is it a major job to replace the handbrake cable on this machine. Handbrake doesn’t work and I’m presuming this is the most likely cause.
Welcome to HEF @Wayne1963 A handbrake cable is not really a "major" job on a backhoe - However, the if the clevis pins are seized they can be difficult. There are two different parkbrake set-ups on 580E, so, depending on the one you have, there is quite a difference. Early models have the cable going to a cross-shaft on top of the transaxle. If this is the type you have, there maybe other issues if it has not been used for a while. Later models use a disc on the front of the transaxle. Regardless of the type you have, you need to disconnect the cable from any actuating lever & then see if the cable is seized or if the problem is with the operating mechanisms.
Thanks for the help