The Bible tells us---
" Where no counsel is, the people fail : but in the multitude of counsellors there is safety. " ( Proverbs 11:14 )
So to prevent you from failing Spark Plug reading here is a multitude of counsellors in picture form.
I got all this from a Free hand out I recieved from NGK Spark Plugs back in 1977. I think their Hot-but-OK plug pictures are a bit too hot for me. But who am I to nay say NGK ? Enjoy !
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| 1 Oil Fouled |
2 Oil Fouled |
3 Carbon Fouled |
4 Too Cold |
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| 5 Too Cold |
6 Cold or Rich But OK |
7 Cold or Rich But OK |
8 Cold or Rich But OK |
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| 9 Good |
10 Good |
11 Good |
12 Good |
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| 13 Real Good |
14 The Best |
15 Best |
16 Best |
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| 17 Best |
18 Good |
19 Good |
20 Good |
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| 21 Kinda Hot But OK |
22 Hot or Lean But OK (?) |
23 Hot or Lean But OK (?) |
24 Hot or Lean But OK (?) |
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| 25 Too Hot or Lean Pre-Ignition Range |
26 Too Hot or Lean Pre-Ignition Range |
27 Too Hot or Lean Pre-Ignition Range |
28 Too Hot or Lean Pre-Ignition Range |
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| 29 Too Hot or Lean Pre-Ignition Range |