Jammed cutting height adjuster on my HRB 425c

[Poplarlincs]

Quite suddenly, well today actually, I needed to adjust the cutting height on my mower. Try as I may, the lever will not move upwards to lower the blade. Downwards and back to 3rd notch OK, anything further up it will not go.

Any ideas, guys & gals?

Trevor

 

[mechanic mark]

Take the weight off wheels by placing boards, wood, underneath deck. Spray down area with penetrating oil & let soak, I would do this on all adjusters. Every month during mowing season use lubricating oil on all moving parts including cables.