Hyundai 35DS-7 Operation Manual page 246

Adjustment
Chain adjustments are important for the following reasons :
Equal loading of chain.
Proper sequencing of mast.
Prevent over-stretching of chains.
Prevent chains from jumping off sheaves if they are too loose.
A A djustment procedure
With mast in its fully collapsed and vertical position, lower the fork to the floor.
Adjust the chain length by loosening or tightening nut on the chain anchor.
After making adjustment on the mast, be sure to tighten the nut.
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