[donald]

Have a century 90-105 mig 115 volt, using mixed gas, solid wire, 10 years old but used very little. most of the time i get a good clean buzz/weld but then some times right in the middle of a clean buzz/weld the buzz stops and I only get a hiss with no penitration, the weld just make a puddle with some times a little pop. Is this a common problem ? I dont know if I have a problem with the welder or ? I assume it cant be the setting as it welds perfect most of the time on the same setting. thanks for any help.

[AKmud]

Sounds like your ground is intermittent. Make sure you have a clean area to clamp to. MIG likes a good connection.

[Mike]

Welcome to the forum Donald.

[Superiorwelding]

Donald,
Sounds like you have a wire feed issue, if I am understanding this correctly. When is starts "hissing" can you tell that the arc has moved back toward the tip and the puddle does not seem to be filling in? If so check your tensioner both for the rollers and spool of wire for slippage or your liner/gun for problems.
-Jonathan