Flymo Quicksilver 46S starts but then dies?

Well i had a similar problem although it wouldn't start at all and the answer above was spot on.
The filter was full of oil, which I washed in warm soapy water, and replacing the old fuel gave an immediate start.
Thank you

Biro
April 2011

Could be that your fuel has gone stale? (yes, in just 5 weeks unleaded can go bad!) try replacing it with fresh.
Did you tip the machine on its side? tipping a Briggs and Stratton engine side ways with its exhaust down/carb up will fill the timing cheast with oil. when you try to start the engine this oil is forced into the carb and aircleaner and bungs it up stopping the fuel flowing properly and also causes the symptoms you describe. Remove the air cleaner and if it's very oily, clean it and the carb.
Water in fuel? If the machine is left out in the rain, it will very likely have got into the fuel tank (if it's not got there from your can that is!). Again stripping and cleaning the carb is the only long term solution.
All these problems are user related and not warranty repairs I'm afraid. If there is no oily air cleaner, your fuel is new and you cannot see water in the fuel (use a battery powered torch to look in the tank as water forms blobs in petrol and can often be seen with a light), then it is probably best to return it to your flymo agent for them to check out. (if you bought it from catalogue/B&Q etc you will need to take your receipt. Hope this helps. Briggs are one of the best engines in my opinion but they are sensitive to being tipped up the wrong way. Always carb down or sparkplug up. fuel WILL leak from the tank cap when you do this, a polythene bag over the filler hole with the cap screwed down on top can reduce this quite a bit.

Jules
July 2010