Electrical gremlin

Here's the link. Your ammeter is probably a little different. The important point is make a very solid electrical connection between the studs and the metal plate. it may have to occassionally handle 40 amps, and will routinely handle 10-20 amps - although for only a minute or so.
Bullet-Proof Your Ammeter (A 'How To')

After you make the fixes and get votlage at all the places that should be hot, remember that does not guarentee good connections.
To test for low resistance connections, you will have to flow current through the circuit of interest and see of there is any measurable voltage drop.