Old mower died, was given one not used for over three years, is from Kmart, a Briggs and Stration 5 hp engine push mower....cleaned it up, changed the oil, plug, filter and all new gas. Will now start but will not stay running, what now?

br, September 2007

i am having the same trouble, my snapper mower, will run for a couple of seconds with a squitt of gas in the carb but wont stay running. i cleaned the carb twice and for what ever reason the prime does not work. i cant seem to get any gas to the carb, there is plenty of new gas in the tank and it fills up the carb bowl . Any suggestions, thanks

gary, April 2010

Change the diapragm. Guaranteed fix (assuming you also clean out any accumulated crud and WATER from the carb while it's in bits). If you get it apart and discover it has internal rust due to being stored with water (possibly condensation) in the carb, the the only option is ultrasonic cleaning. Only had to resort to this ONCE in 1 years.

Phil Saunders, November 2007

After going deeper into the problem of starting then stopping, I fitted a new gasket and diapragm in between the carburettor base and the tank. Part Number of gasket set is 495770, costs £4.95 in the UK. from Squires Garden Centre. Problem solved.
Jack

Jack Rogerson, September 2007

Hi
I have exactly the same problem as you have with 2 mowers. One is a Haytor Sprite, and the other a Briggs and Stratton. They both use engines with similar carburetors. Both mowers will not prime, when the rubber bulb is squeezed repeatedly. The Haytor however will start if I squirt a small ammount of petrol into the carburettor intake before trying to start it. It runs for about 5 seconds and then stops. If, hovever I continue to squirt more fuel into the carburettor before it stops, it will run for longer, or until I stop squirting more fuel in. After about 3 or 4 attempts, it will continue running on it own, and I am able to cut my lawn.
The Briggs and Stratton mower also starts by doing the above, but will NOT continue to run, ever.
If you try this, use a syringe or similar to inject the petrol, DO NOT pour in it from an open vessel, as it IS petrol, and could possible ignite.
Lets hope someone else can throw more light on the subject.
Jack

Jack Rogerson, September 2007