[rksuri16]

Hi,
I had a similar problem and it was found that the starter needed overhauling. SLotting of the armature is needed as the same has got worn out and the copper strips are very near one another and on heating up some of them shaort or spark jumpting takes place and the starter doesno take load.
Just get the armature slotted and the problem shall be solved.

with best wishes
Ramesh