OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Walk Behind Lawn Mower Frames Victa Lawn Mower Frames Victa Commander wont start

The spark plug is sparking, the carby is ok (I think).
The problem may be that round silver thing that screws into the head (vacuum pump?)
It had muck and grease in those 4 holes and when I cleaned it and put it back the motor fired and ran but stopped as the fuel tank was not connected.
After putting everything back together it won't start. It just hisses.
What does the round silver thing do?
Should I replace it?...Can you help me please

long_grass,
If it is making a hissing noise then you should replace the decompressor as it has a valve in it, which releases the pressure so that it is easier to start.

Regards,
Victa Man