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Small Engine Spark Plug - How it Works & Installation Tips

This video provides general information on small engine spark plugs and general installation guidelines.

Small Engine

316.29937

316.77238

316.772380

41AR4BPG966

BC5090

CC5090

MP426CS

TB525CS

TB575SS

String trimmer won't start

Inspect the spark plug for signs of wear or damage. If the porcelain insulator is cracked, an electrode is burned away or damaged, or there is heavy carbon buildup at the electrode, replace the spark plug. To determine if the spark plug is defective, use a spark plug tester. You should see a strong spark between the tester’s terminals when the engine is cranking. If there is no spark, this indicates that the spark plug is defective and should be replaced.

String trimmer runs rough

Edger won't start

The spark plug ignites the fuel and air mixture in the engine's cylinder to power the engine. If the spark plug is defective, the engine may not start. To determine if the spark plug is defective, remove the spark plug and inspect it. If the porcelain insulator is cracked, an electrode has been burned away or damaged, or there is heavy carbon buildup at the electrode, replace the spark plug. Alternatively, if the spark plug hasn’t been replaced in a few seasons, replace it.

Leaf blower won't start

Leaf blower running rough

Edger runs rough

The spark plug ignites the fuel and air mixture in the engine's cylinder to power the engine. If the spark plug is defective, the engine may run roughly. To determine if the spark plug is defective, remove the spark plug and inspect it. If the porcelain insulator is cracked, an electrode has been burned away or damaged, or there is heavy carbon buildup at the electrode, replace the spark plug. Alternatively, if the spark plug hasn’t been replaced in a few seasons, replace it.

Small engine hard to start

Small engine runs poorly

Small engine won't start

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Spark Plug

Tiller engine won't start? This video provides information on how to troubleshoot a tiller and the most likely defective parts associated with this problem. Commonly replaced tiller parts: Starter Assembly Pull Rope Gas Tank Fuel Line Carburetor Fuel Filter Air Filter Chain Tine Spark Plug The information provided in this tiller troubleshooting video is applicable to all tiller brands: Ariens, Bolens, Craftsman, Cub Cadet, Dixon, Echo, Exmark, Green Machine, Homelite, Honda, Huskee, Husqvarna, John Deere, Lawn Boy, MasterCut, Montgomery Wards, MTD, Murray, Poulan, Poulan Pro, Ryobi, Simplicity, Toro, Snapper, Troy-Bilt, Turf King, Weed Eater, Wheel Horse, Worx, Yard Machines, Yard-Man

Top Reasons Tiller Engine Won't Start  — Tiller Troubleshooting

String trimmer won't start? This video provides information on how to troubleshoot a string trimmer that won't start and the most likely defective parts associated with this problem. Commonly replaced string trimmer parts: Air Filter Spark Plug Carburetor Start Pulley Pull Rope Starter Gas Tank Fuel Line The information provided in this string trimmer troubleshooting video is applicable to all string trimmer brands: Ariens, Bolens, Craftsman, Cub Cadet, Dixon, Echo, Exmark, Green Machine, Homelite, Honda, Huskee, Husqvarna, John Deere, Lawn Boy, MasterCut, Montgomery Wards, MTD, Murray, Poulan, Poulan Pro, Ryobi, Simplicity, Toro, Snapper, Troy-Bilt, Turf King, Weed Eater, Wheel Horse, Worx, Yard Machines, Yard-Man

Top Reasons String Trimmer Not Starting — String Trimmer Troubleshooting

Leaf blower won't start? This video provides information on how to troubleshoot a leaf blower and the most likely defective parts associated with this problem. Commonly replaced leaf blower parts: Starter Assembly Pull Rope Gas Tank Fuel Line Carburetor Fuel Filter Air Filter The information provided in this leaf blower troubleshooting video is applicable to all leaf blower brands: Ariens, Bolens, Craftsman, Cub Cadet, Dixon, Echo, Exmark, Green Machine, Homelite, Honda, Huskee, Husqvarna, John Deere, Lawn Boy, MasterCut, Montgomery Wards, MTD, Murray, Poulan, Poulan Pro, Ryobi, Simplicity, Toro, Snapper, Troy-Bilt, Turf King, Weed Eater, Wheel Horse, Worx, Yard Machines, Yard-Man

