Join Date: Nov 1999
Location: Central California, USA
The solenoid has to overcome a return spring, and whatever friction the starter drive has, also, inside the solenoid, right under the cap is a small, very stiff spring that stops the plunger travel. Right behind the cap is a copper washer that strikes the top and bottom starter terminals engaging the starter.
Several things can go wrong. The solenoid can fail if the washer eventually hammers and arcs on the heads of the two large contacts. If you look at the solenoid cap, where the attachment screws are on each side, they protrude into the washer area, and the washer will hit this bump inside the cap if the contacts wear a little.
If the cars electrical system is not up to par and can't deliver enough voltage to the solenoid, it won't engage the starter.
Also, if there is anything wrong with the starter that would cause it to draw too much amperage, like worn brushes or dragging armiture, it will cause the starter to chatter. GM has a weaker solenoid return spring that helps some starters work.There are some high heat solenoids too. Others use a ford type remote solenoid triggered by the starter switch.
I like the mini starters, I found a rebuild shop in Reno NV that sells them for $100.00 They were selling them at the GoodGuys carshow at Pleasanton, CA. I can get you the info if you are interested.
On the location of the neutral safety switch. The switch is on the steering colum for colum shift cars. And on the shifter for console shifter cars. I'd find where the switch is or was, and make shure it is bypassed. A little extra resistance in the connection could cause your trouble.
Also make shure your starter or solenoid is not just worn out. A lot of normal wear problems, bad connections, etc get blamed on heat soak.
[This message has been edited by davidpozzi (edited 03-08-2000).]