PAGE 34 — JTNSW20-24HTCSL SERIES RIDE-ON TROWEL • OPERATION MANUAL — REV. #1 (3/24/16)
MAINTENANCE
Checking Trowel Arm Straightness
Trowel arms can be damaged by rough handling, (such
as dropping the trowel on the pad), or by striking exposed
plumbing, forms, or rebar while in operation. A bent trowel
arm will not allow the trowel to operate in a smooth fluid
rotation. If bent trowel arms are suspect, check for flatness
as follows, refer to Figure 35 and Figure 36.
Figure 35. Trowel Arm
1. Use a thick steel plate, granite slab or any surface
which is true and flat, to check each trowel arm for
flatness. Use the flat top and bottom sides for reference.
2. Check the top and bottom sides of the trowel arm. A feeler
gauge of .004" (0.10 mm) should not pass between the
flat of the trowel arm and the test surface along its length
on the test surface. (Figure 36).
Figure 36. Checking Trowel Arm Flatness
3. Next, check the clearance between the round shaft and
the test surface as either the top or bottom flat section
of the arm rests on the test surface. Rotate the arm to
the opposite flat section and check the clearance of the
round shaft. Use a feeler gauge of .005" (0.127 mm).
Each section should have the same clearance between
the round of the trowel arm shaft and the test surface.
4. If the trowel arm is found to be uneven or bent, replace
the trowel arm.
TROWEL ARM
ROUND SHAFT
SECTION
TROWEL LEVER
MOUNTING SLOT
ROLL PIN
HOLE
TROWEL ARM
ROUNDED
SHAFT SECTION
BLADE
ATTACHMENT
BOLT HOLE
FLAT OF
TROWEL ARM
(TOP/BOTTOM)
Trowel
Arm
Flat Test
Surface
FEELER GAUGE
(.004 in. / 0.10 mm)
FEELER GAUGE
(.005 in. / 0.127 mm)
Trowel Arm Adjustment
1. Locate the trowel arm adjustment tool (Figure 37)
P/N 9177.
Figure 37. Trowel Arm Adjustment Tool
(Side View)
2. Ensure the fixture arm is in the proper setting (up or down)
for your trowel arm rotation as shown in Figure 38.
Figure 38. Trowel Arm Adjustment Setup
3. Shown in Figure 39 is the adjustment fixture with a
trowel arm inserted. As each trowel arm is locked into
the fixture, the arm bolt is adjusted to where it contacts
a stop on the fixture. This will consistently adjust all of
the trowel arms, keeping the finisher as flat and evenly
pitched as possible.
Adjustment
Bolt
“Distance”
Locking
Nut
Fixture
Arm
NOTICE
Arms with
clock-wise
blade rotation use the fixture arm
in the UP position (A in Figure 38). Arms with
counter
clock-wise
blade rotation use the fixture with the fixture
arm in the DOWN position. (B in Figure 38).
A
B
