79401 Mercury SCREW

The information supplied in this service letter may not be valid after the termination date of this program. Do not perform the work outlined in this Service Letter after the termination date without first contacting your Caterpillar product analyst.
This Program can be administered either before or after a failure. In either case the decision whether to apply the Program is made by the dealer. When reporting the repair, use "PS8305" as the Part Number and "7755" as the Group Number. If administered before failure, use "56" as the Warranty Claim Description Code and use "T" as the SIMS Description Code. If administered after failure, use "96" as the Warranty Claim Description Code and use "Z" as the SIMS Description Code.
This Program does NOT apply to engines that were reworked previously as a result of calling the Injector Call Center.
This Revised Service Letter replaces the June 2, 1995 Service Letter. Changes have been made to the Affected Product.
Termination Date
December 31, 1995Problem
The tip of the fuel injector assembly may fail on certain 3176B Truck Engines.
Affected Product
Model & Identification Number
3176B (9CK629, 9CK632, 9CK634-636, 9CK639, 9CK644-646, 9CK649, 9CK650, 9CK652, 9CK671, 9CK680, 9CK681, 9CK683, 9CK748, 9CK751, 9CK788, 9CK789, 9CK806, 9CK807, 9CK813, 9CK837, 9CK843, 9CK847, 9CK848, 9CK977, 9CK979, 9CK1029, 9CK1049, 9CK1070, 9CK1086, 9CK1095, 9CK1096, 9CK1154, 9CK1168, 9CK1185, 9CK1222, 9CK1249, 9CK1293, 9CK1325, 9CK1336, 9CK1343, 9CK1347, 9CK1350, 9CK1381, 9CK1395, 9CK1403, 9CK1463, 9CK1530, 9CK1531, 9CK1561, 9CK1676, 9CK1707, 9CK1722, 9CK1766, 9CK1776, 9CK1797, 9CK1823, 9CK1860, 9CK1881, 9CK1883, 9CK2016, 9CK2017, 9CK2041, 9CK2060, 9CK2145, 9CK2190, 9CK2240, 9CK2242, 9CK2244, 9CK2251, 9CK2301, 9CK2328, 9CK2336, 9CK2354, 9CK2424, 9CK2460, 9CK2472, 9CK2495, 9CK2504, 9CK2509, 9CK2519, 9CK2587, 9CK2613, 9CK2621, 9CK2623, 9CK2673, 9CK2676, 9CK2692, 9CK2695, 9CK2702, 9CK2815, 9CK2817, 9CK2826, 9CK2852, 9CK2888, 9CK2912, 9CK2933, 9CK2943, 9CK2953, 9CK2974, 9CK2983, 9CK2987, 9CK2989, 9CK2993, 9CK2994, 9CK3005, 9CK3007, 9CK3045, 9CK3050, 9CK3071, 9CK3085, 9CK3086, 9CK3088, 9CK3093, 9CK3101, 9CK3103-3106, 9CK3108, 9CK3110, 9CK3111, 9CK3137, 9CK3141, 9CK3162, 9CK3180, 9CK3189, 9CK3197, 9CK3204, 9CK3257, 9CK3266, 9CK3280, 9CK3284, 9CK3287-3289, 9CK3296, 9CK3303, 9CK3322, 9CK3328, 9CK3329, 9CK3335, 9CK3384, 9CK3402, 9CK3462, 9CK3472, 9CK3477, 9CK3509, 9CK3536, 9CK3537, 9CK3543, 9CK3565, 9CK3575, 9CK3595, 9CK3607, 9CK3638, 9CK3645, 9CK3652, 9CK3676, 9CK3691, 9CK3725, 9CK3727, 9CK3739, 9CK3741, 9CK3752, 9CK3759, 9CK3770, 9CK3792, 9CK3797-3799, 9CK3815, 9CK3816, 9CK3819, 9CK3823, 