7 Care and Maintenance
TC29
76
7.9.14 Crawler chains
Checking the crawler-chain tension
• The check has to be carried out on a level
surface.
• Slew the uppercarriage by 90° and lift on one
side until the crawler is free.
• The sag of the crawler between lower roller
and crawler chain (Fig. 65-distance "a") should
equal
approx. 25 – 35 mm (steel crawler chain)
approx. 15 – 20 mm (rubber crawler chain)
Tensioning the crawler chain
• Remove the cover on the right-hand and left-
hand side of the crawler frame. Re-tension the
crawler chain using the hand grease gun via
the grease nipple (65/1).
• Move crawler chain and check the crawler-
chain tension once more.
In the case of new rubber crawler chains,
check the sag on the first day of
operation 2 - 3 times and re-tension if
necessary.
Releasing the crawler chain tension
When releasing the crawler chain
tension, proceed with caution as grease
may drain under pressure.
• In order to release the tension, slowly loosen
the valve (65/2) with the grease nipple, let
grease drain out until the crawler-chain tension
is correct.
• Re-tighten the valve with the grease nipple.
• Remove grease and dispose of in compliance
with regulations.
• Move the crawler chain and check the crawler-
chain tension once more.
Fig. 65-Crawler-chain tension