Expert: Mike Evans - 9/14/2009

Question
but in new battery starter cables alternator the car starts sometimes,but othertimes nothing. can use small jumper wire on battery to starter and it works.whats wrong? terry

Answer
    I assume that by not starting you mean not cranking.  If you changed the cables, did you make sure that the ground is good to the block and the frame?  It's usually a good idea to have a ground cable going to the alternator bracket, as most Chevys have, and another one going from the engine block to the frame.  It is usually in the back, but it can be anywhere.  You didn't say anything about changing the starter, or the ignition switch.  Given the age of the car, and the fact that jumping to the starter gets it cranking, I would be very suspicious that the switch is bad.  You get this a lot on old cars, the contact area where the switch energizes the starter circuit just wears out from the contact wiping back and forth over it year after year.  Try rigging a push-button switch to the back of the ignition switch to jump it.  If this works when the key switch doesn't, then the key switch needs to go.