I'm working on a 75 240D with the separate ignition switch and starter switch (salt shaker glow plug indicator). I cannot get the starter to turn over the engine. Battery is new, correct for car and fully charged. I've replaced the starter and it had no effect. The glow plug indicator will glow but when I pull the switch to the start position, all lights and indicators go out. I've hooked up a remote starter switch to the + battery terminal and the small starter electrical connection and can hear the solonoid clicking on and off, but the engine still doesn't turn. I can turn over the engine manually (I jacked up a rear wheel, put the transmission in 4th and turned the wheel, which turned the engine.)

The problem started intermittantly. The car would be turned off and a few minutes later would not start. We would wait awhile and then it would start. Now it doesn't start at all.

I'm now at a loss for ideas......Any suggestions? Thanks!
Scotty