Hayter Harrier 48 479 series blade brake

HI Folks.
This is the Blade Brake system on a Hayter Harrier 48 479 series mower.
Customer said about a noise except when the BB was engaged.
After the video I started the mower up but didn't video it as it was late, but there was a lot less noise when the BB was idling.
I'll know how it sounds' next week when he uses it again.

[@TGMForum]

Looked like the top pulley half had broken away from it's hub, hence the brake arm shaking forwards and backwards. There was a recall for the early ones for this. When it got really loose the top pulley half would break up and eject itself from the mower. Also the hole where the cable spring attaches would wear through and become unattached. There's a shorts vid on my channel on a 48 where it did just that.

[@themowerman]

Good video mate

[@DugatDizzyLizzys]

Thank you.

[@user-of6gv4db1r]

Hi I’ve got a Hayter 48 pro 2019 and a vibration when starting I’ve checked what you did in the video and seems fine any ideas? Thanks

[@DugatDizzyLizzys]

Hi
I had one in that the engine bolts were loose that made the engine move when starting and engaging the blade brake.
If it's when you use the blade brake, check the blades balanced, and everything is secure and correctly fitted.
Hope that helps.

[@user-of6gv4db1r]

Hi thanks for your reply. It’s when it’s reving as soon as the blade is engaged it is smooth??

[@DugatDizzyLizzys]

@user-of6gv4db1r when the BB is engaged, it grips the 2 discs to drive the blades.
Same thing on this mower is happening. As they were loose they make a vibration until the BB is engaged because of wear.
If you say it looks ok, then is the grub screw tight and the discs close together as where the grub screw tightens down on, can wear and allow the discs to move about.
Also check the belt tensioner and other bits along the belts path.
TBH, it's easier when I can see it, than to help online.
I hope this is helpful 😁