DOWEL-HOLLOW 1047006 - Caterpillar

D353 Engines With Spacer Plate BlockThe 8N6938 Insert, .0628"-.0636" (1.60-1.62) thick, and the 8N6939 Insert, .1278"-1286" (3.246-3.266) thick, are available to make a repair for those engines in the above list, that have erosion (wear caused by heat, plus exhaust gas and coolant leakage around the liner seal) at the top of the cylinder liner seat area. These stainless steel inserts fit in the counterbore that must be cut in the cylinder block. After installation, the top of the insert will be far enough above the top surface of the cylinder block to give the necessary liner projection. After the inserts are installed, it is not necessary to machine them.Tools Needed
*Also needed - 1.00" (25.4) long contact point with 0-80 threads.**Parts of 5P1618 Tool Arrangement***New tools****This tool or a similar tool is optional.*New tool used for 8N6938 Insert**New tool used for 8N6939 InsertProcedure For Accuracy Check Of 5P4175 Counterboring Tool Group
Since the 8N6938 and 8N6939 Inserts are precision made, the counterbore that they fit must be parallel to the top of the cylinder block within .001" (0.025). The 5P4175 Counterboring Tool Group must then be checked for accuracy, to be sure it will cut within this .001" (0.025) tolerance, unless it is already known that the tool group has this type of accuracy. At specific intervals, use the procedure that follows to check tool group accuracy. The accuracy check procedure does not especially have to be done on a D353 spacer plate cylinder block. It can be done on any cylinder block that has the top deck (top surface) ground smooth and flat, or, one that is in very good condition. If the top deck is not smooth and flat, the result will be depth measurements that are not correct. All adjustments and/or settings in the procedure must be made according to the bore size of the cylinder block that is used for the accuracy check. (1) Assemble tool holder (1) to boring tool. Make sure the tool holder slot is down and both the pilot on the boring tool and the pilot on the tool holder are clean. Install the washer and nut. Tighten nut (2) to 50 5 lb. ft. (70 7) torque. Check the bottom surface of base adapter (3), and remove any nicks or burrs. (2) With the boring tool in the horizontal position, remove plug (5) and check the oil level in the hydraulic feed unit. Fill the unit with SAE10W, 20W, or 30W oil. Install plug (5). Loosen knob (4) to release the feed control valve and move tool holder (1) in and out several times. Remove plug (5) and again check the oil level. Fill with oil if necessary and install plug (5). Tighten knob (4). If the oil level is low, the tool may not cut smoothly. (3) Put the boring tool in position on the cylinder block. Release feed control valve (4) so the tool holder will go down, into the pilot bore of the cylinder liner.