CYLINDER HEAD GP 2014257 - Caterpillar

Caterpillar: Confidential Yellow
SAFETY:MAY 9, 1984 - PI1020 - REPLACE, INSPECT, AND/OR RETIGHTEN CRANKSHAFT COUNTERWEIGHT BOLTS - 3508, 3512, 3516 ENG INES - MAILED WORLDWIDE; SEE84-10-23 SL
  The information supplied in this service letter may not be valid after the termination date of this program.   Do not perform the work outlined in this Service Letter after the termination date without first contacting your Caterpillar product analyst.
REPLACE, INSPECT, AND/OR RETIGHTEN CRANKSHAFT COUNERWEIGHT BOLTS, 3508, 3512, 3516 Engines 1202, PI1020 U-41 A-26 AU-33 B-14 C-38 E-23 O-29 SEE OCTOBER 23, 1984 safety Cross out your copy of the July 8, 1983, Service Letter, PI1007, and add a note referring to this new Safety Service Letter. PI1007 is replaced by this new PI1020. Engines already modified with the former bolts used to do PI1007 do not need remodified. Attach the Fel-Pro list to this new Service Letter. Problem Some of the crankshaft counterweight bolts in the above engines can break if the surface of the bolt becomes pitted. A broken counterweight bolt can cause extensive engine damage. New counterweight bolts are now used which will not break if they become pitted. Also, a special lubricant is now used on the bolts when they are installed and tightened to prevent damage to the mating surfaces. Formerly engine oil was used. Affected Engines And New Parts Needed All of the following listed engines are included in this Program. Model Serial Numbers Bolts Needed 3508 Industrial 95Y1-95Y618 18-4W6358 68Z1-68Z676 3508 Marine 96Y1-96Y604, 608 * 69Z1-69Z253 * 3508 Generator 23Z1-23Z472, 474-509, 520 * Set 528 *, 535 *, 544 * 70Z1-70Z552 3512 Industrial 49Y1-49Y357, 359-427 36-4W6358 65Z1-65Z590 3512 Marine 50Y1-50Y488, 490-520 66Z153 3512 Vehicular 51Y1-51Y463, 465-467, 473 3512 Generator 24Z1-24Z433, 435-445, 447-760, 762-767, 773 *, 778 * 67Z1-492 3516 Marine 29Z1-29Z744, 746 *, 747 * 48-4W6358 72Z313 3516 Vehicular 28Z1-28Z595 3516 Generator 25Z1-25Z427 Set. * These engines were listed in the July 8, 1983 Service Letter, PI1007, as needing to have all bolts replaced. Our records show that these engines have not had the bolts replaced. If one or more of these engines are in your territory and did have new bolts installed according to PI1007, then it is not necessary to install new bolts again. Action Requested (Parts Stock Action Not Required) 1. Remove