Troubleshooting - Grillo HWT 375 Uso Y Mantenimiento

TROUBLESHOOTING

The following is a list of small problems which may arise during use of the TRIMMER bush cutter, which
the customer is able to set right unaided:
1. The engine does not start: proceeding in the order given below, check:
– That the fuel tank is at least half full;
– That the fuel tap is turned on (if the engine has this feature);
– That the choke is engaged (if the engine is cold);
– That fuel is reaching the carburettor;
– That the vent hole on the tank cap is not blocked;
– That the mesh filter on the carburettor intake is clean (if present);
– That the carburettor nozzles are clean. To check them, unscrew them and clean them with an air jet
if dirty;
– That the plug is providing a spark. To check this, remove the plug, reconnect it to the power supply
cable, rest the metal part on an electrical ground and turn the engine pulley as if to start it. If no spark
is seen between the two electrodes, try checking the plug cable connections and if power is still not
received, replace the plug. If the new plug still fails to work, the problem is in the electrical system,
and you should contact your nearest service centre or a specialist workshop.
2. When the lever is engaged the string cup does not turn:
– Adjust the string register (fig. 1 N° 4);
– Make sure that the belt has not come out of its seat on the pulley.
3. The machine does not cut well:
– Make sure that the cutting diameter is at least 300 mm; if it is less than this, replace the strings with
new ones;
– The belt may be slipping: in this case, the clutch wire register can be adjusted or the engine can be
moved back a few millimetres by undoing the three screws on the engine connection flange.
4. The cup keeps turning even when the lever is disengaged;
– Check that the blade brake is working; in this case, undo the M5 nut on the end of the tie-rod (fig. 9)
until the pad is touching the surfaces of the driven pulley groove.
– Make sure that material has not accumulated on the brake pad, preventing it from operating;
– The belt may be too tight: undo the clutch wire register (fig. 1 N° 4). If this is not enough, undo the 3
screws on the engine flange and move it forward a few millimetres.
For HWT 600 WD only.
When the travel lever is engaged, the machine does not move or moves with difficulty:
– Adjust the belt stretcher wire register (fig. 2 N° 10).
LONG LAY-OFFS
If the machine is to be out of use for a lengthy period, the following precautions should be adopted:
– Drain off the fuel;
– Drain off the engine oil (4-stroke engine);
– Lubricate the cylinder by pouring in one spoonful of AGIP SAE 30 oil through the spark-plug hole and
turning the engine over a few times;
– Clean the engine and the bush-cutter thoroughly;
– To prevent problems in the carburettor, use the preservative additive for unleaded petrol.
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