300tdi starting problems

Hi
We have a discvery 300tdi.

Since we had the car the glow plug light has not stayed on very long, we have changed the glowplugs and the timing relay but this problem stayed.

Last week it refused to start, we charged the battery and eventually, after a lot of heating the glow plugs, it started.

It got worse and worse at starting. It was turning over but not firing. when we were trying to start it yesterday it stopped turning over and now all we hear is a tick.

If we turn the ignition now the last glow plug sparks, and positive battery terminal smokes.

We think we prob have an earthing problem but were wondering if it may be the starter motor? We dont know how to fix an earthing problem.

Any suggestions would be greatly appreciated.

Rach x

have you tried the earths on the starter motor?

or even the starter motor itself

try running another earth from the gearbox to the starter motor see if it makes any difference

Thanks for the reply
We did have a bad earth on the starter motor. Also had to re solder some connections on the 'spider'.
Finally, running good!