Gap Mower Spark Plug
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You’ll find useful resources on this page, tips, links to tools, parts and supplies required to complete your repair.
Gapping the plug is a simple job when you know how, and it will make a huge difference to how your mower performs.
If the plug gap is too small the spark won’t be large enough to ignite the fuel mix. If the gap is too big, the spark will occur too late, if at all and puts a heavy load on the armature (coil) possible causing it to fail prematurely.
This video will have you gapping like a pro in jig time.
Before working on your mower be sure to remove the plug wire to prevent accidental starting, see “Repair Safety Video”.
Tools & Parts
To nail this procedure you may need the following tools, parts and supplies.
Ratchet Tool Set
Before we can do anything, we'll need tools. I've selected this set as I own some Craftsman tools and while I have worn some out, they did do a ton of work. So I expect this set will last the occasional user quite a long time.
This set carries both metric and standard sockets and that's important, because some mowers will have both type of fastener sizes. Includes spark plug sockets. Picture links to Amazon.com
Wire Brush set
John Cunningham is an Automotive Technician and writer on Lawnmowerfixed.com. I've been a mechanic for over twenty years, I use my knowledge and experience to write "How to" articles that help fellow gear-heads with all aspects of mechanical repairs, from lawn mowers to classic cars.