Top Reasons Leaf Blower Won't Start — Leaf Blower Troubleshooting

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Top Reasons Edger Won't Start — Edger Troubleshooting

Tiller engine hard to start? This video provides information on how to troubleshoot a tiller and the most likely defective parts associated with this problem. Commonly replaced tiller parts: Starter Assembly Pull Rope Gas Tank Fuel Line Carburetor Fuel Filter Air Filter Chain Tine Spark Plug The information provided in this tiller troubleshooting video is applicable to all tiller brands: Ariens, Bolens, Craftsman, Cub Cadet, Dixon, Echo, Exmark, Green Machine, Homelite, Honda, Huskee, Husqvarna, John Deere, Lawn Boy, MasterCut, Montgomery Wards, MTD, Murray, Poulan, Poulan Pro, Ryobi, Simplicity, Toro, Snapper, Troy-Bilt, Turf King, Weed Eater, Wheel Horse, Worx, Yard Machines, Yard-Man

Top Reasons Tiller Engine Hard To Start  — Tiller Troubleshooting

Tiller engine runs poorly? This video provides information on how to troubleshoot a tiller and the most likely defective parts associated with this problem. Commonly replaced tiller parts: Starter Assembly Pull Rope Gas Tank Fuel Line Carburetor Fuel Filter Air Filter Chain Tine Spark Plug The information provided in this tiller troubleshooting video is applicable to all tiller brands: Ariens, Bolens, Craftsman, Cub Cadet, Dixon, Echo, Exmark, Green Machine, Homelite, Honda, Huskee, Husqvarna, John Deere, Lawn Boy, MasterCut, Montgomery Wards, MTD, Murray, Poulan, Poulan Pro, Ryobi, Simplicity, Toro, Snapper, Troy-Bilt, Turf King, Weed Eater, Wheel Horse, Worx, Yard Machines, Yard-Man

Top Reasons Tiller Engine Runs Poorly  — Tiller Troubleshooting

Tiller engine stops? This video provides information on how to troubleshoot a tiller and the most likely defective parts associated with this problem. Commonly replaced tiller parts: Starter Assembly Pull Rope Gas Tank Fuel Line Carburetor Fuel Filter Air Filter Chain Tine Spark Plug The information provided in this tiller troubleshooting video is applicable to all tiller brands: Ariens, Bolens, Craftsman, Cub Cadet, Dixon, Echo, Exmark, Green Machine, Homelite, Honda, Huskee, Husqvarna, John Deere, Lawn Boy, MasterCut, Montgomery Wards, MTD, Murray, Poulan, Poulan Pro, Ryobi, Simplicity, Toro, Snapper, Troy-Bilt, Turf King, Weed Eater, Wheel Horse, Worx, Yard Machines, Yard-Man

Top Reasons Tiller Engine Stops  — Tiller Troubleshooting

Tiller engine leaks gas? This video provides information on how to troubleshoot a tiller and the most likely defective parts associated with this problem. Commonly replaced tiller parts: Starter Assembly Pull Rope Gas Tank Fuel Line Carburetor Fuel Filter Air Filter Chain Tine Spark Plug The information provided in this tiller troubleshooting video is applicable to all tiller brands: Ariens, Bolens, Craftsman, Cub Cadet, Dixon, Echo, Exmark, Green Machine, Homelite, Honda, Huskee, Husqvarna, John Deere, Lawn Boy, MasterCut, Montgomery Wards, MTD, Murray, Poulan, Poulan Pro, Ryobi, Simplicity, Toro, Snapper, Troy-Bilt, Turf King, Weed Eater, Wheel Horse, Worx, Yard Machines, Yard-Man

