im trying to build a simple glow driverthat i can leave attached to the engine and turn it on and off at the flick of a switch. ok all good there. but the problem im having is that the only battery i can get to light the plug is the nicad that came with a proper glow driver. i have tried ordinary batteries but they dont work, ive tried single AA, C, 2 AA but none work. just the nicad c cell. Any reasons for this??? im stumped.

I mounted two Elite 1700 AA from cheapbatterypacks.com with a switch
and charge jack. Tested to run 50 min. (in parallel) with enough glow
to start. These cells are rated to dump 15-25 amps. They are NIMH.

A glow plug will draw between 2 and 4 amps, which is quite a bit. The cells you are using just can't put out that much current.

You need at least a "C" size cell, or multiple smaller cells wired in parallel.

AV8TOR