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SIERRA 18-8821-1 Spark Plug Wire Set for Mercruiser Stern Drives

Model # 7862840Mfg # 18-8821-1


Customer Reviews
In stock online.

Product Description

  • replaces: Mercury Marine 84-813720A3
  • replaces: Mercury Marine 84-813720Q4
  • replaces: Mercury Marine 84-813720Q3
  • replaces: Mercury Marine 84-816761Q4
  • replaces: Mercury Marine 84-813720A4
  • replaces: Mercury Marine 84-816761A4


by PowerReviews
SierraMagForce Premium Marine Spark Plug Wire Leads

(based on 1 review)

Ratings Distribution

  • 5 Stars



  • 4 Stars



  • 3 Stars



  • 2 Stars



  • 1 Stars



Reviewed by 1 customer

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Great replacement for OEM wires

By Captain Ed`

from Columbia, SC

About Me Advanced

Verified Buyer


  • Quality


  • Instructions

Best Uses

  • Large Boats
  • Small Boats

Comments about MagForce Premium Marine Spark Plug Wire Leads:

The boots fit very tightly on the distributor and the spark plugs. It would be nice to have known which end of the wire was to go on the ditributor and which end was to go on the spark plug.

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