MQ Multiquip HDA SERIES, Operation, Service, & Parts

PAGE 40 — HDA SERIES WALK-BEHIND TROWEL • OPERATION MANUAL — REV. #0 (12/1/17) 

MAINTENANCE

Trowel Arm Adjustment

The easiest and most consistent way to adjust a trowel arm 

is with the trowel arm adjustment tool (P/N 1817).
Once locked into the adjustment tool, each trowel arm 

bolt is adjusted until 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.
Perform the following procedure to adjust trowel arms using 

the trowel arm adjustment tool.
1.  Unscrew the locking bolts on the adjustment tool and 

place a trowel arm (with lever attached) into the fixture 

channel as shown in Figure 65. A thin shim may be 

needed to cover the blade holes on the trowel arm.

Figure 65. Trowel Arm Adjustment

2.  Make sure the fixture arm is in the 

UP position 

(Figure 66).

Figure 66. Fixture Arm Position (UP)

3.  Align the trowel arm adjustment bolt with the fixture 

adjustment bolt (Figure 65).

TROWEL ARM

(PLACED IN

FIXTURE CHANNEL)

TROWEL

ARM

LEVER

FIXTURE

ADJUSTMENT

BOLT

FIXTURE

ARM

DISTANCE = .010 in.

TROWEL ARM

ADJUSTMENT TOOL

LOCKING

BOLTS

SHIM

TROWEL ARM

LOCKING NUT

TROWEL ARM

ADJUSTMENT BOLT

.010

"

UP

DOWN

CORRECT

INCORRECT

4.  Tighten the locking bolts (Figure 65) to secure the 

trowel arm in place.

5.  Loosen the locking nut on the trowel arm lever, then 

turn the trowel arm adjusting bolt until it barely touches 

(.010") the fixture adjustment bolt.

6.  Tighten the trowel arm locking nut to lock the trowel 

arm lever in place.

7.  Loosen the locking bolts on the adjustment tool, and 

remove the trowel arm.

8.  Repeat steps 1–7 for the remaining trowel arms.

REASSEMBLY

1.  Examine the entire spider assembly. Clean the wear 

plates and thrust collar. Use a wire brush to remove 

any concrete or rust buildup. Replace any spider 

components that are damaged or out-of-round.

2.  Inspect the bronze trowel arm bushing, and clean it if 

necessary. Replace the bushing if it is damaged, worn, 

or out-of-round.

3.  Reinstall the trowel arm bushing onto the trowel arm.
4.  Repeat steps 2–3 for each trowel arm.
5.  Make sure the spring tensioner is in the correct position 

to exert tension on the trowel arm.

6.  Insert all trowel arms with levers (and bronze bushings 

already installed) into the spider plate. Align the grease 

holes on the bushings with the grease hole fittings on 

the spider plate.

7.  Lock the trowel arms in place by tightening the Zerk 

grease fitting hex head bolts and jam nuts.

8.  Reinstall the blades onto the trowel arms.
9.  Reinstall the stabilizer ring onto the spider assembly.
10.  Reinstall the lower wear plate, thrust collar, and 

wear ring onto the spider shaft in the reverse order 

of disassembly. 

MAKE SURE there is little or no 

lateral movement between the thrust collar and the 

spider shaft.

11.  Carefully lift the upper trowel/gearbox assembly, align 

it with the keyway on the spider shaft, and insert it into 

the spider assembly.