I just picked up a decent used 1990 Komatsu PC-40-6 excavator to use on the farm, SN:13942. Runs OK for its age and seams to have plenty of power for its size. It has a 37.8 Hp 3 cylinder diesel engine. Unit weight is around 5 ton. One question is how large of a bucket could I put on it before I start causing issues? The bucket that is on it now is approximant 15" deep, 24" long and 22" wide, I estimate it to be around 0.15 Cu Yard? Not going to dig in hard clay or rock. Most of the time I will be moving soft mud from bottom of old farm pond. Any input form anyone will be great. Also, anyone have a OPERATION & MAINTENANCE MANUAL that could be had?
My Yanmar Vio 35 (7700 lds) uses a 32 inch wide 5 cubic foot clean up bucket and slings heaped buckets of muck out of my waterhole at full reach with no issues. I would guess your machine would handle a 6 to 7 cubic foot clean up bucket.
My mid 90's PC40 R8 is running a 48 inch mud bucket. Gets a bit "tippy" when full of wet muck at full extension, possibly 36 inches would be a better choice?