Welding Tips and Tricks

My trusty Miller 251 has developed a stutter. It worked fine 2 days ago, then yesterday it began cutting out. I start the arc fine and I'm pushing along and the arc just quits momentarily then restarts. I'm welding at 18 volts and wfs of 250 ips. I haven't changed any settings since 2 days ago. I suspect the wire feed somehow because the wire does not stub into the work. Also, the wire doesn't burn back to the tip either. If I am patient and stop my forward progress and keep the trigger pulled, so far the arc restarts and I can continue welding. Any ideas appreciated.
Joe

The liner is dirty. Probably just as cheap to replace it with a new one.

Thanks for the idea about the liner. That might be part of the problem. I'll look into it. But I think I improved things a lot by methodically going through and cleaning the rollers. I found them to be a little dirty. After cleaning them most of the stuttering cleared up.
joe

Try blowing some air under low pressure from the gun end to clean out your liner also.

could also check the spool and make sure the wire is not crossed up.

Thanks everyone for the suggestions. I'm up and running again after cleaning the rollers and making sure the wire on the reel wasn't crossed up. It's just something I had never run into before. I'll know what to check next time.
Joe