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 Ground Advantage Mail with Tracking


When buying different variations from the same or similar listings, the lowest shipping cost is obtained by buying the total number of units wanted from 'One Variation' and then leaving a message within your order defining what items you want to receive and the number of each item you want to receive.   The number of items requested cannot exceed the number shown as being in stock.  This stops eBay from restarting the total weight summation for each variation. 

The message link is on the same page where you select method of payment.USPS postage cost is based on total weight and zip code. The cost breakdown is shown before payment is required and the discount for multiple purchases is shown as a separte credit in the list.