Found the post was spinning a bit on the 1950 olds 303... With a bit of wrench pressure it has stopped but I don't believe it "fixed".
a square head contact, only accessed through disassembly. in a pinch you can cut a slot in the end of the copper "bolt" with a hack saw blade to hold with a screw driver while tightening the nut against the solenoid body
Thanks Paul... Though I might get this fired off today, but between the suspect post... and using jumper cables(likely the biggest issue) it just didn't happen. The engine turned 10-20' and stopped and gave a puff of smoke from the ground. I'm going to try and get a few leads made up tomm. is this a challenging disassembly?
That's the solenoid, not the starter, it can be replaced independently from the starter, though you'll have to remove the starter to do it, which shouldn't be a big deal. (note: always disconnect the negative lead from the battery first before putting a wrench on that positive terminal to prevent unintended arcing).
Here's something "most" guys are't aware of; if you disassemble the solenoid parts under the plastic cap, you'll find a large "copper" washer. Under the washer will be the two contact points corresponding to the two large posts you see on the outside. Loosen the two posts, and rotate them 180 degrees. As you do that you'll notice the arcing wear the washer has made while making contact. There's where most of the wear is in a solenoid, and most can be saved just by rotating the posts. I'm sure there are just as many guys that don't know this, as there are that do. I am Buitch/56sedandelivery.
Thanks 56'... I'll be trying that out. I've seen a few diagrams that illustrate what you've described.
It's been a loong time since I disassembled a GM solenoid, but I think as well as rotating the posts you can flip the big washer... PS...it's no more challenging than field-stripping your blender to wash it, and you are not going to be greeted with a shower of tiny parts rolling away either.
the slotting and tightening works for a while , long cranking heats them up and that causes them to expand and then loosen the nuts when they cool . the old selenoids are not rebuildable at home as they are rolled together vs the new style which have a bolted cap