HT25 - MAINTENANCE 89 Visually check digging chains for wear on rollers and sidebars. Check pins and bushing wear by measuring distance between chain pins and comparing it with a new chain. 2. Turn digging chain until connector pin is on top of boom. Replace sprockets when a new chain is installed. 1. Start unit, following directions in OPERATION . om1744x om1752x 5. Secure chain by clamping links on either side of connector pin with chain jaws. Squeeze jaws to reduce pressure on connector pin. 6. Loop cable through links nearest connector pin. Chain Replacement 3. Lower boom to ground. p To remove chain: 4. Stop engine. TRENCHER