Hi Sapper,
they're a weird set up. I had that problem years ago. Once they start slipping it gets worse as they start chewing aluminium out and you find filings settling at the bottom. The ends of the starter pawls can wear too and start becoming round on the tips. You can turn them around if you see this happening so the other side of each pawl engages the cup. I think Norm's idea is a good one to turn to if that doesn't work.
A utility I recently built has the problem but not as severe as yours.
Ahh, if only victa had kept producing the thumblatch catcher series, they would be in better shape today!
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