Volvo Articulated Hauler (42114) doesn't operate the bucket I cannot get the rams to lift or lower the tipper body I suspect its something to do with the clutch mechanism since all the shafts and gears rotate freely until the clutch is connected. The white clutch mechanism seems very stiff to turn. Is this normal for this clutch in a new kit?
I can get the truck to drive and steer ok but it won't operate the lifting rams.
Two steps below taken from first instruction booklet for 42114 set. Since one end of clutch is locked it basically tells, that under normal conditions, clutch should not be spinning at all. Clutch is used as a safety feature within the build, when something get stuck, not to cause further damage to gears or human flesh. So in this case it should only begin spinning if the rest of gear train is having issues.

I'm not entirely sure what could be causing your issue of bed not operating, but I suspect one other tricky place could be the reason. Please pay attention to location of 20 tooth bevel gear for each side (highlighted in blue) in pictures below. One of these needs to be on top on one side and on the bottom on the other. If placed in same direction, one side will pull while the other will be pushing.