Troubleshooting
91
Pre-stretcher
Hydraulics
Problem
Cause
Solution
Page
Holes in the stretched film
The pre-stretcher rollers are
dirty
> Clean the pre-stretcher roll-
ers
The film tears at the lower edge
The pre-stretchers are set too
low
> Increase the height of the
pre-stretchers
The film slips along the tilted
surface of the bale
The pre-stretchers are set too
high
> Decrease the height of the
pre-stretchers
Problem
Cause
Solution
Page
Oil flow blockage in the quick-
couplings
•
Blocked return coupling
> Change the return coupling
Oil heats up
•
Wrong setting of the valve
block
•
Too high oil flow from the
tractor
•
Check setting of the valve
block
•
Reduce the oil flow to 26 l/
min
•
34
•
34
Spool valve unit faulty
The spool valve does not move
freely
> Move the spool valve back-
wards and forwards a few
times
> Push the plastic cap at the
end of the magnet
Summary of Contents for 7420
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