G’day Nzboon
Once the clutch is released and the mower is moving the usual method of speed control on these is through the throttle.
I have a very similar model and I found that there had been a few alterations over the years that needed to be put back to original specification in order for me to have it work correctly. You might have to do a bit of tinkering to get the rev range correct.
The first thing is to ensure that the choke is engaging and disengaging correctly with your start up procedure. If the choke doesn’t fully disengage then you’ll always have issues.
Next check the idle speed, this will be the speed the engine runs at with the throttle in the lowest part of the range. Disengagement of the clutch in this position would stall many of these machines, it should just be ticking over. There’s an idle adjustment screw on the carb that lets you set the idle.
With the idle correctly adjusted you can then set the throttle adjustment so that it’s linear from tickover through to full revs. You’ll need to have a read of the specific manual for your model of Briggs and Stratton engine to determine exactly which screws perform what function on your particular carburettor.
Mine is powered by a Kirby engine so I can’t assist with the specifics of which screw does what aside from explaining the process. I found I needed to rebuild the carby on mine as it was full of congealed gunk and the float was corroded and required replacement.
There may be someone on here who has better information on this particular engine.
Cheers
Ironbark
