YOKE 9U0290 - Caterpillar

SUPPLEMENT: 10/07/91Service Magazine; April 15, 1991; Page 4; "Simplified Battery Testing Procedure SEHS7633-02 And Battery Test Sheet SEHS9326 Available".In COSA, use form G1052 only for testing batteries in accordance with Special Instruction SEHS7633-02. This was announced in the COSA General Letter, CSD No. 12 dated May 15, 1990. DO NOT use form SEHS9326. Paragraph 3 and 4 of the article refer to an Open Circuit Voltage (OCV) of 12.40 as having sufficient charge to use, sell or load test the battery. This is correct providing it is a stabilized voltage. If the OCV was measured shortly after recharging, invariably the reading will be falsely high due to a surface charge on the plates. Remove the surface charge as described in Special Instruction SEHS7633-02 by applying a load of half the cold cranking amperes (cca) rating for 5 seconds. Allow the battery to recover and measure the OCV. If the OCV recovers to 12.40 or more, the battery can be put into use or load tested. If it does not, further charge the battery.
Always use a digital voltmeter for all battery voltage checks. If testing 8 or 6 volt batteries, the equivalent OCV is 8.27 and 6.20 volts, respectively.--------------- END SUPPLEMENT ---------------Reference: Special Instructions: SEHS7633-02, "Battery Test Procedure" and SEHS9326, "Battery Test Sheet". (IRM): PELE0187, BAT 91-4, "Simplified Battery Test Procedure"; PELE0172, BAT 90-7, "New Battery Test Tool Available" PELE0178, BAT 90-9A, "New Battery Load Tester".A new Battery Test Procedure, SEHS7633-02, has been published. The new procedure covers all aspects of testing batteries. It also covers charging and warranty determination.
You can save time and money by using this new, simplified method of testing batteries. Instead of using a hydrometer to measure the specific gravity of the acid in each cell, you simply touch a voltmeter to the battery terminals. The voltmeter reading will tell you the open circuit voltage which indicates state of charge. Any reading of 12.4 volts or more (in a 12 volt battery) means there is sufficient charge to use, sell, or load test. Any reading less than 12.4 means a recharge is needed.
Once the battery is at a sufficient state of charge (12.4 or more), a load test can be performed to determine if the battery is good or bad. Connect the battery to a load tester. Set at 1/2 the cold cranking amp (CCA) rating from the Parts Sales Kit, PEKP9100. After 15 seconds, the voltage should be 9.5 or more (for a 12 volt battery). Any lower reading indicates a bad battery.
Use a digital voltmeter for measuring the battery's state of charge. Analog-type (moving needle) testers are not accurate enough for battery work. A fully charged battery will measure 12.7 volts; 12.4 volts indicates a 75% charge; and 12.0 indicates the battery is almost dead.
Never load test a battery that reads less than 12.4 volts. It will always test bad. When the battery is charged, it may test good.
A Battery Test Sheet, SEHS9326, is now available. It follows the same step-by-step procedure used