · Dia. 14 mm plug · 2-Stroke · 86→00 BP8H-N-10 BPR8HIX 1.0 mm 8 HP 8 · Dia. 14 mm plug · 2-Stroke · 01→06 BPZ8H-N-10 1.0 mm 8 HP 8 · Dia. 12 mm plug · 4-Stroke · 06→ DCPR6E 0.9 mm 8 HP 8 · Bodensee Dia. 10 mm plug · 95→02 CR6HS CR6HIX 0.7 mm 9.8 HP 9.8 · 100, 110 9.5 mm reach plugs · 60→66 B6S 0.6 mm 9.8 HP 9.8 · 110 12.7 mm reach plugs · 67→69 B7HS BR7HIX 0.8 mm 9.8 HP 9.8 · 79→85 B9HS-10 BR9HIX 1.0 mm 9.9 HP 9.9 · 2-Stroke · 86→94 BP8H-N-10 BPR8HIX 1.0 mm 9.9 HP 9.9 · 2-Stroke · 95→00 BP8HS-15 1.5 mm 9.9 HP 9.9 · 2-Stroke · 01→06 BPZ8HS-15 1.5 mm 9.9 HP 9.9 · 4-Stroke · 95→98 CR6HS CR6HIX 0.7 mm 9.9 HP 9.9 · 4-Stroke · 99→02 DPR6EA-9 0.9 mm 9.9 HP 9.9 · 4-Stroke · 06→ DCPR6E 0.9 mm 10 HP 10 · 10, 10M Sea Pro · (Excl. RFI) · 91→00 BP8HS-15 1.5 mm 10 HP 10 · 10 Sea Pro · 01→02 BPZ8HS-15 1.5 mm 10 HP 10 · 10M, 10ML Sea Pro · RFI BPR7HS-10 BPR7HIX 1.0 mm 10 HP 10 · 10ML Sea Pro · (Excl. RFI) · 91→00 BP8HS-15 1.5 mm 10 HP 10 · XR10 · 92→98 BP8HS-15 1.5 mm 15 HP 15 · 15M, 15ML · RFI · 95→96 BP8HS-10 BPR8HIX 1.0 mm 15 HP 15 · 150 · 60→61 B6S 0.6 mm 15 HP 15 · Bigfoot · 4-Stroke · 98→06 DPR6EA-9 0.9 mm 15 HP 15 · Sea Pro · 2-Stroke · 95→96 BP8HS-10 BPR8HIX 1.0 mm 15 HP 15 · Sea Pro · 2-Stroke · 97→00 BP8HS-15 1.5 mm 15 HP 15 · Sea Pro · 2-Stroke · 01→06 BPZ8HS-15 1.5 mm 18 HP 18 · 18 XD · 81→85 BP8H-N-10 BPR8HIX 1.0 mm 20 HP 20 · 200 · 60→66 B6S 0.6 mm 20 HP 20 · 200 · 67→69 B7HS BR7HIX 0.8 mm 20 HP 20 · 2-Stroke · 86→00 BP8H-N-10 BPR8HIX 1.0 mm 20 HP 20 · 2-Stroke · 01→06 BPZ8H-N-10 1.0 mm 20 HP 20 · Jet · 2-Stroke · 95→00 BP8H-N-10 BPR8HIX 1.0 mm 20 HP 20 · Jet · 2-Stroke · 01→02 BPZ8H-N-10 1.0 mm 20 HP 20 · Sea Pro · 2-Stroke · 01→ BPZ8H-N-10 1.0 mm 25 HP 25 · 25M, 25ML · (Excl. RFI) BP7HS-10 BPR7HIX 1.0 mm 25 HP 25 · 25M, 25ML · RFI BPR7HS-10 BPR7HIX 1.0 mm 25 HP 25 · 25MLRC · 2-Stroke · 98→08 BPZ8H-N-10 1.0 mm 25 HP 25 · 250 · 62→ B6S 0.6 mm 25 HP 25 · Sea Pro · 2-Stroke · 80→00 BP8H-N-10 BPR8HIX 1.0 mm 25 HP 25 · Bigfoot · 4-Stroke · 98→01 DPR6EA-9 0.9 mm 25 HP 25 · 4-Stroke EFI · 06→ DCPR6E 0.9 mm 30 HP 30 · 300 · 4-Cyl. · 60→ B6S 0.6 mm 30 HP 30 · Incl. Sea Pro · 2-Stroke 2-Cyl. · 95→00 BP8H-N-10 BPR8HIX 1.0 mm 30 HP 30 · Incl. Jet, Sea Pro · 2-Stroke 2-Cyl. · 01→ BPZ8H-N-10 