Usage:
NOTE: 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.
NOTE: 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 "PS4588" as Part Number, "7755" as Group Number, and "96" as Description Code.
NOTE: Some of the Affected Product fall into more than one group. Do all applicable portions of this Service Letter at the same time.
Termination Date
July 31, 1992Problem
Pistons may scuff in the liners of certain 3508, 3512, and 3516 Engines due to improper combustion especially during cold starts. The new governor control reduces the fuel used during start-up. The new water temperature regulators and the change to the regulator housing will help maintain cooling system temperatures both during engine operation and while heating with jacket water heaters. The jacket water heaters or ether starting aid systems will provide improved starting with smooth combustion. All of these items will help prevent piston scuffing.
NOTE: The use of a starting aid (either jacket water heaters or an ether starting aid system is recommended on any 3508, 3512, or 3516 Engine which is operated in air temperatures of 13°C (50°F) or lower.
Affected Product
Group 1
Model & Identification Number
3508 (23Z1535-3018)
3512 (24Z1736-3155)
3516 (25Z916-1866)
Group 2
Model & Identification Number
3508 (23Z1535-3130)
3512 (24Z1736-3265)
3516 (25Z916-1937)
Group 3
Model & Identification Number
3508 (23Z1535-3164)
3512 (24Z1736-3325)
3516 (25Z916-1942)
Group 4
Model & Identification Number
3508 (23Z1535-3475)
2512 (24Z1736-3690)
3516 (25Z916-2141)
Parts Needed
Group 1
Group 2
- 1 - 7E5253 Governor Control Group
Group 3
Group 4
If installing jacket water heaters:
All Group 4 Engines
Plus the following for 3508 Engines
- 2 - 1S0724 Clip
- 2 - 7K3377 Pipe
- 2 - 0S1619 Bolt
- 4 - 5M2894 Washer
- 2 - 9S8752 Nut
- 1 - 5N1649 Hose As.
- 1 - 6H8297 Elbow
- 1 - 6F0496 Tee
- 1 - 3M7045 Plug
- 2 - 5P0598 Clamp
- 1 - 5N5988 Hose As.
- 2 - 6B9081 Bushing
- 1 - 4P4774 Bracket A.
- 2 - 2H3745 Bolt
- 2 - 5P8250 Washer
- 2 - 8V2636 Spacer
- 1 - 2R7712 Coupling
- 1 - 7C1707 Bracket
- 1 - 0S1571 Bolt
- 2 - 9F7716 Clip
- 1 - 5N1649 Hose As.
- 2 - 5P8250 Washer
- 2 - 9S1368 Bolt
- 2 - 1S2303 Spacer
- 2 - 5P0598 Clamp
- 1 - 6F0496 Tee
- 1 - 3M7045 Plug
- 1 - 2B0858 Plug
- 1 - 2R7712 Coupling
- 1 - 8N0855 Hose As.
- 1 - 043935 Elbow
- 1 - 8N8550 Elbow
- 1 - 7N4945 Gasket
- 3 - 0S1594 Bolt
- 1 - 5B4855 Bushing
- 1 - 6H8297 Elbow
- 2 - 8S5107 Spacer
- 2 - 0L1329 Bolt
- 2 - 5P8245 Washer
- 1 - 1L4031 Tee
- 1 - 6B9081 Bushing
- 1 - 5F6371 Connector
- 2 - 7K3377 Pipe
7E6249 Heater or 7E6248 Heater plus the following for 3512 Engines:
- 2 - 1S0724 Clip
- 2 - 7K3377 Pipe
- 2 - 0S1619 Bolt
- 4 - 5M2894 Washer
- 2 - 9S8752 Nut
- 1 - 3N7223 Hose As.
- 1 - 6H8297 Elbow
- 1 - 6F0496 Tee
- 1 - 3M7045 Plug
- 2 - 5P0598 Clamp
- 1 - 5N5988 Hose As.
- 2 - 6B9081 Bushing
- 1 - 4P4774 Bracket As.
- 2 - 2H3745 Bolt
- 2 - 5P8250 Washer
- 2 - 8V2636 Spacer
- 1 - 2R7712 Coupling
- 1 - 7C1707 Bracket
- 1 - 0S1571 Bolt
- 4 - 9F7716 Clip
- 1 - 3N7223 Hose As.
- 2 - 5P8250 Washer
- 2 - 9S1368 Bolt
- 2 - 1S2303 Spacer
- 2 - 5P0598 Clamp
- 1 - 6F0496 Tee
- 1 - 3M7045 Plug
- 1 - 2B0858 Plug
- 1 - 2R7712 Coupling
- 1 - 8N0855 Hose As.
- 1 - 043935 Elbow
- 1 - 8N8550 Elbow
- 1 - 7N4945 Gasket
- 3 - 0S1594 Bolt
- 1 - 5B4855 Bushing
- 1 - 6H8297 Elbow
- 2 - 8S5107 Spacer
- 4 - 0L1329 Bolt
- 4 - 5P8245 Washer
- 1 - 1L4031 Tee
- 1 - 6B9081 Bushing
- 1 - 5F6371 Connector
- 2 - 7K3377 Pipe
7E6249 Heater or 7E6248 Heater plus the following for 3516 Engines:
- 3 - 1S0724 Clip
- 3 - 7K3377 Pipe
- 3 - 0S1619 Bolt
- 6 - 5M2894 Washer
- 3 - 9S8752 Nut
- 1 - 3N4911 Hose As.
