BAR 1446117 - Caterpillar

Governor Calibration Bench Adjustment Of Torque Limiter
CH55 Tractor Only
This abbreviated procedure is intended only as an alternate means to check and adjust the CH55 Torque Limiter adjustment of the Governor "off-engine" on a Governor Calibration Bench, when a PTO Dynamometer is not available. This procedure and the Specifications listed apply only to the CH55 governor (113-5914 or 134-9898 Governors) and should not be used when complete governor bench calibration is needed, such as after a major governor repair or overhaul.Use TMI for complete Governor Specifications.
1. Remove the CH55 engine governor from the engine. Use Service Manual procedures for governor removal and installation. Be sure to keep the governor clevis pin (linkage pin) with the governor, as the pin is needed during bench testing. The RPM's referred to in this procedure are governor test bench rpms, and NOT engine rpm.
2. Install governor on Governor Calibration bench, and prepare it for bench test. Refer to the Governor Service Manual, Form SENR6454 (October 1994). This manual includes instructions for obtaining Governor Specifications from TMI. Always use the TMI to determine the complete governor test specifications for the particular GOVGRP part number and change level of the governor.The "change level" is shown on the governor information plate just after the governor part number. For example,GOV GRP113 591403.In this example it is a 1135914 Governor, with change level 03. TMI provides governor specifications for each change level of a governor, if the change level is specified.
3. Pressurize and hold the Fuel Ratio Control to 20-30 PSI so that FRC cannot restrict governor output during this test. Use a pressure-regulated air supply.4. Remove Governor Seal and Lockwire.5. Remove small Hexagonal Cover over the Torque Limiter adjustment screw (Illustration 1).6. Loosen Torque Limiter locknut, and back out (turn CCW) the adjustment screw at least two (2) full turns, before testing the governor.- Be sure to follow Governor Service Manual procedures when testing, such as lowering governor rpm slowly to the desired test rpm from at least 100 rpm above thetest rpm. The Torque Limiter Adj. is a new feature used only on certain applications, and is not yet described in the Governor Service Manual. However, the procedures for adjusting bench rpm, making the adjustment, and rechecking it are similar to those forthe Load Stop adjustment. The Torque Limiter must be checked with the Fuel Ratio Control (FRC) pressurized to 20-30 psi, so the FRC does not restrict governor output.
7. Run governor on bench. Increase test bench rpm to approximately 1500 rpm. Be sure FRC remains pressurized.- Do not loosen or make changes to the High Idle (throttle stop) or Low Idle adjustment screws during this abbreviated test procedure.
- Be sure the initial set-up on the governor bench is correct, per the Governor Service Manual, and that the correct calibration pin (1U7316) is being used.The governor bench calibration pin is not the same pin that is used for checking Static Fuel Setting on the engine.
- Do not attempt to check or re-adjust the "Load