1.0 mm 30 HP 30 · Jet · 2-Stroke 3-Cyl. · 98→01 BP8H-N-10 BPR8HIX 1.0 mm 30 HP 30 · 2-Stroke 3-Cyl. · 01→ BPZ8H-N-10 1.0 mm 30 HP 30 · 4-Stroke 2-Cyl. · 99→02 DPR6EA-9 0.9 mm 30 HP 30 · 4-Stroke 3-Cyl. EFI · 06→ DCPR7E DCPR7EIX 0.9 mm 35 HP 35 · 350 9.5 mm reach plugs · 4-Cyl. · 61→65 B6S 0.6 mm 35 HP 35 · 350 9.5 mm reach plugs · 66→66 B7S 0.6 mm 35 HP 35 · 350 12.7 mm reach plugs · 67→69 B7HS BR7HIX 0.8 mm 40 HP 40 · 40ML, 40MLL · (Excl. RFI) BP7HS-10 BPR7HIX 1.0 mm 40 HP 40 · 40ML, 40MLL · RFI BPR7HS-10 BPR7HIX 1.0 mm 40 HP 40 · 400 · 60→61 B6S 0.6 mm 40 HP 40 · Incl. Sea Pro · 2-Stroke 2-Cyl. · 95→00 BP8H-N-10 BPR8HIX 1.0 mm 40 HP 40 · Incl. Sea Pro · 2-Stroke 2-Cyl. · 01→06 BPZ8H-N-10 1.0 mm 40 HP 40 · Sea Pro · 2-Stroke 3-Cyl. · 95→97 BPR7HS-10 BPR7HIX 1.0 mm 40 HP 40 · 2-Stroke 3-Cyl. · 98→00 BP8H-N-10 BPR8HIX 1.0 mm 40 HP 40 · 2-Stroke 3-Cyl. · 01→02 BPZ8H-N-10 1.0 mm 40 HP 40 · Bigfoot · 4-Stroke 3-Cyl. · 98→02 DPR6EA-9 0.9 mm 40 HP 40 · 4-Stroke 3-Cyl. EFI · 06→ DCPR7E DCPR7EIX 0.9 mm 40 HP 40 · Bigfoot · 4-Stroke 4-Cyl. (Excl. EFI) · 01→06 DPR6EA-9 0.9 mm 40 HP 40 · 4-Stroke 4-Cyl. EFI · 06→ DCPR7E DCPR7EIX 0.9 mm 45 HP 45 · 450 · 62→ B6S 0.6 mm 45 HP 45 · Bodensee Dia. 12 mm plug · 4-Cyl. 4-Stroke · 95→02 DPR6EA-9 0.9 mm 45 HP 45 · Jet Dia. 14 mm plug · 3-Cyl. 2-Stroke · 95→00 BP8H-N-10 BPR8HIX 1.0 mm 45 HP 45 · Jet Dia. 14 mm plug · 3-Cyl. 2-Stroke · 01→02 BPZ8H-N-10 1.0 mm 50 HP 50 · 500 9.5 mm reach plugs · 61→64 B6S 0.6 mm 50 HP 50 · 500 9.5 mm reach plugs · 65→66 B7S 0.6 mm 50 HP 50 · 500M, 500S (Excl. 500SS) · 67→77 B7HS BR7HIX 0.8 mm 50 HP 50 · 3-Cyl. 2-Stroke · 91→00 BP8H-N-10 BPR8HIX 1.0 mm 50 HP 50 · 3-Cyl. 2-Stroke · 01→06 BPZ8H-N-10 1.0 mm 50 HP 50 · (Excl. Big Foot) · 4-Cyl. 4-Stroke · 95→01 DPR6EA-9 0.9 mm 50 HP 50 · 4-Cyl. 4-Stroke EFI · 06→ DCPR7E DCPR7EIX 0.9 mm 50 HP 50 · Big Foot · 4-Stroke · 95→ DCPR7E DCPR7EIX 0.9 mm 55 HP 55 · ML, MLL Sea Pro · (Excl. RFI) BP7HS-10 BPR7HIX 1.0 mm 55 HP 55 · ML, MLL Sea Pro · RFI BPR7HS-10 BPR7HIX 1.0 mm 55 HP 55 · Sea Pro · 3-Cyl. 2-Stroke · 92→00 BP8H-N-10 BPR8HIX 1.0 mm 55 HP 55 · Sea Pro · 3-Cyl. 2-Stroke · 01→06 BPZ8H-N-10 1.0 mm 60 HP 60 · 6-Cyl. · 60→ B6S 0.6 mm 60 HP 60 · 3-Cyl. 2-Stroke · 91→00 BP8H-N-10 