I have just reconnected the guvernor on an old Suffolk Punch cylinder motor mower and it runs satifactorily - centrifugal clutch operation is OK, so is drive. However something flew off when I first operated the throttle lever and vanished; now I have to hold the throttle open all the time to get drive. What is missing and how can I replace it/fix it please? Also the engine was so full of oil it blew it out everywhere; how do I guage the correct oil level? Filler cap or drain plug level?

Alan, June 2009

Thanks John; great information. My mower's a 43SL with a square oil drain plug (horizontal) and an angled filler plug (plastic) both on the back. I can find no dip stick - front or back. Where should the wavy washer be located on the throttle assembly? There's a trapezoidal opening and spigot hole in the housing on the right side. Is it there? There's no sign of anything having been mounted axially & I haven't taken it to pieces and lost anything.

Alan, June 2009

You've lost a friction washer from the throttle lever - this is a spring washer which is wavy in section, and it holds the lever steady. As for the oil level, does your motor have a dipstick at the front, with a square end drain plug?

John, June 2009