CHAMPION SPARK PLUG CJ8 #843 #843-1 Replaces RCJ8 CJ11 HT10J 018-3015-8 J91 JT8 JT8J UCJ7G UCJ8G BM4A BM6 BM6A BM6A10 BM7 BM7A BMR4A 5628 5728 5921 6321 6521, SELECT: Card or Shop Pack


  • Champion copper plus small engine plugs resist fouling and provide superior corrosion resistance

  • Feature a copper core electrode that provides increased conductivity and heat control while delivering good overall wear characteristics

  • Engineered to exceed OE designs and maximum durability

  • Designed for easy starting


  • Plug Type: CJ8
    Seat Type: Gasket
    Hex Size: 3/4 in
    Thread Size:  14 mm
    Thread Reach: 0.375 in
    Installed Height: 1.5 in (shorty)
    Gap: 0.027-0.033in   (0.69-0.84 mm)
  • Heat Range: 8
    Center Electrode Material: Nickel Copper Alloy
    Ground Electrode Material: Nickel Copper Alloy
    Classification: Champion Copper Plus Small Engine
  • Insulator Material: Zirconia Enhanced
    Resistor Plug: Non-resistor

MPN: CJ8 #843
UPC: 037551011094

Shop Pack plugs are from a Bulk Shop Pack and are shipped wrapped in individual bubble wrap units.

Purchase is for one spark plug.

USA domestic shipments are shipped USPS First Class Mail with Tracking

International shipments are shipped USPS First Class International Mail with Tracking