CHECK PINION ENGAGEMENT.
1.) Engage the pinion into the ring gear. This can be done by either:
Using a tool to pull the pinion out of the starter OR Connecting 12 VDC to the “Switch” terminal only. (DO NOT connect battery cable to “BAT” terminal on the starter
solenoid). This engages the solenoid and pinion but does not spin the starter. CAUTION: Do not leave the solenoid engaged like this for more than 30 seconds at a
time as the solenoid will overheat.
2.) Insert a wire gauge to check for proper backlash between the ring gear and starter pinion (see Figure 2). There should be a 0.020” to 0.025” clearance measured
from the flank of a starter pinion tooth to the flank of a ring gear tooth. Check clearance at least three places on the ring gear. If the clearance CHECK PINION CLEARANCE.
There should be 0.060”~0.140” clearance from the face of ring gear to the front face of the starter pinion. Check in at least six locations on the ring gear (see Figure 1).
If not in spec, verify that the ring gear is properly mounted and does not have excessive runout. The included shims can be installed between the starter mounting block
and the starter’s center support to increase this distance. (See box “Installation Instructions for Internal shim”)
CHECK PINION ENGAGEMENT.
1.) Engage the pinion into the ring gear. This can be done by either:
Using a tool to pull the pinion out of the starter OR Connecting 12 VDC to the “Switch” terminal only. (DO NOT connect battery cable to
“BAT” terminal on the starter solenoid). This engages the solenoid and pinion but does not spin the starter. CAUTION: Do not leave
the solenoid engaged like this for more than 30 seconds at a time as the solenoid will overheat.
2.) Insert a wire gauge to check for proper backlash between the ring gear and starter pinion (see Figure 3). There should be a 0.020”
to 0.025” clearance measured from the flank of a starter pinion tooth to the flank of a ring gear tooth. Check clearance at least three
places on the ring gear. If the clearance is too small, add one shim at a time between the starter and engine block to bring it into speci-
fications. In many installs, no shims are necessary.
3.) PLEASE NOTE: After releasing the solenoid, the pinion may stay engaged in the ring gear until the engine is started. This is normal for gear reduction starters and
does NOT require shimming to correct.
ATTACH BATTERY CABLE AND SWITCH WIRE. The switch wire should be capable of handling 50A intermittent and
10A continuous, typically a 12AWG wire. The battery cable must be the proper size for the length of the cable (see
chart). All connections should be clean and tight and terminals should be soldered if possible. The ground cable is
important and the best ground path is direct to the engine block. With steel frame vehicles the ground path can be to
the frame. This ground cable should be the same size as the starter positive cable. Also, a ground strap should be
installed from the frame to the engine. If the original solenoid had a connection to the “R” terminal (ballast resistor
bypass), this wire can usually be eliminated. (See explanation below.)
CONNECT THE BATTERY.
OPERATE THE STARTER–it should operate quietly. The cables and connectors themselves should be checked for voltage drop with a voltmeter. To check any wire or cable
for voltage drop, connect one side of the voltmeter to one end of the cable and the other side of the voltmeter to the other end. OPERATE THE CIRCUIT and simultane-
ously measure the volt drop. It should be 0.5VDC or less. A high voltage drop indicates a bad connector or an undersized cable. The ground circuit can be checked in
the same manner.
Measure input voltage by connecting the positive probe of a voltmeter to the “MOTOR” terminal of the solenoid and connecting the negative to the starter housing. This
should be 9.6V minimum while cranking.
COMMON QUESTIONS
1. Why does the engine seem to crank slowly? Although this condition can be caused by several things, the most common cause is excessively low input voltage. The input voltage to the
starter must be 9.6V volts or higher. Low voltage during cranking can be caused by undersized starter cables, high resistance or defective batteries, high resistance battery disconnect
switches, or poor connectors.
2. What do I do with the wire that connected to the ‘R’ terminal on the original starter? In early original wiring harness the ‘R’ circuit was a ballast resistor bypass. This terminal is ‘no
connection’ when the starter is at rest and is +12VDC while cranking. This circuit provided +12VDC to the ignition coil during cranking for easier engine starting. Cars that do not have a
ballast resistor (i.e. HEI, MSD or other aftermarket ignition systems) should not need this connection. In most cases this wire can be eliminated. If the engine has no ignition during crank-
ing, then the wiring of the coil is going to require an ‘R’ terminal signal. To accomplish this use the optional “R Terminal Diode Kit” P/N 600. Some Powermaster replacement solenoids
are available with an ‘R’ terminal. Ask your dealer.
ADDITIONAL NOTES ON INSTALLATION
1. A note about ring gears. It is important for long starter life that the ring gear be round and true. Check the ring gear in at least six places verifying that the clearance for the starter is
the same in all locations. If not remove the ring gear and make sure the mounting surface of the crankshaft is clean and free of paint buildup or rust. Reinstall the ring gear and properly
torque the mounting bolts. If this does not correct the problem, replace the ring gear.
2. Disconnect switches in race cars and other off road vehicles. The switch used for a battery disconnect is very important. All of the starter current will go across this switch during
cranking which, depending on the starter, can be as high as 700A! After the engine is running, all of the current from the alternator will be running across this switch. Therefore make
sure that the switch that is being used can handle these amounts of current. Switches are rated in intermittent amps and continuous amps. The intermittent rating should match or exceed
the amount the starter will pull and the continuous rating should match or exceed the amount the alternator can produce. Using a switch that is too small will result in voltage loss and
possible switch failure.
Distance
aWG
3’
21000
5’ 7’ 10’ +10’
4
FIGURE 3
CAUTION: Never operate astarter more thaN 30 secoNds at atime without allowiNg time to cool
at least two miNutes. overcraNkiNg will damage the starter.
WIRE GAUGE CHART
INS097 Revised 8/16/10
