There's another point that suggests the engine being changed, the engine alignment looks out and this is why the clutch is grabbing and letting go thus spinning the cutter reel when it shouldn't. One must remember that the machine was sent to the tip for a reason and not just for fun. Now it's up to someone with a bit of knowledge and not on an hourly clock charging full rates to sort it out and gain the benefits.
I need some close up shots of the clutch housing at various angles with the clutch engaged and then disengaged to assess what's the issue but I'm sure that engine has been off and not correctly aligned upon re-installation.
Another knocking scenario may well be as simple as a not rock tight fitment of the clutch to the PTO shaft. Check to see if those two set screws are locked up tight as if this is a case of free play then a knocking sound will be evident at idle but not at high speed. Just while I think of it do a check of how concentric the clutch revolves around while pulling the rope starter at a slow speed, eg. not at the same rate you would pull it to start. If it wobbles left and right as it revolves then you have an issue there. Do this step prior to checking those screws and their tightness.
The last port of call will be a big end knock in the crankshaft of the engine that again is evident at low revs.
Check these points out and please get back to me with your findings.
Cheers,
BB.
Last edited by Bonnar_Bloke; 25/02/17 04:57 PM. Reason: Added extra text
