1999 Mercruiser HI-Performance GM 377 EFI Engine Service Manual, Page 49Get this manual

1999 Mercruiser HI-Performance GM 377 EFI Engine Service Manual, Page 49

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TROUBLESHOOTING

Pre-Ignition Damage
Pre-ignition damage is caused by excessive high temperaturesCenter electrode melts first, followed by ground electrodeNormally, insulators are wh