NH1530 Wobble box

[Salt'n'Pepper]

How much play between the pulley and the knife drive arm should there be?
I have tightened the two grub screws under the pulley which I think is supposed to reduce any play but there seems to be still about over an inch of play,when the knife drive arm changes direction.
The wobble box was making a bit of a banging noise and the knife drive arm was hitting the first finger section,before breaking the bolt that connects the knife and the arm.
Eventually gave up and called in two old senators to finish our 15acre field-did a grand job
Do I need to simply replace the wobble box with another,or could it be reconditioned?

TIA S&P

 

[balerman]

Take it apart and have a look,plenty of time to get a new one if you don’t like what you see.

 

[Salt'n'Pepper]

I have taken it apart,no obvious signs of bearing failure,some wiggle in the two ends that join to the y shaped piece,but seems ok apart from that.
The two grub screws are about 3mm deep into the casing and not sure how much further they can safely go,but are tight at that,but still gives over an inch play between the input and output.I assume that there should be less than that.

 

[Rooney]

Is the taper shaft ok, remember having to replace ours when it took side out of keyway. Gearbox wobblebox replaced eventually checked oil level regularily after that

 

[Salt'n'Pepper]

The taper shaft that connects onto the arm that drives the knife was a little bit scored and the nut holding it on could have been tighter,but I don't think that was the problem,the key and keyway are fine.