Masport 4 in 1 mower - how to remove chipper blade?

[Kev_A]

Hi,
I have a Masport 625ex - Chip, Mulch, Catch rotary mower. I am trying to remove the chipping blade as I believe the four bolts that hold it in place have sheared due to a collision with a rock.

After removing the quad cut blade carrier (similar to the image below) by removing the central bolt and spring washer, I cannot see how to remove the rest of the assembly from the base of the crankshaft.

The part that is highlighted below, needs to be removed from the crankshaft as it sits below the chipper blade, but I can't see how it comes apart.

[MitchellMc]

Welcome to the Bunnings Workshop community @Kev_A. It's brilliant to have you join us, and many thanks for your question about removing a chipping blade.

To remove the carrier from the crankshaft, you would typically need a gear puller. Due to the keyway, I suspect it would be too hard to do by hand. The carrier pulls directly off the shaft.

Ensure the sparkplug is removed from the lawn mower during this type of maintenance to prevent accidental ignition.

Please let me know if you have any questions.

Mitchell
 

[Kev_A]

Thanks for the prompt response Mitchell. I will pick one up today.

2 questions:

1. Does it have a separate piece slotted in the keyway that I need to be looking for when I remove it?

2. Is there any reason why I can't put it back together  without refitting the chipper blade (have never used it and not sure I can be bothered extracting the sheared bolts)

[MitchellMc]

Hi @Kev_A,

There is a key in the keyway that you'll need to look out for. It's a small piece of metal.

The chipper blade can be removed, and the quad cut can be re-installed. However, having spoken to Masport technical, I'd encourage you to take it to a service centre to be assessed. The chipping blade is attached with four bolts and it's unlikely that they would have sheared off. That's what the keyway is there for, as it should shear first. If an impact has caused all four bolts to shear, then the mower should be assessed to ensure it is safe to use, and you shouldn't just re-install the quadcut and continue use.

Mitchell

[Kev_A]

Thanks Mitchell, I will check it out. The chipper blade spins freely on the shaft, but the quadcut blades still operate. Once I have removed it from the crankshaft, I will have a better idea of what's happened. Getting it checked in the event the 4 bolts have sheared makes sense. Thanks again.