Husqvarna SM 610 2006 Workshop Manual page 191

E L E C T R IC S Y S T E M
S p ark p lu g
U se "N G K " C P R 8 E spa rk p lu g. C he ck d istance "A " (0 ,6 ÷0 ,7 m m /
0.02 2÷0.02 6 in .) b etw e en electrod es. A w ide r gap m a y ca u se d ifficu ltie s
in sta rting e ng in e a n d in ove rloa din g coil. A ga p that is to o n a rro w m a y
cau se d ifficultie s w h e n accelera tin g , w hen idling th e e n g in e o r w h e n
pe rfo rm in g a t lo w sp ee ds. C lea n the dirt a w a y fro m th e b a se o f th e s p a rk
plug b efore re m o vin g it fro m the cylinde r. It is very use fu l to e xa m in e th e
state of th e sp ark p lug just afte r it has bee n rem ov e d fro m th e e n g in e
sin ce the d ep osits on th e plu g and the co lor of the insu la to r p ro vid e
use fu l ind ica tion s co nce rning th e h e at ratin g of th e plu g , ca rb u re tio n ,
ig nition a nd g en e ral e n gine co ndition. B efo re re fittin g th e p lu g , th o ro u ghly
cle an th e insula tor u sin g a bra ss-m etal bru sh. A p p ly a little g ra p h ite
gre ase to the p lu g th rea d; fit a n d screw th e plu g h o m e b y h a n d a n d th e n
tigh te n to th e co rre ct to rque (10÷1 2 N m ; 1,0 ÷1,2 3 K g m ; 7 .2 ÷8 .9 ft-lb )
using a p lu g spa nn er. S p a rk plugs w h ich have cra cke d in su la to rs or
corrod e d e lectro de s sh ould b e re p lace d.
N e u tral p o s itio n se n so r c h ec kin g
W ith the g e ar in ne utra l position (fig .5 ), detach th e co n n e cto r (1 ) o f th e w irin g of
th e n e utra l sen so r, g rou n d a tester term in al on the e n g in e , th e n in se rt th e oth e r
on e in the h ole w he re is the ne utra l senso r. T h en c h e ck th e co n tin u ity.
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