JD Model 50 Won't Start

[JDRULES]

My Model 50 was starting just fine but the dual 6 volt batteries were old and in decline so I replaced them with a new set of 6 volts. Now when I step on the starter, nothing! The 鏑? 釘? and 泥 light switch positions all appear to work correctly with bright and dim lighting, so I知 getting juice off the new batteries. Has anyone run into a similar situation with these series tractors before or does anyone know what I may have done wrong and what I need to check?

 

[buickanddeere]

Is the polarity correct ?do the lights dim when attempting to start. A ground connection to the battery box is usually rotten. Run the ground down to a main casting instead of to the battery box.

 

[JDRULES]

Thank you Sir. I'll check it and will give it a try