1986 Ski-Doo Factory Shop Manual, Page 370Get this manual
Section 04 ELECTRICAL SYSTEM Sub-section 03 (SPARK PLUGS)
DESIGN SYMBOLS USED IN NGK SPARK PLUGS
First Iette prefix fo th re ad and helegon: size Secondthird letter prefix for construction featureellcept sing Ie refi K
COf'!I1 rUC:lioo future
Heat rating number
First Ienel sulli for Ihread: reach
Sellond leller suHill for construction feature, etc
Hr!Xil'gOll
sr.u 20.6 mm
iim 16.0 mm
l'hnuul filch
CO'I'lIUF"UII::tkm toa1utllJ', e1:t:::
dl 1e 01011
Ha)!6gjCttI
HIII aoon aid :2:3.8
1'9.0mm 23.S mm
CoI!!m "101 15 HORTY 1
ComoaCl 'lipIflANTAMI
Pro,acted
RuJItCl' IYp
g,501'" flhrald di-a14 mml
NQII'III
SPSpoocIoIPIlQIot _
Cont9!1Ul1Dn [yilt!
.1'F112" .14"")
lRacll'Ql pl4.KJ,Jcentllf 1It!oc-
tfOde 01 SUKkwl mnaT Roei"ll plUjll, nidAl 01110_
nOD lVlltl
1'.Omm IIh d"1IS", mml