[Motivator]

Hi my sister has this mower . And for some reason it has started running rough . It has a Briggs engine . From what i have read it could be a carb issue .  It was running fine when last used a month back . Now it seems to be misfiring .

[Gwiz]

Does it have the Briggs "Classic" engine with the red push primer to start? if so, replace the diaphragm and clean the petrol pick up tube at the same time.

[Motivator]

Yes thats the engine . Red primer button .  Was running mint now running awfull.

[Gwiz]

It sounds like the usual problem. Also check the oil level or better still replace it.
SAE 30 grade, 500-600ml. I think the diaphragm is about £2.50p-ish.
When you've got the carb of the petrol tank, wash the tank out with a bit of petrol to make sure there isn't any muck in there.

[Motivator]

Thanks Graham . I thought that would be the problem .  Will have to get the part sorted .

[Flatcat]

We have the exact same mower, but the hand propelled version

Our diaphragm got replaced in the service, so if you are taking it to the shop for repair, then an all round service would do it good as it obviously hasn't had one for a while 

[Motivator]

Worked a treat . Thanks all..

[andyw]

I've got an old 2hp briggs engine and this was having issues, I took of the carb and sprayed a load of carb cleaner in there, now it runs ok, well ok for an old machine.