Picked up a Victa VC300, petrol obvious leaking onto the base. Replaced the primer cap and associated oring. Runs fine however when you turn the fuel tap off, the mower doesn't stop running after a few seconds as it normally does with a Powertorque. The throttle control works fine and the mower turns off when using it. So what's at fault here? Btw this is a Mark 1, the one without a decompressor.
