1. Take a measuring calliper A.
2. Use the table below to find the respective Hi (initial height) of the front idler B that corresponds to the code of your undercarriage, and note it down for use in subsequent measurements.
3. Bearing in mind that this check should be carried out before 250 hours (three-monthly), proceed with measurement.
4. The acceptable wear limit corresponds to 75% of the initial value Hi: therefore, when the corresponding value is reached replace all the catenary front idlers B; checks on other abrasion zones will still need to be carried out.