GUIDE 3T5947 - Caterpillar

Test 5
Check for Excessive Starter Current.
Connect a current probe (DC) around either of the large wires that are connected to the PRELUB magnetic switch. Use a 155-5176 Current Probe .
Turn the key to the CRANK position. Observe the current after the starter motor has run for more than 2 seconds in PRELUB Mode. Note: Do not use "Peak Hold" or "Record Mode" on the DMM for this test.Expected Result: The DMM reads at least 300A while the key is in the CRANK position. The DMM should read at least 400A for 12V systems.Results:
Yes - The starter current is excessive. Go to Step 2.
No - Service batteries and charge batteries as needed. Check PRELUB wiring connections from the starter solenoid to the PRELUB magnetic switch for looseness, corrosion, or hot spots. Make sure that the ground connections are good. Repair the problems with the circuit and retest the system.
Check for Oil Leakage.Check for oil inside the starter motor. Expected Result: Oil is present inside the starter motor.Results:
Yes - Oil is present could be accompanied by a PRELUB pump lid gasket failure, which is an indication of a PRELUB Check Valve failure, or excessive restrictions in the Pressure hose of the PRELUB system. Go to Step 3.
No - Replace the starter motor and retest the system.
Pinpoint Oil Leak.The oil could be entering from the starter nose housing or the oil could be entering from the PRELUB pump. Remove the starter and inspect the nose housing.Results:
Oil appears to be coming from the nose housing. Replace the starter and retest the system.
Oil appears to be coming from the PRELUB pump. Replace the starter. Replace the PRELUB check valve. Repair any restrictions in the pressure hose. Retest the system.Test 6
Test 6 can be made much quicker and easier by making a PRELUB bypass connector. To make the PRELUB bypass connector, perform the following procedure. Procedure to Build a PRELUB Bypass Connector
Table 3
Parts Needed    
Part Number     Description     Quantity    
102-8805     Receptacle Kit     1    
9W-0852     Connector Pin     1    
N/A     14 AWG wire    
152.4 mm (6 inch)    
Using the proper crimp tool, install 9W-0852 Connector Pins on each end of the 14 AWG wire.
Insert one end of the 14 AWG wire (with 9W-0852 Connector Pin installed) into Location 3 of the 102-8805 Receptacle Kit . Insert the remaining end of the 14 AWG wire (with 9W-0852 Connector Pin installed) into Location 5 of the 102-8805 Receptacle Kit .
The PRELUB bypass connector can now be plugged into the PRELUB wiring harness in place of the timer. This will restore normal operation of the starter with no PRELUB function. If the starter now works normally (less the PRELUB mode and delay), replace the PRELUB timer. If the starter still chatters or does not engage, begin with Step 2 below.The batteries must be fully charged and the battery cables must be clean and tight before continuing.
Test For PRELUB Timer Fault.Note: The PRELUB Mode