TRANSMISSION HARNESS ASSEMBLY 1903785 - Caterpillar

3500 Family EnginesIntroduction
(1) 4C8753 Extended ColletThe 4C8753 Extended Collet (1) is designed for use with the 8T1000 Electronic Position Indicator Group, or a dial type indicator, to increase the accuracy of the fuel setting adjustment for all 3500 Family Engines. Use the 4C8753 Extended Collet instead of the 5P4814 Collet for the fuel setting adjustment procedure for all 3500 Family Engines.Use of the 4C8753 Extended Collet prevents side loading of the probe shaft by the fuel stop lever in the governor. This side loading can cause fuel setting errors, and breakage of the contact point on the indicator.Carefully follow the procedures given in this publication, to ensure correct operation of the 4C8753 Extended Collet. Correct operation of the collet is necessary to obtain accurate results when performing the fuel setting adjustment for 3500 Family Engines.Do not perform any procedure, outlined in this publication, or order any parts until you read and understand the information contained within.Reference: Service Manual.Operational Check for the 4C8753 Extended Collet
If the probe shaft and contact point extension are not straight, they can drag in the tube of the extended collet and cause binding that will result in inaccurate readings. Before using the 4C8753 Extended Collet on an engine, do the operational check procedure that follows.
(1) 4C8753 Extended Collet. (2) 5P7263 Indicator Contact Point. (3) 8T1002 Probe.1. Thread 5P7263 Indicator Contact Point (2) [76.2 mm (3.00") long] into the end of 8T1002 Probe (3) (part of 8T100 Electronic Position Indicator Group), or dial indicator shaft, until it is finger tight.2. Examine the threaded end of the 5P7263 Indicator Contact Point (2) to make sure it is seated against the end of the probe shaft, or the indicator shaft. If the indicator contact point will not tighten enough so it is against the end of the 8T1002 Probe shaft, refer to the topic entitled Correcting the Cause of a Sticking Contact Point in this publication.3. Slide 4C8753 Extended Collet (1) over 5P7263 Indicator Contact Point (2) and the probe shaft or indicator shaft. Tighten the nut on the extended collet to hold it in position on the stem.4. Before using the tools on the engine, assemble the parts together as shown and check to make sure the contact point will move freely and does not stick or bind inside the extended collet.5. Press on the end of the contact point so it will go IN as far as possible, then slowly release it. The contact point should come OUT, all the way, without stopping. It should not be necessary for the contact point to be pulled out because of binding or sticking.If the contact point sticks when using a dial indicator, try another dial indicator. If the contact point sticks when using a 8T1002 Probe, refer to the topic entitled Correcting the Cause of a Sticking Contact Point in this publication.Correcting the Cause of a Sticking Contact Point
If the 8T1002 Probe shaft is sticking in the 4C8753 Extended Collet, it may be because of the