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page 40 — MQS36H SeRIeS WaLK-BeHIND TROWeL • OpeRaTION aND paRTS MaNUaL — Rev. #0 (03/08/12)
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Troubleshooting (Walk-Behind Trowel)
Symptom
possible problem
Solution
Engine running rough or not at all.
Engine ON/OFF Switch in "OFF" position
or malfunctioning?
Make sure that the Engine ON/OFF Switch is ON
or replace switch if necessary.
Centrifugal ON/OFF Switch in "OFF"
position or malfunctioning?
Place centrifugal stop switch in "ON" position.
Check wiring. Replace switch if necessary.
Fuel?
Look at the fuel system. Make sure there is fuel
being supplied to the engine. Check to ensure that
the fuel fi lter is not clogged.
Ignition?
Check to ensure that the ignition switch has power
and is functioning correctly.
Loose wire connections
Check wiring. Replace or repair as necessary.
Bad contacts in ON/OFF switch?
Replace ON/OFF switch.
Trowel bounces, rolls concrete, or makes
uneven swirls in concrete.
Blades?
Make certain blades are in good condition, not
excessively worn. Finish blades should measure
no less than 2"" (50mm) from the blade bar to
the trailing edge, combo blades should measure
no less that 3.5"" (89mm). Trailing edge of blade
should be straight and parallel to the blade bar.
Pitch adjustment?
Check that all blades are set at the same
pitch angle as measured at the spider. A fi eld
adjustment tool is available for height adjustment
of the trowel arms. (Contact Parts Dept.)
Bent trowel arms?
Check the spider assembly for bent trowel arms.
If one of the arms is even slightly bent, replace it
immediately.
Spider?
Check fi t of arms in spider. This can be done by
moving the trowel arms up and down. If there is
more than 1/8 inch (3.2 mm) of travel at the tip of
the arm, the spider and arms should be replaced.
Thrust collar?
Check the fl atness of the thrust collar by rotating
it on the spider. If it varies by more than 0.02 inch
(0.5 mm) replace the thrust collar.
Thrust collar bushing?
Check the thrust collar by rocking it on the spider.
If it can tilt more than 3/32 inch (2.4 mm) - as
measured at the thrust collar O.D., replace the
thrust collar.
Thrust bearing worn?
Check the thrust bearing to see that it is spinning
freely. Replace if necessary.