arcing across head to expansion chamber

GoldenMotor.com
May 28, 2014
208
25
18
Scottsdale, AZ
I noticed tonight a small arc going across my head to my expansion chamber, keep in mind it is very tight between the two only maybe 20-25 thousandths. why would this be happening? Bad ground or is the spark running throughout the head, its a fred head
 

crassius

Well-Known Member
Sep 30, 2012
4,032
158
63
USA
spark should only be inside the chamber - outside means bad plug, bad boot, or bad wire