NGK TR5IX Spark Plug, Mercury 8M0046007
- Brand:
- Quicksilver
- Part no:
- 8M0046007
Where to buy
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This is the NGK TR5IX spark plug, supplied under Mercury part number 8M0046007. It is new, genuine Mercury Marine and Quicksilver stock. It supersedes the earlier numbers 861644 and 803990, so a plug marked with either one maps to this part. Nothing further is stated about gap or thread, so check those against your engine's manual.
Our take
The TR5IX carries two superseded numbers, 861644 and 803990. If the plugs in your engine or spares bear either one, they point to Mercury 8M0046007, which makes matching a replacement a simple number check.