9CK3846, 9CK3861, 9CK3863, 9CK3864, 9CK3868, 9CK3871, 9CK3873, 9CK3878, 9CK3905, 9CK3907, 9CK3910, 9CK3913, 9CK3955, 9CK3956, 9CK3961, 9CK3962, 9CK3964, 9CK3974, 9CK3975, 9CK3977, 9CK3989, 9CK4053, 9CK4055, 9CK4068, 9CK4075, 9CK4083, 9CK4085, 9CK4087, 9CK4097, 9CK4100, 9CK4102, 9CK4104, 9CK4113, 9CK4117, 9CK4142, 9CK4172, 9CK4189, 9CK4229, 9CK4245, 9CK4291, 9CK4295, 9CK4311, 9CK4313, 9CK4345, 9CK4348, 9CK4384, 9CK4399, 9CK4406, 9CK4410, 9CK4415, 9CK4416, 9CK4441, 9CK4442, 9CK4467, 9CK4476, 9CK4482, 9CK4504, 9CK4528, 9CK4529, 9CK4544, 9CK4546, 9CK4549, 9CK4554, 9CK4565, 9CK4570, 9CK4584, 9CK4590, 9CK4595, 9CK4616, 9CK4641, 9CK4652, 9CK4658, 9CK4659, 9CK4666-4668, 9CK4676, 9CK4706, 9CK4708, 9CK4712, 9CK4715, 9CK4722, 9CK4732, 9CK4741, 9CK4745, 9CK4748, 9CK4771, 9CK4793, 9CK4798, 9CK4802, 9CK4805, 9CK4816, 9CK4820, 9CK4824, 9CK4844, 9CK4845, 9CK4851, 9CK4853, 9CK4870, 9CK4879, 9CK4882, 9CK4887, 9CK4889, 9CK4892, 9CK4898, 9CK4901, 9CK4903-4905, 9CK4912, 9CK4914, 9CK4916, 9CK4935, 9CK4947, 9CK4949, 9CK4951, 9CK4963, 9CK4965, 9CK5003, 9CK5004, 9CK5024, 9CK5036, 9CK5037, 9CK5041, 9CK5044, 9CK5048, 9CK5063, 9CK5067, 9CK5070, 9CK5072, 9CK5085, 9CK5090, 9CK5091, 9CK5106, 9CK5114, 9CK5115, 9CK5117, 9CK5118, 9CK5131, 9CK5136, 9CK5138, 9CK5140, 9CK5148, 9CK5153, 9CK5173, 9CK5176, 9CK5177, 9CK5179, 9CK5230, 9CK5232, 9CK5233, 9CK5235-5238, 9CK5246, 9CK5248, 9CK5249, 9CK5254, 9CK5271, 9CK5306, 9CK5316, 9CK5331, 9CK5334, 9CK5350, 9CK5351, 9CK5353, 9CK5357, 9CK5365, 9CK5366, 9CK5375, 9CK5378, 9CK5388, 9CK5390, 9CK5392, 9CK5394, 9CK5395, 9CK5398, 9CK5405, 9CK5407, 9CK5415, 9CK5422, 9CK5434, 9CK5436, 9CK5446-5448, 9CK5457, 9CK5490-5492, 9CK5494, 9CK5496, 9CK5498-5500, 9CK5516, 9CK5534, 9CK5537, 9CK5539, 9CK5582, 9CK5585, 9CK5593, 9CK5604, 9CK5618, 9CK5623, 9CK5624, 9CK5647, 9CK5670, 9CK5676, 9CK5687, 9CK5695, 9CK5705, 9CK5725, 9CK5738, 9CK5746, 9CK5753, 9CK5757, 9CK5759, 9CK5769, 9CK5770, 9CK5771, 9CK5775, 9CK5779, 9CK5783, 9CK5794, 9CK5796, 9CK5798, 9CK5803, 9CK5804, 9CK5813, 9CK5821, 9CK5822, 9CK5831, 9CK5835, 9CK5843, 9CK5857, 9CK5874, 9CK5902, 9CK5906, 9CK5913, 9CK5915, 9CK5922, 9CK5925, 9CK5927, 9CK5938, 9CK5956, 9CK5959, 9CK5970, 9CK5974, 9CK5988, 9CK5991-5993, 9CK5997, 9CK6006, 9CK6014, 9CK6019, 9CK6035, 9CK6038, 9CK6039, 9CK6048, 9CK6057, 9CK6075, 9CK6077, 9CK6090, 9CK6110, 9CK6111, 9CK6124, 9CK6126, 9CK6135, 9CK6136, 9CK6156, 9CK6159, 9CK6161, 9CK6163, 9CK6172, 9CK6174, 9CK6180, 9CK6194, 9CK6213, 9CK6218, 9CK6219, 9CK6221, 9CK6222, 9CK6224, 9CK6231, 9CK6250, 9CK6253, 9CK6254, 9CK6256, 9CK6259, 9CK6272, 9CK6278, 9CK6280, 9CK6298, 9CK6305, 9CK6319, 9CK6331, 9CK6332, 9CK6364, 9CK6367, 9CK6371, 9CK6380, 9CK6385, 9CK6388, 9CK6391, 