Yes Jeff no blockages at the torch end, liner is clear, but the groove in the feed roller is shot, and is almost as deep as the wire is thick.
Since I've had this welder, which is a good few years, I've been unable to remove the grooved roller - it should be held on by a washer and knurled screw which are missing (replacements made this morning) and then just pull off the 10 mm gearbox shaft but it was rusted / jammed solid.
Yesterday I made up a puller and got it moving slightly but it was very difficult with the wire feed in situ, so I took the entire unit out so that I could work on the bench with better access and visibility. It's now all cleaned up and back in the machine as I can now remove the feed roller at will.
If Migatronics or their agents don't come up trumps I'll convert it to rollers from another maker. So long as the rolls are approximately the same diameter (35.2 mm about) and the bore is 10 mm I'm sure I can sort out the connection issue, as there are two small flats on the 10 mm shaft that engage in that odd shape on the gear, and it will just need a suitable / similar bit fixing on the replacement.
I tried a file on the original roller this morning - very hard but I'm sure carbide inserts would cope. But as the groove is now so deep I think it's a close run thing if skimmed that the gears won't bottom out before the wire is pinched.