BPR8HIX 1.0 mm 60 HP 60 · 3-Cyl. 2-Stroke · 01→06 BPZ8H-N-10 1.0 mm 60 HP 60 · 4-Cyl. 4-Stroke · 01→ DPR6EA-9 0.9 mm 60 HP 60 · 4-Cyl. 4-Stroke EFI · 06→ DCPR7E DCPR7EIX 0.9 mm 60 HP 60 · Big Foot · 95→02 BP8H-N-10 BPR8HIX 1.0 mm 60 HP 60 · ML, MLL Sea Pro · (Excl. RFI) BP7HS-10 BPR7HIX 1.0 mm 60 HP 60 · ML, MLL Sea Pro · RFI BPR7HS-10 BPR7HIX 1.0 mm 60 HP 60 · Sea Pro · 3-Cyl. 2-Stroke · 95→00 BP8H-N-10 BPR8HIX 1.0 mm 60 HP 60 · Sea Pro · 3-Cyl. 2-Stroke · 01→02 BPZ8H-N-10 1.0 mm 65 HP 65 · 650 9.5 mm reach plugs · 63→66 B7S 0.6 mm 65 HP 65 · 650S (Excl. 650SS) · 67→67 B7HS BR7HIX 0.8 mm 65 HP 65 · 650SS · 67→71 BUH 70 HP 70 · 700 · 60→61 B6S 0.6 mm 75 HP 75 · 4-Cyl. 4-Stroke DOHC · 00→06 LFR5AP-11 1.1 mm 80 HP 80 · 800 · 6-Cyl. · 60→61 B7S 0.6 mm 80 HP 80 · 800 · 66→68 BU8H 80 HP 80 · Jet · 4-Cyl. 2-Stroke · 95→00 BP8H-N-10 BPR8HIX 1.0 mm 80 HP 80 · Jet · 4-Cyl. 2-Stroke · 01→ BPZ8H-N-10 1.0 mm 85 HP 85 · 850 · 6-Cyl. · 62→64 B7S 0.6 mm 90 HP 90 · 900 9.5 mm reach plugs · 65→77 B7S 0.6 mm 90 HP 90 · 4-Cyl. 4-Stroke DOHC · 00→06 LFR5AP-11 1.1 mm 95 HP 95 · 950 (Excl. 950SS) · 66→ B7HS BR7HIX 0.8 mm 100 HP 100 · 1000 · 62→64 B7S 0.6 mm 100 HP 100 · 88→99 BP8H-N-10 BPR8HIX 1.0 mm 105 HP 105 · Jet · 95→98 BU8H 110 HP 110 · 1100BP (Excl. 1100SS) · 66→ B7HS BR7HIX 0.8 mm 115 HP 115 · 4-Cyl. 2-Stroke · 89→00 BP8H-N-10 BPR8HIX 1.0 mm 115 HP 115 · 4-Cyl. 2-Stroke · 01→06 BPZ8H-N-10 1.0 mm 115 HP 115 · 4-Cyl. 4-Stroke EFI, MFI · 01→06 ILFR6J-11K 1.1 mm 115 HP 115 · OptiMax · 6-Cyl. 2-Stroke · 00→02 PZFR5F-11 ZFR5FIX-11 1.0 mm 115 HP 115 · OptiMax · 6-Cyl. 2-Stroke · 03→04 IZFR5G 0.8 mm 125 HP 125 · 4-Cyl. 2-Stroke · 94→00 BP8H-N-10 BPR8HIX 1.0 mm 125 HP 125 · 4-Cyl. 2-Stroke · 01→06 BPZ8H-N-10 1.0 mm 135 HP 135 · 86→99 BU8H 135 HP 135 · 6-Cyl. 4-Stroke EFI Supercharged · 06→ ILFR6B 0.8 mm 135 HP 135 · OptiMax · 6-Cyl. 2-Stroke DFI · 96→01 PZFR5F-11 ZFR5FIX-11 1.0 mm 135 HP 135 · OptiMax · 6-Cyl. 2-Stroke DFI · 03→06 IZFR5G 0.8 mm 140 HP 140 · Jet · 95→99 BU8H 150 HP 150 · 1500 · V6 · 78→97 BU8H 150 HP 150 · EFI · 98→99 BU8H 150 HP 150 · 6-Cyl. 2-Stroke EFI · 00→06 BPZ8HS-10 1.0 mm 150 HP 150 · 6-Cyl. 4-Stroke EFI Supercharged · 06→ ILFR6B 0.8 mm 150 HP 150 · Marathon · 85→88 BU8H 150 