1981 Ski-Doo Shop Manual Supplement, Page 14Get this manual
SECTION 02 SUB-SECTION (04-06)
1981 BOSCH SPARK PLUG CHART
ENGINE TYPE ELANSPIRIT 250 CITATION 3500, MIRAGE CITATION 4500E, MIRAG IIiE CITATION SS, MIRAGE SPECIAL NORDIK EVEREST 500E, FUTURA 500E FUTURA EVEREST LCFUTURA LC BLI ZZA RD 5500lGP SPECIAL BLIZZARD MXGRAND PRIX MX BLIZZA RD 7500SUPER SONIC BLIZZARD 9500ULTRA SONIC ALPINE 640 ER ELITE 247 277 377 377 377 503 W275 T2 (W3C) 464 503 503 354 W300 T2 (W2C) 454 640 464 M240 T1 (M4A2) W275 T2 (W3C) 0.40 mm (016") 0.50 mm (,020") 0.40 mm (,016") 0.40 mm (.016") 0.40 mm (,016") 0.40 mm (,016") 0.40 mm (,016") SPARK PLUG NO M175 T1 (M7A) SPARK PLUG GAP 0.50 mm (,020")