Hi all,
Update, took the top fan off to check and points look ok, the only seal i could find was a small foam one round the spindle, crank bearings are ok, replaced and tried again.
Now I seem to have found a 'trick' to keep it going which might give someone a clue, as its about to die if i pull the throttle back to stop position(the stop wires aren't connected) it comes back to life then i can push the throttle forward again and keep it goin like that??
At least I've got all the grass cut now!