How do I adjust track tension on a mini excavator and know if it is too tight or too loose?

Expert Answer

Mini excavator track tension is usually checked by measuring the sag in the track span between the carrier roller and front idler, but the correct amount depends on the machine size and the maker’s manual. As a general guide, a small mini excavator often has around 10-15 mm of movement, while larger minis need more sag, not less.

If the track is too tight, it can increase drive load, wear the rollers and sprocket faster, and put extra strain on the idler adjuster seals. If it is too loose, the track can walk off in turns or soft ground, especially when the undercarriage is packed with mud or stones. Clean the undercarriage first, then check tension on level ground with the machine raised as specified by the manual.

To adjust it, locate the grease fitting in the front adjuster. Add grease to tighten; release grease carefully to reduce tension. Make small changes, move the machine forward and recheck, because the setting can shift once the track seats itself.

A simple rule: the track should have some sag, run straight, and not slap, bind, or derail in normal travel. For VANROCK undercarriage parts, track chains, rollers, idlers, sprockets, rubber tracks, and track hardware are supplied through our dealer network, with pricing quoted on request. If your machine is a Caterpillar, Komatsu, or another OEM brand, VANROCK is an independent manufacturer and is not affiliated with that OEM.

Answered by VANROCK specialists · Published 10/7/2026