HP 150 · OptiMax · 6-Cyl. 2-Stroke DFI · 96→02 PZFR5F-11 ZFR5FIX-11 1.0 mm 150 HP 150 · OptiMax · 6-Cyl. 2-Stroke DFI · 03→06 IZFR5G 0.8 mm 150 HP 150 · XR-2, XR-4, XR-6, XRi · V6 · 85→02 BU8H 175 HP 175 · V6, EFI · 79→99 BU8H 175 HP 175 · 6-Cyl. 2-Stroke EFI, MFI · 00→01 BPZ8HS-10 1.0 mm 175 HP 175 · 6-Cyl. 4-Stroke EFI Supercharged · 06→ ILFR6B 0.8 mm 175 HP 175 · OptiMax · 6-Cyl. 2-Stroke DFI · 01→02 PZFR5F-11 ZFR5FIX-11 1.0 mm 175 HP 175 · OptiMax · 6-Cyl. 2-Stroke DFI · 03→06 IZFR5G 0.8 mm 175 HP 175 · XRi · 91→02 BU8H 200 HP 200 · V6 · 79→99 BU8H 200 HP 200 · 6-Cyl. 2-Stroke, Incl. EFI, MFI · 00→06 BPZ8HS-10 1.0 mm 200 HP 200 · 6-Cyl. 2-Stroke EFI · 06→ BR8HS BR8HIX 1.0 mm 200 HP 200 · DFI V6 · 96→97 ZFR6F-11 ZFR6FIX-11 1.1 mm 200 HP 200 · DFI · 97→ PZFR6H 1.0 mm 200 HP 200 · EFI · 98→99 BU8H 200 HP 200 · 26.5 mm reach plugs · EFI · 06→ ILFR6B 0.8 mm 200 HP 200 · Deuce High · EFI · 97→ BUZ8H 200 HP 200 · OptiMax · 6-Cyl. 2-Stroke · 96→02 PZFR5F-11 ZFR5FIX-11 1.0 mm 200 HP 200 · OptiMax · 6-Cyl. 2-Stroke · 03→06 IZFR5G 0.8 mm 200 HP 200 · OptiMax 200XS · 00→04 PZFR5F-11 ZFR5FIX-11 1.0 mm 200 HP 200 · OptiMax 200XS · 00→04 PZFR5F-11 ZFR5FIX-11 1.0 mm 200 HP 200 · Verado · 6-Cyl. 4-Stroke · 04→ ILFR6B 0.8 mm 200 HP 200 · XRi · V6 · 89→02 BUZ8H 200 HP 200 · XRi · EFI V6 · 00→ BPR7HS BPR7HIX 0.8 mm 220 HP 220 · V-220 Laser · 87→88 BUZ8H 225 HP 225 · 80→81 BU8H 225 HP 225 · DFI · 97→ PZFR5F-11 ZFR5FIX-11 1.0 mm 225 HP 225 · 6-Cyl. 2-Stroke EFI, DFI · 95→06 BR8HS BR8HIX 0.9 mm 225 HP 225 · V6 · 94→97 BPZ8H-N-10 1.0 mm 225 HP 225 · V6 2-Stroke · 98→01 BR8HS BR8HIX 0.9 mm 225 HP 225 · 6-Cyl. 4-Stroke EFI, DFI (Excl. · 06→ LFR5AP-11 1.1 mm 225 HP 225 · 6-Cyl. 4-Stroke EFI Supercharged · 06→ ILFR6B 0.8 mm 225 HP 225 · OptiMax (Excl. 225XS) · 6-Cyl. 2-Stroke · 96→04 PZFR5F-11 ZFR5FIX-11 1.0 mm 225 HP 225 · OptiMax · 6-Cyl. 2-Stroke · 06→ IZFR5G 0.8 mm 225 HP 225 · Sea Pro · V6 · 95→97 BPR7HS-10 BPR7HIX 1.0 mm 225 HP 225 · Sea Pro · 6-Cyl. 2-Stroke · 97→02 BR8HS BR8HIX 0.9 mm 225 HP 225 · Verado · 6-Cyl. 4-Stroke · 04→ ILFR6B 0.8 mm 225 HP 225 · Work · 94→97 BPZ8H-N-10 1.0 mm 225 HP 225 · Work · 98→ BR8HS BR8HIX 0.9 mm 225 HP 225 · XRi · EFI · 95→02 BR8HS BR8HIX 0.9 mm 245 HP 245 · 95→96 