why is my ground wire arching

ive had my car down installing a new cam in the 70 mav 302 and ive unhooked the hot battery cable and the ground cable cause I was also touching up the paint on the engine itself ,it also has a body to block ground wire which I 1st hooked up and when I went to hook the battery ground wire up to the block also it arched lik e it has juice to it ,now note also that the hot cable still isn't hooked up whats going on here am I just having a brain freeze or what have I done wrong

 

Battery in backwards?
I was going to say that the HOT wire to the alternator was touching the frame but now I'm Frain Brozen too...

 

battery isn't backwards but the alternator wire possibly might be touching something it isn't hooked up yet gonna go out to see if its touching metal somewhere

 

I went out and checked the alt. wires aren't the problem,i might try taking the ground wire off my 72 grabber to see if I have a bad ground wire

 

alt. wire shouldn't make a difference if the positive post isn't hooked up.

 

Correct! Watching this subject. Very interested in the outcome.

 

If the positive isn't hooked to the battery, there is no way you get a spark.

 

Dave u r correct ,I had to go to bed and rethink my work.the battry hot cable is unhooked from switch not the battery and I remember I have a wire from inside the car attached to the battery hot cable,im thinking this little wir eis attached to the voltage gage inside the car could this make more sense?could this make it arch when I try to reattach the ground wire,i have to leave this morning but when I return home ill do some more investigating.

 

You will get a small spark when the dome light comes on if the door is open. A stereo system memory will cause a small(er) spark

 

rthomas771 it has a cd player in the car didn't know a stereo system would make the ground wire arch like that

 

anything having a continuous feed will generate spark...