[Roadsters] 67 Roadster

[richard bush]

My car has been slow in starting. It won't start via the battery but the lights do work so I don't think it's a bad battery. I am able to start the car by jumping it down a hill but the last time i did this, it overheated, a bunch of green stuff came out of the radiator and now it won't do anything. No engine turn over at all and frankly, I am afraid to try and jump it again. Admittedly, it's been hot here - over 100 most days but I have driven it in the heat before. 
I am clueless about what to do as are the mechanics I have spoken to. Any input would be most appreciated and please, speak to me as if I were a 8 year old.
Finally, I will have to fill the radiator. What do I use to fill it? 
As always, thanks and best regards,
Rick
R A Bush, 4806 Eck Lane, Austin Texas 78734/cell: 512 574 8081