- 1 - 6H8297 Elbow
- 1 - 6F0496 Tee
- 1 - 3M7045 Plug
- 2 - 5P0598 Clamp
- 1 - 5N5988 Hose As
- 2 - 6B9081 Bushing
- 2 - 5P0598 Clamp
- 1 - 6F0496 Tee
- 1 - 3M7045 Plug
- 1 - 2B0858 Plug
- 1 - 2R7712 Coupling
- 1 - 8N0855 Hose As.
- 1 - 043935 Elbow
- 1 - 8N8550 Elbow
- 1 - 7N4945 Gasket
- 1 - 4P4774 Bracket As.
- 2 - 2H3745 Bolt
- 2 - 5P8250 Washer
- 2 - 8V2636 Spacer
- 1 - 2R7712 Coupling
- 1 - 7C1707 Bracket
- 1 - 0S1571 Bolt
- 6 - 9F7716 Clip
- 1 - 3N4911 Hose As.
- 2 - 5P8250 Washer
- 2 - 9S1368 Bolt
- 2 - 1S2303 Spacer
- 3 - 0S1594 Bolt
- 1 - 5B4855 Bushing
- 1 - 6H8297 Elbow
- 2 - 8S5107 Spacer
- 6 - 0L1329 Bolt
- 6 - 5P8245 Washer
- 1 - 1L4031 Tee
- 1 - 6B9081 Bushing
- 1 - 5F6371 Connector
- 3 - 7K3377 Pipe
If access to an electrical power source for the jacket water heaters is not available, you may install an ether starting aid system.
If installing an ether starting aid:
- 1 - 7X1078 Nozzle As. *
- 1 - 3B6768 Bushing *
- 1 - 1N3416 Tube
- 4 - 6V2686 Clip
- 3 - 0S0509 Bolt
- 11 - 5M2894 Washer
- 4 - 0L2070 Bolt
- 6 - 7B8167 Bolt
- 12 - 5P0537 Washer
- 6 - 9S8750 Nut
- 5 - 5P9085 Clip
- 12 - 7S1197 Screw
- 24 - 6V9499 Washer
- 12 - 4B2043 Nut
- 6 - 5N6645 Shockmount
- 1 - 9X3207 Control Group*
- 2 - 7C0348 Bracket
- 4 - 0S1618 Bolt
- 20 - 9M1974 Washer
- 1 - 5P0598 Clamp*
- 1 - 9X9584 Resistor Assembly*
- 2 - 7E8961 Bracket
- 8 - 4B3388 Bolt
- 8 - 5S0003 Nut
- 1 - 9X7137 Valve Assembly*
- 4 - 0S1594 Bolt
- 2 - 7C0347 Bracket
- 2 - 7C0346 Bracket Assembly
- 1 - 6B1628 Bushing
- 1 - 7X5988 Switch Assembly
- 1 - 7X1062 Cylinder Assembly *
- 2 - 3T3048 Clip Assembly
- 2 - 3T3045 Clip Assembly
- 1 - 7X1063 Fitting Assembly *
- 1 - 4P2570 Harness Assembly **
- 1 - 8C9812 Switch
- 1 - 4P2569 Harness Assembly ***
- 1 - 3B6768 Bushing *
*3516 requires 2
**3516 only
***3508 and 3512 only
Action Required
Before or After Failure
NOTE: Reference Service Magazine May 13, 1991
Group 1
Install low leakage water temperature regulators. See the article on Page 14 of the June 25, 1990 Service Magazine (Page 6 of the July 1990 Engine News).
Group 2
Change 2301 Governor Control to 2301A Governor Control. See Special Instructions SEHS9188 "Installation of 7E5253 Governor Control Assembly."
NOTE: Fuel Limit/Ramp Time must be set during installation of 2301A Governor Control. "Maximum" fuel setting and "minimum" ramp settings must be set to prevent over fueling at startup. Se the fuel limit initially to minimum and the ramp limit initially to maximum acceptable and then adjust as needed.
Group 3
The hole in the bottom of the top regulator housing that allows coolant from the top housing to drain to the bottom housing when the engine coolant is drained needs to be plugged.
To plug the hole, remove the top regulator housing and tap the 10.5 mm hole (shown in the illustration) to accept a 7F9504 Plug (" standard pipe thread). When installing the 7F9504 Plug in the tapped hole, make sure top of the plug is flush with (or slightly below) the surface of the housing.
9Y9121 Housing (Upper Regulator Housing)
Group 4
Install 6kW Jacket Water Heaters. See Special Instructions SEHS9340 "Jacket Water Heater Installation Procedures."
- OR -
If an electrical power source for jacket water heaters is not available, install an ether starting aid system. See article on Page 8 of the December 17, 1990 Service Magazine (Page 6 of the December 1990 Engine News).
After Failure - All Groups
Repair all damage resulting from failure due to a piston scuffing/seizure; install all new pistons; and do the applicable steps for Groups 1 through 4 listed above. No labor will be allowed for installing update parts in Groups 1-4.
Service Claim Allowances
Parts Disposition
Handle the parts in accordance with your Warranty Bulletin on warranty parts handling.