Lawnmower advice

Sorry if this appears twice but it doesn't seem to be showing up on the message lists.

I have been given a petrol lawnmower, it is a Mountfield Laser Omega 46cm, powered by a Briggs & Stratton Classic 35 engine. The lady who no longer wanted it said "it just stopped working". I took it home put some petrol in it, primed it and pulled the starter string, after two tugs (oooh err!!) it burst into life. After using it for a few minutes (half a lawn) it stopped, I could start it again if I watied a few minutes and primed it again. It did this a further two times. There is no manual with the mower so could somebody give me a clue as what may be causing the problem?

Many thanks

John

Does it have a choke and if so, is the choke disengaging when it's warm?

Yes, this is the second version!

You may be using too rich a mixture - by inadvertently keeping the choke on all the time.

If it's like mine, the choke comes into operation when the throttle lever is moved as far as it will go, a bit beyond full throttle. Moving it back a bit once it has started takes the choke off but still enables the engine to run at full speed. May be worth a try.

Is the vent hole in the petrol cap blocked ? Rgds

No checked that as it was my first thought. I am thinking it is some sort of fuel starvation rather than electrical.

Thanks anyway

John

How did it stop? A sudden total cut out, or afew splutters then it dies?

Two things to check initially- firstly you still have a spark immediately it stops (carry a spare plug in your pocket and attach to lead & earth, spin engine look for good spark)

and secondly is the little hole in the primer bulb blocked?

Tim..

Thanks for all the advice, it seems to be OK now, the air filter element was choked up with grass. Cleaned it and soaked it in oil and all appears fine today. Used it for over 1/2 hour cutting in laws lawn only stopped when I needed it to, and they got their grass cut!!

Thanks

John

Right. So it stops after it gets warm right?

Too little fuel? Sometimes petrol filters and jets get clooged and as teh choke cuts out, it just leans down too much to go..ot ot could be blocked jets or filters...

Too much fuel? Choke may be sticking on..

Electrical fault? Smetimes components die intermittently at high temp. Normally electrical is a complete abpubt transitin from go to no go.

Fuel issues ytend to be more a dying away sort of thing with sometimes teh odd cough and backfire.

Sterip down and clean the carburettor and replace all filters with new, and wash the tank of years of silt and rust, and try again...