why is my lawnmower keep stalling mountfield petrol lawnmower?

827m stalls when i try to engage cutting gear

David Carter
June 2022

I have a Ryobi petrol mower once primed it starts first time , runs for 3/4 seconds then cuts out . if I start it and keep pressing the primer very slightly it runs .

peter
July 2016

anyone know where i can see a diagram of a carb set up on a mounfield lawnmower, took it off to clean it and forot where the springs go back ,

mark
June 2013

my 10 year old mountfield m5 starts great, but when I pull up the lever to engage the blade nothing happens. And I can`t cut the grass. The blade wouldn`t turn. The cable is in good order and I can feel tension on the spring when I lift the lever but it doesn`t cut the grass. For some odd reason it is not engaging. Please help me out her$e!!! Many thanks.

Clive
March 2012

My mower was doing the same - frequent stalling and running really unevenly as well.
When I took the spark plug out it was heavily carboned up - I hadn't got a spare plug, but wire brushing the old plug and adjusting the gap made a huge difference - it runs beautifully now :-)
I hadn't got a feeler gauge to hand to set the gap properly so just set it until I could comfortably slide my thumbnail into the gap which seems to have worked

Rachel
July 2010

I had the same problem with the Briggs and Stration engine on the mover.
Now then if you have the more modern mover it has an automatic choke, the carburetor is in the closed position for start up hence the engine needs to be primed. Once started a small flap attached to the fly wheel is pushed back with the draft of the motion, this then opens the carburetor via a butterfly device inside the carburetor. At the top of the carb there is a plastic stop for the automatic choke sometimes the mechanism gets stuck on top of the plastic and then the butterfly in the carb will not open hence very rich petrol mix and no air, result the engine will try to stall and then run. Here is the solution
There are three set screws holding down the rip cord mechanism take these out ( put in a container so as not to lose them) lift off the rip cord mechanism taking care
to make sure the oil dip stick is taken out, If you wish you can take off the oil stick by undoing the two small screws that hold it.
If you look down you will see the fly wheel and the flap that operates the choke gently move the flap away from the fly wheel if it is stiff to move then the mechanism at the top of the carb will be stuck and will not move easy if so gently move the mechanism over the plastic stop and then if done it will then go easy, job is now done.

baz
May 2010

Hi just wanted to say thank you so muchx As a single mum I was just about to go and buy a new mower, but after reading the above comments thought i would give it a go. Got a spark plug and filter off ebay - £7.00 downloaded a manual http://www.smallenginewarehouse.com/images/manuals/GCV135-160.pdf

followed the instructions to change the spark plug and presto it is all working fine!!

again thank you so much!!!!

Louise
May 2010

just had this problem and fixed it easily. unscrewed the bolt holding the bowl and fuel for the float. it had water in it. cleaned it with carb cleaner and replaced it. removed the spark plug and turned the moter over to get any water out of the engine. replaced spark plug, primed, and started the mower.

jc
August 2009

i have just fixed mine (which had the same problem) by unblocking the fuel suction hole in the fuel chamber (tube with hole drilled in the side)

Dezza
May 2008

If your lawn mower is a couple of years old, it gets some dirt and debris caked up inside of the carb. If you simply treat your gasoline and clean out the carb, it should work fine after that. Also try to replace the small hose that runs from the gas tank to the carb. Simply use plyers to loosen the clamps and slide them away from the ends of the hose. Have a golf tee ready to insert into the end of the gas tank to keep the fuel from spilling out if your tank is full. Then connect the new hose and don't forget to replace the clamps from the old one. I'd also put an in-line gas filter in the middle of the hose to keep the junk out of your carb. This sounds difficult but it is really easy. Good luck

Joe
August 2007

It needs a tune up. New spark plug, oil and filter.

al
August 2007

water in the fuel

nick
July 2004

the bowl on your carb. is got water are trash in it. to fix it there is a nut in the center of bowl unscrew and ease it down spray carb cleaner in it and inside the carb replace the bowl after you clean it out and it will run fine

jemmotorsports@aol.com
June 2004