Macot Petrol Push Mower. Briggs And Stratton Engine

You are viewing a used Mascot (made by mountfield) 42hp with a briggs and stratton 325 classic engine. The mower weighs approx 25kg, it has 5 cut heights, with the blade approx 16 . The mower is a push mower. The mower is being sold as spares or repair as it will only run for about 10 seconds then cut out. I have no idea why and have now purchased a new mower so no longer require this. I am sure someone will know how to fix this. Happy bidding, cash on collection only