Mountfield SP51 self drive lawnmower clutch issue

[Michael Ryall]

I purchased this mower in June this year and it works fine except the operation of the clutch. when the clutch is engaged it engages fully straight away without a gradual take up with a huge clonk. The only way to use it without a violent start is to push it and when it is in motion to engage the clutch. Also when the clutch is not engaged and the mower is being pushed or pulled there are random clonks which sound as though they may be damaging over time. Does anyone have experience of this mower and is this normal?

 

[Burnerman]

If you bought the machine new, its still under warranty.
However if you want to do some investigations yourself, here goes!
The clutch cable is connected directly to the rear axle gearbox and a simple lever either engages or disengages the drive. The gearbox doesn’t have any serviceable parts inside.
Remove each rear wheel, one at a time. You’ll see a large gear wheel within the tyre, and a small steel gear attached to the end of the axle. Remove the circlip that holds the small gear in place, pull the gear away and look for a pin that engages the gear to the axle. Note carefully its shape - it must go back the same way! Grease everything in there after cleaning all of the dirt away and reassemble.
Do the same with the other wheel.
At the same time, check the condition of the drive belt that connects the engine to the axle.....you’ll need to tip the machine back on its handles for access.
John

 

[Michael Ryall]

Thanks John, That is most helpful