Top Reasons Tiller Engine Leaks Gas  — Tiller Troubleshooting

Edger starts then stalls? This video provides information on how to troubleshoot an edger and the most likely defective parts associated with this problem. Commonly replaced edger parts: Starter Assembly Pull Rope Gas Tank Fuel Line Carburetor Fuel Filter Air Filter The information provided in this edger troubleshooting video is applicable to all edger brands: Ariens, Bolens, Craftsman, Cub Cadet, Dixon, Echo, Exmark, Green Machine, Homelite, Honda, Huskee, Husqvarna, John Deere, Lawn Boy, MasterCut, Montgomery Wards, MTD, Murray, Poulan, Poulan Pro, Ryobi, Simplicity, Toro, Snapper, Troy-Bilt, Turf King, Weed Eater, Wheel Horse, Worx, Yard Machines, Yard-Man

Top Reasons Edger Starts Then Stalls — Edger Troubleshooting

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Top Reasons Edger Runs Rough — Edger Troubleshooting

Leaf blower starts then stalls? This video provides information on how to troubleshoot a leaf blower and the most likely defective parts associated with this problem. Commonly replaced leaf blower parts: Starter Assembly Pull Rope Gas Tank Fuel Line Carburetor Fuel Filter Air Filter The information provided in this leaf blower troubleshooting video is applicable to all leaf blower brands: Ariens, Bolens, Craftsman, Cub Cadet, Dixon, Echo, Exmark, Green Machine, Homelite, Honda, Huskee, Husqvarna, John Deere, Lawn Boy, MasterCut, Montgomery Wards, MTD, Murray, Poulan, Poulan Pro, Ryobi, Simplicity, Toro, Snapper, Troy-Bilt, Turf King, Weed Eater, Wheel Horse, Worx, Yard Machines, Yard-Man

Top Reasons Leaf Blower Starts Then Stalls  — Leaf Blower Troubleshooting

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Top Reasons Leaf Blower Runs Rough — Leaf Blower Troubleshooting

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Top Reasons String Trimmer Head Not Spinning — String Trimmer Troubleshooting

String trimmer starting, then stalling? This video provides information on how to troubleshoot a string trimmer that is starting and stalling and the most likely defective parts associated with this problem. Commonly replaced string trimmer parts: Air Filter Spark Plug Carburetor Start Pulley Pull Rope Starter Gas Tank Fuel Line The information provided in this string trimmer troubleshooting video is applicable to all string trimmer brands: Ariens, Bolens, Craftsman, Cub Cadet, Dixon, Echo, Exmark, Green Machine, Homelite, Honda, Huskee, Husqvarna, John Deere, Lawn Boy, MasterCut, Montgomery Wards, MTD, Murray, Poulan, Poulan Pro, Ryobi, Simplicity, Toro, Snapper, Troy-Bilt, Turf King, Weed Eater, Wheel Horse, Worx, Yard Machines, Yard-Man

Top Reasons String Trimmer Starting, Then Stalling — String Trimmer Troubleshooting

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String trimmer running rough? This video provides information on how to troubleshoot a string trimmer that is running rough and the most likely defective parts associated with this problem. Commonly replaced string trimmer parts: Air Filter Spark Plug Carburetor Start Pulley Pull Rope Starter Gas Tank Fuel Line The information provided in this string trimmer troubleshooting video is applicable to all string trimmer brands: Ariens, Bolens, Craftsman, Cub Cadet, Dixon, Echo, Exmark, Green Machine, Homelite, Honda, Huskee, Husqvarna, John Deere, Lawn Boy, MasterCut, Montgomery Wards, MTD, Murray, Poulan, Poulan Pro, Ryobi, Simplicity, Toro, Snapper, Troy-Bilt, Turf King, Weed Eater, Wheel Horse, Worx, Yard Machines, Yard-Man

Top Reasons String Trimmer Running Rough — String Trimmer Troubleshooting

Spark-Plug

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940 Spark Plug

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Common Problems Fixed by the Spark Plug

String trimmer won't start

Edger won't start

Leaf blower won't start

Small engine won't start

Small engine hard to start

Small engine runs poorly

String trimmer runs rough

Leaf blower running rough

Edger runs rough

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