Usage:
All current Caterpillar engines can be line bored using the 1P4000 Line Boring Tool Group. The 1100, 3100 and 3208 Service Manuals contain line boring instructions for those engines. Centering rings are available for both original and oversize main bearings. Part numbers and sizes are given on pages 2 and 3. Additional information for non-current engines is given in the back of this instruction.
1 Clean all of the bearing caps and saddles and remove all nicks from pan rail (1). Apply layout bluing to the bearings and caps that are to be bored. Plug oil holes (2) in the block with grease to prevent metal chips from entering the oil passages.
2 The original size centering rings given above are not included in the tool group. Two rings are required for each engine. The dimensions given are the true main bearing bore sizes for each engine, and they are stamped on each ring. The diameter of the ring itself is approximately .0005" (0.0127) less than this dimension.
Centering rings given above are for use in oversize main bearing bores. All of these centering rings are for .025" (0.64) oversize main bearing bores, except the 6V138 Centering Ring. The 6V138 Centering Ring is for use in .010" (0.25) oversize main bearing bores.
3 To initially set the micrometer in the bracket assembly, measure the diameter of any centering ring (3) with an outside micrometer that is known to be accurate, and set micrometer (4) to the exact dimension of the ring. Place the ring on the fixture and push the micrometer until spindle (5) lightly touches the ring, then tighten bolt (6). Back off the micrometer thimble and recheck. Repeat the above steps until the micrometer reading is accurate.
4 Place centering rings (3) on each side of the caps that are being replaced.
5 To bore an end cap, place centering rings (3) in the second and fourth main bearing bores.
6 Place the unbored new caps (7) on the block with the part number on the same side as the originals. Stamp each new cap to correspond with the number stamped on the pan rail. Tighten the cap nuts as specified in the Service Manual. Place the original bearing caps over centering rings (3), but do not tighten the nuts.
7 Oil boring bar (8) and insert it through the centering rings. Tighten the caps to a torque of 10-20 lb. ft. (14-25) minimum while spinning the bar to check for binding. The centering rings must be seated securely in the bearing saddles after tightening.
8 Bearing assembly (9) and bridge (10) are used when the centering rings do not provide sufficient support for the boring bar; place bearing assembly (9) on the bar, adjust the bearing by tightening bolt (11) until the bar begins to bind, then back off until the bar spins easily.
9 When boring an end cap, place a bridge on the opposite end of the block. When boring center caps on a long block use a bridge on both ends.
10 Use bridge extensions (12) with bridge (10) for the 6.25" bore V-engines.
11 To install bridge (10), loosen the bolt and rotate the bridge 45° to slip over pin (13). Position the bridge with the thicker portion down, nearest the boring bar. Loosen bolt (14).
12 Install two dial indicators (A), with magnetic bases (B), in the location shown. [Contact point of one dial indicator to be on the side of bar (8), and the contact point of the other dial indicator to be on the top of bar (8).]
13 With bolts (14), (15) and (16) loose, adjust the dial indicators to zero, while spinning bar (8). Tighten bolts (15) finger tight. Tighten bolt (16) lightly, then tighten bolt (14). Tighten bolts (15), then tighten bolt (16). Loosen, then tighten bolt (16). Spin bar (8) and observe the dial indicators. Both dial indicators must read zero while the bar is spinning. If the dial indicators do not read zero while the bar is spinning, do the adjustment procedure again.
14 Bolt torsion bar assembly (17) loosely to the block, opposite the end from which the boring bar will be driven. When used on the rear of a 6.25" bore V-engine block, install bolt (18) on the opposite side of the torsion bar bracket.
15 Install feed assembly (19) into the boring bar and tighten setscrew (20). Slide the feed assembly onto the torsion bar and tighten bolt (21). Tighten bolt (18) finger tight. The boring bar must slide in and out easily after these tightening operations. Tighten thumbscrew (22).
16 Place tool holder (23) or (24) on the micrometer bracket assembly. Align the marks on the shaft and the holder. Tighten the holder bolts. Place the tool bit in the holder and set the micrometer to approximately .070" (1,778) less than the finish bore diameter. Turn the micrometer arm so the tip of the bit touches the center of the micrometer spindle. CAUTION: Do not sweep the micrometer spindle across the carbide cutter. Adjust the bit by pushing it lightly with rod (25). Use .025" (0,635) maximum rough cuts on the diameter, and no larger than .010" (0,254) finish cuts.
17 Wipe the boring bar and the tool holder clean. Place the tool holder on the bar, with the bit facing the direction of rotation. Assemble the small tool holder (23) by placing the lower half over the bolts, then slide sideways into the slot and tighten the bolts. Slip the halves of the larger holder (24) together and tighten the bolts.
18 Place adapter (26) into the boring bar and tighten setscrew (27). Slide the bar until the tool is approximately .12" (3,0) from the bearing. Compare the cutter tip with the bore surface while turning the bar by hand, to insure that the setting is correct. CAUTION: Do not start the boring operation until the setting is found to be correct. Always double check to make sure the cutter tip is set at the proper dimension.
19 Set the feed mechanism into feed by turning lever (28) up (direction of arrow).
20 Oil the centering rings and the bearing assemblies. Do not use lubricant on the cutter. Use a one-half inch electric drill with universal joint (29) to feed the tool through the bearing cap. Drive the tool from either the boring bar end or the feed assembly as shown.
21 The bluing applied to the main bearings indicates the condition of the bore at the correct bore size. If the bluing shows an out of round condition, check the largest diameter (indicated by remaining bluing) in relation to the smallest diameter (indicated by lack of bluing). The difference of the two must not exceed .0005" (0,0127).
22 If the bluing indicates a step in the joint face, measure the diameter at the step in relation to the smallest diameter. A step of .0005" (0,0127) on one or both sides is permitted. A maximum of .0010" (0,0254) over the nominal finish bore diameter is permitted if within the limits prescribed above. The 1P3537 Dial Bore Gauging Group can be used for checking bore diameters.
Care And Maintenance Of The 1P4000 Line Boring Tool Group
The 1P4000 Line Boring Tool Group requires cleaning and lubrication to obtain precision performance. Wipe all parts clean after use and coat with a thin layer of lightweight oil to prevent rust or corrosion during storage. Do not drop or damage the centering rings or any part of the tool group, as this may cause difficulty in obtaining true finish bore.
1 Remove snap ring (1) and bracket (2) from the micrometer bracket assembly. Clean preservative from all parts and oil lightly with clean oil. Install bracket (2) and snap ring (1). Adjust bolt (3) until the bracket becomes tight on the shaft, then loosen the bolt until the bracket moves with a slight drag.
2 The line bore feed assembly must always be completely filled with oil to prevent chatter or erratic feed. To fill the reservoir, place the cylinder in a level position, remove screws (4) and fill completely with clean SAE 20 non-detergent oil.
NOTE: The feed assembly is guaranteed against defective material or workmanship. For warranty or repairs, return to Porta-Tool, Inc., 812 Barstow Avenue, Clovis, California 93612.
Main Bearing Bore Size In Blocks Of Non-Current Engines
NOTE: CENTERING RINGS CAN BE MADE FROM CAST IRON STOCK AS SHOWN. MAKE THE OUTSIDE DIAMETER OF THE RING .0005" ± .0003" (0,013 ± 0,008) LESS THAN THE MAIN BEARING BORE SIZE. THE OUTSIDE DIAMETER MUST BE CONCENTRIC WITH THE INSIDE DIAMETER WITHIN .0005" (0,013).