Pilot Production CAT Multifunction Speed Sensor Bracket

Technical Support Subject Pilot Production ©CAT Multifunction Speed Sensor Bracket Version Document Department Revision Details Revised by Tech Engineering Implemented A EXT-MF-008 Tech Document Release BDJ 18 Aug2021 N/A NC 19Aug2021 Knowledge Base:kb.vmacair.com Page 1 of 2 Email: tech@vmacair.com Web: www.vmacair.com Technical Support: 1(888)241-2289 Toll Free:1(800)738-8622 Fax: 1(877)740-3201 SYSTEM OR PARTS AFFECTED • Some Pilot Production CAT C1.1 diesel engine powered Multifunction Power Systems. (System Identification numbers will begin with PPCATMF…) • Part No. 1201042 BRACKET, SENSOR OVERVIEW Some early Pilot Production CAT powered Multifunction Power Systems have a speed sensor bracket, (Figure 1) which may be subject to distortion due to vibration, causing the air gap between the speed sensor and the engine flywheel change. If air gap goes out of spec, the system will shut down and display box will display “Engine Under Speed” error message. Figure 1 CHECK SPEED SENSOR BRACKET AND AIR GAP Measure the air gap between the speed sensor and the teeth on the flywheel (Figure 2). The specification is 0.020 in minimum to 0.031 in maximum (0.025 in nominal). If the speed sensor air gap is outside of specifications, measure the thickness of the speed sensor bracket. The early production bracket was made from 16 gauge sheet steel which measures 0.0598 in (1/16 in is the closest fractional thickness) and a new more robust part is available. Speed sensor bracketTechnical Support Subject Pilot Production ©CAT Multifunction Speed Sensor Bracket Version Document Department Revision Details Revised by Tech Engineering Implemented A EXT-MF-008 Tech Document Release BDJ 18 Aug2021 N/A NC 19Aug2021 Knowledge Base:kb.vmacair.com Page 2 of 2 Email: tech@vmacair.com Web: www.vmacair.com Technical Support: 1(888)241-2289 Toll Free:1(800)738-8622 Fax: 1(877)740-3201 Figure 2 REPLACEMENT OF SPEED SENSOR BRACKET AND AIR GAP ADJUSTMENT If the sensor bracket material is 16 gauge and the air gap is outside of specification, replacement of the speed sensor bracket is required to prevent a reoccurrence of the problem. The current production speed sensor bracket is made from 12 gauge sheet steel which measures 0.1046 in (7/64 is the closest fractional thickness). Order and install a new Part No. 1201042 BRACKET, SENSOR, and set the air gap to 0.025 in by loosening the fasteners holding the bracket in place and moving it to achieve the correct gap. Air gap 0.020 in min 0.025 in nominal 0.031 in max