I’m at a loss on this one and looking for some help. Been around equipment for 30 years and never had this issue. Komatsu PC170-10 with no coupler, removed both bucket pins and the bucket still won’t budge. Hooked a chain to my 145 excavator and it drug the 145 towards it. On every other machine I have had you pull the pins and bucket falls right off. Machine has 5800 hours on it so it shouldn’t be that tight. Is there a trick to these Komatsu’s that I’m missing?
Sounds like a bushing might have walked out.
Maybe a photo of the ends of the pins might help. Does the machine have a thumb?