Checking Starter Pinion Gap; Starter No-Load Test - Toro Workman 3000 Series Service Manual

Checking Starter Pinion Gap

1. Install 12 volt battery between the "S" terminal and
the starter body. The pinion should protrude and stop.
IMPORTANT: Never apply battery voltage to the
starter for longer than 10 seconds.
2. Lightly push the pinion back and measure the return
stroke (called pinion gap).
3. If the pinion gap is not within standard range of 0.5 -
2.0 mm (0.02 - 0.08 in.), adjust it by increasing or
decreasing the number of packings on the magnetic
switch. The gap is decreased as the number of packings
increases.

Starter No-Load Test

1. Connect a 12 volt battery, ammeter and voltmeter to
the starter as shown.
2. When terminals "S" and "B" are connected the pinion
should protrude and the starter should run smoothly.
Terminal voltage: 11.5V
Current: 100 A
Speed: 3000 rpm
No-Load Test Results
Low speed and high current draw:
- High friction (faulty bearings, bent armature shaft).
- Shorted armature.
- Grounded armature or fields.
Failure to operate with high current draw:
- Direct ground in terminals or fields.
- "Frozen" bearings.
Failure to operate with no current draw:
- Open field circuit.
Low speed and low current draw:
- Open armature coils - check commutator for badly
burned bars after disassembly.
Liquid Cooled Diesel Engine
High speed and high current draw:
- Poor contact between brushes and commutator
(broken brush springs, worn brushes, high insulation
between commutator bars).
- High internal resistance (poor connections, dam­
aged leads, dirty commutator or open field circuit).
- Shorted fields.
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Figure 29
Figure 30
Workman 3300-D/4300-D