BU8H 250 HP 250 · 89→90 BU8H 250 HP 250 · 6-Cyl. 4-Stroke EFI Supercharged · 06→ ILFR6B 0.8 mm 250 HP 250 · Verado · 6-Cyl. 4-Stroke · 04→ ILFR6B 0.8 mm 250 HP 250 · XRi · V6 EFI 2-Stroke · 95→06 BR8HS BR8HIX 0.9 mm 260 HP 260 · Offshore · 95→97 BU8H 265 HP 265 · SS Drag · EFI · 97→ BU8H 275 HP 275 · 84→94 BU8H 275 HP 275 · 6-Cyl. 4-Stroke EFI Supercharged · 06→ ILFR6B 0.8 mm 275 HP 275 · Verado · 6-Cyl. 4-Stroke · 04→ ILFR6B 0.8 mm 280 HP 280 · F1 · EFI · 97→ BU8H 280 HP 280 · Offshore · 02→ BZ7HS-10 0.8 mm 280 HP 280 · Sport, SS · EFI · 02→ BZ7HS-10 0.8 mm 300 HP 300 · 81→83 BU8H 300 HP 300 · 84→88 BU8H 300 HP 300 · S3000 · EFI · 97→ BU8H 350 HP 350 · Verado · 09→ ILFR6B 0.8 mm All models 10X BP8HS-10 BPR8HIX 1.0 mm All models Drag, S3000 · Incl. RFI 2507cc BU8H Parts for these engines: [Mercury parts](/collections/quicksilver-marine-parts-oils-service-kits-engine-components). ### 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, a direct upgrade 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 - [Mariner / Force](/pages/ngk-spark-plugs-mariner-force-outboards) - [Yamaha](/pages/ngk-spark-plugs-yamaha-outboards) - [Suzuki](/pages/ngk-spark-plugs-suzuki-outboards) - [Johnson](/pages/ngk-spark-plugs-johnson-outboards) - [Evinrude / OMC](/pages/ngk-spark-plugs-evinrude-omc-outboards) - [Tohatsu / Nissan](/pages/ngk-spark-plugs-tohatsu-nissan-outboards) - [Honda / Volvo Penta / others](/pages/ngk-spark-plugs-honda-volvo-penta-outboards) - [MerCruiser inboard](/pages/ngk-spark-plugs-mercruiser-inboard) - [Other inboards](/pages/ngk-spark-plugs-inboard-sterndrive) - [PWC & jet ski](/pages/ngk-spark-plugs-pwc-jet-ski) ### 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](tel:+61412532984) 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](/pages/resources), and the how-and-why lives in our [boat maintenance guides](/blogs/guides). Applications compiled from NGK's published marine application guide and reproduced here as reference data. NGK's own guide is the authority; always confirm against your engine's manual. Listings do not apply to racing or modified engines. --- > Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/pages/ngk-spark-plugs-mercury-outboards)