TM 10-3930-671-24 Battery    service    must    be    done    by trained  personnel.    Battery  acid  can cause severe burns and injury. NOTE To  perform  this  service  procedure,  it is recommended that you first: • truck safely. • Apply    parking    brake    and    block    drive wheels. • Return   all   controls   to   neutral   and   turn ignition   key   OFF,   except   as   otherwise noted. Refer  to  Section  2.    1,  Service  Specifications,  Section 4.3, Engine Tune- Up, and Section 6.1, Electrical System Wiring. Minimum Tools Required • Digital voltmeter. • Volt-ohm meter. • Battery tester. Remove    all    jewelry    (watch,    rings, bracelets,    etc.)    before    working    on electrical systems.  Severe burns can result    from    contact    with    electrical circuits. Always follow the manufacturer’s instructions   for   the   test   instrument being used when making connections   and   tests   on   electrical circuits     or     damage     to     equipment could occur. Starting System Mechanical Checks 1. Check the battery. Be sure that the battery is in good condition and fully charged before attempting to test the starter and     wiring     circuit     for     problems.          It     is recommended that you perform a voltmeter test and a battery load test. 2. Check starter mounting bolts. The  bolts  which  mount  the  starter  motor  to  the flywheel  housing  must  be  kept  tightened  to  the correct torque.  The starter must be held tightly in   the   proper   mounting   position   for   correct engagement with the engine flywheel to prevent damage   to   both   starter   pinion   and   ring   gear teeth, and to provide starter ground circuit. Refer to Section 2.  1, Service Specifications, for starter mounting bolt tightening torque. F-298