9CK6400, 9CK6402, 9CK6404, 9CK6405, 9CK6407, 9CK6413, 9CK6418, 9CK6422, 9CK6425, 9CK6430, 9CK6434, 9CK6445, 9CK6454, 9CK6468, 9CK6473, 9CK6478, 9CK6480, 9CK6518, 9CK6525, 9CK6535, 9CK6559, 9CK6564-6566, 9CK6571, 9CK6574, 9CK6576, 9CK6580, 9CK6586, 9CK6596, 9CK6601, 9CK6610, 9CK6615, 9CK6628, 9CK6635, 9CK6648, 9CK6667, 9CK6678, 9CK6681, 9CK6683, 9CK6685, 9CK6686, 9CK6688, 9CK6690, 9CK6692-6694, 9CK6696, 9CK6698, 9CK6704, 9CK6711, 9CK6713, 9CK6738, 9CK6754, 9CK6759, 9CK6775, 9CK6781, 9CK6806, 9CK6820, 9CK6823, 9CK6825, 9CK6848, 9CK6856, 9CK6859, 9CK6865, 9CK6867, 9CK6876, 9CK6877, 9CK6896, 9CK6903, 9CK6905, 9CK6914, 9CK6923, 9CK6924, 9CK6927, 9CK6957, 9CK6968, 9CK6971, 9CK6977, 9CK6979, 9CK6981, 9CK7008, 9CK7010, 9CK7020, 9CK7022, 9CK7029, 9CK7031, 9CK7061, 9CK7075, 9CK7077, 9CK7078, 9CK7084, 9CK7095, 9CK7099, 9CK7101, 9CK7110, 9CK7114, 9CK7120, 9CK7126, 9CK7127, 9CK7138, 9CK7143, 9CK7145-7147, 9CK7153, 9CK7216, 9CK7262, 9CK7264, 9CK7341, 9CK7390, 9CK7392, 9CK7394, 9CK7396, 9CK7411, 9CK7435, 9CK7437, 9CK7469, 9CK7483, 9CK7538, 9CK7570, 9CK7571, 9CK7573)
Parts Needed
6 - 0R4526 Injector Gp. (For 275 HP Engines)or
6 - 0R4527 Injector Gp. (For 300 and 325 HP Engines)or
6 - 0R4528 Injector Gp. (For 342, 350, 365 and 335/365MT HP Engines)6 - 9X7317 Seal (Tip O-Ring)6 - 9X7557 Seal (Upper O-Ring)6 - 9X7722 Seal (Lower O-Ring)Action Required
See attached rework procedure.
Service Claim Allowances
Filing Claims
Before Failure Repair
File a claim against PS8305 and include all parts and labor required as part of this program.
After Failure Repair
If the failure involved a cracked or split injector nozzle, the failure can be claimed under PS8305. File one claim against PS8305 and include all parts and labor required to make the complete repair. Explain the reason for any additional parts and/or labor in the claim story.
Parts Disposition
Handle the parts in accordance with your Warranty Bulletin on warranty parts handling.
Attach.(1-Rework Procedure)Rework Procedure
1. Check for prior completion of this program by:A. Checking SIMS for PS8163 or PS8305.B. Checking the engine block for the letters "GS" stamped on the block.C. Checking for a "PS8163" label on the valve cover.If there is any indication these programs have already been performed, no further action is necessary.If there is any doubt, call Caterpillar at (309) 578-8590.
2. If there is no indication that the program has already been performed, remove the necessary air piping, air cleaners, valve covers, Jake Brakes, and rocker arm assemblies. Remove the lower plug at the rear of the fuel manifold and drain the fuel from the cylinder head and manifold. Reinstall the plug.3.