my mountfeild sounds as if it ts going to stop then kicks out some ?

Assuming this is the model with a primer button on top of the petrol tank the problem is with the Carburettor diaphragm. These cost about £2 and you have to remove the fuel tank, take off air filter, remove 2 bolts holding tank usually 13mm and 10mm. Unhook little governor wire from linkage, remove whole thing from mower. Remove Carburettor by taking out the 5 screws, lift off and the there is the diaphragm, remove and refit new one, reverse operation to reattach to mower. Should take about 20 minutes.

Graham.
November 2009