3300 series no start

[kuzin eddie]

I have replaced the glow plug relay and starter relay when I turn key to start position the glow plug relay hums and vibrates loudly. Still won't turn over, Ideas? I'm leaning towards ignition switch.

 

[lugbolt]

bad ground.
loose connection
bad connection

those are my guesses

 

[Dave_eng]

I have replaced the glow plug relay and starter relay when I turn key to start position the glow plug relay hums and vibrates loudly. Still won't turn over, Ideas? I'm leaning towards ignition switch.

Look at the following images and then check to see if your tractor has any of the same........ repair ends on cables and poor connection point to frame for ground cable.

Do you have a multi meter. if so DENSO has provided a great series of test for No Crank conditions which I have attached.
Dave