Specifications

Section 7: Servicing 37/44
PROBLEM Re-reeling speed is not constant
REMEDY It should be noted that the speedometer installed gives an approximate hose re-reeling rate
reading with a an error of ± 15%. The instrument is calibrated on half the entire length of the
hose. To solve this problem, use a lower gear unit speed (2nd rather than 3rd) with the same
reeling in rate. Then increase the speed of the turbine and use a chronometer to check the
actually running speed. If the problem persists, do the compensation procedure described in the
section on “AUTOMATIC SPEED COMPENSATION”.
PROBLEM After reeling in three-quarters of the hose, the machine stops.
REMEDY Check if the gear unit lever is still engaged (pos 7, photo H). If it is disengaged, this means that
the safety protecting against incorrect hose re-reeling has tripped.
Check if the hose slide unit has clear signs of malfunction (breaks in the chain, shaft screw
worn, etc.).
If everything is fine and the hose is correctly reeled, regulate the safety:
For Model 550: slacken off the clamp halfway along the steel wire and move it 10 mm towards
the rain gun carriage. Tighten the clamp back in this new position.
For Models 570, 580, 590, 600GX, 890, 990 lengthen the wire connecting the probe touch the
hose with lever (pos. 7, photo H).
To do this, use the register on the cable so extend the wire for about 10 mm (be careful you
choose the right cable and not the one that controls the disengage).
For Models 700, 800, 900, Major: bend the end opposite the rubber lever handle (pos 7, photo
H) about 40 mm or adjust with the appropriate register.
If the hose is badly wound (the hose touched the frame at the bottom), do not make the
registrations described above.
Unreel the hose with the tractor for at least 80-150 m and then do a fast re-reel with the by-pass
closed and the gear in 4th.
If this does not solve the problem, contact your nearest RM Technical Assistance Centre.
PROBLEM On Model 550, 560, 570, 580, 590 and 600GX the manual work with the hand pump to lift
up the carriage is extremely difficult.
REMEDY Remove the ballast from the carriage and check to make sure that the stop dog (pos. 2 photo D)
is disengaged when the rain gun carriage is raised or lowered.
PROBLEM On model 700, 800, 900, Major the hydraulic plant cannot raise the machine when it is full
of water. In other words, the wheels do not lower.
REMEDY
Try using a different type of tractor. If the problem persists, change the setting on the relief value
on the hydraulic circuit.
Use a socket wrench to remove the outside cap-head screw while holding the inside screw tight
with a normal wrench. Then use a hex wrench to screw in the regulating screw at least 4 turns.
Replace the cap-screw and try lowering the wheels. If this is not sufficient, repeat the procedure.
PROBLEM The machine leaks from the hole under the turbine casing.
REMEDY The mechanical seal is worn or obstructed.
The working life of the mechanical seal inside the turbine can vary from 2000 to 8000 work
hours depending on the hardness and cleaness of the water (contact RM Technical Assistance
Centre for instructions on how to change the seal).
Note that some leakage through the seal is normal especially during the first working hours (the
two contact surfaces forming the mechanical seal have to adapt to each other).
It is good standard operating practice to take action as soon as you note real leaks since
in this way you will prevent damage to the turbine.