Engine - HT4100 Service Assemblies
Bulletin No. T 87-13
File in Group 6A
Number 81
Corp. Ref. No. 716101
Date Sept. '86
SUBJECT: HT4100 SERVICE ENGINE ASSEMBLIES
MODELS AFFECTED: ALL 1982-1987 WITH HT4100 ENGINES
This bulletin supersedes T-85-95A which should be destroyed.
The following is a revised list of HT4100 service engine assemblies available from GMWDD to accommodate 1982 through 1987 Cadillacs. These production hot tested assemblies incorporate all of the design refinements and updates released at the time of their manufacture. Some of these updates will affect future service on these engines. Refer specifically to Bulletins T-87-14 and T-87-15. Additional updates will be covered in later bulletins.
MODEL SERVICE ENGINE P/N
1982 Eldorado and Seville ...........................................3634705
1983-84 Eldorado and Seville 1985 Eldorado and Seville (Except Calif.)
1984-85 Eldorado Convertible (All) ..................................3634703
1985 Eldorado and Seville (Calif.) ..................................3634707
1982 De Ville and Brougham ..........................................3634704
1983-84 De Ville and Brougham
1985 Brougham (Except Calif.) .......................................3634702
1985 Brougham (Calif.) ..............................................3634706
1985-86 De Ville and Fleetwood (FWD)
1986 Eldorado and Seville ...........................................3634698
1987 De Ville (FWD), Eldorado and Seville ...........................3634699
1987 Allante (Note: Includes Ignition Distributor)...................3634700
Service engine assemblies include: cylinder block assembly, connecting rods, piston and liner assemblies, crankshaft, crankshaft balancer, camshaft and lifters, cylinder head assemblies including valve trains, camshaft and crankshaft sprockets with chain, front cover, water pump, oil pump, oil pan, intake manifold, oil filter, and instruction sheet.
When installing these service engine assemblies:
1. Transfer Parts
The following components must be transferred to the replacement service engine:
engine vehicle identification plate, exhaust manifolds, throttle body, distributor with thrust washer, EGR valve, generator, power steering pump, vacuum pump (if so equipped), AIR pump, A/C compressor, flexplate, and all brackets, pulleys and belts.
^ When assembly 3634698 is installed in a 1985 FWD "C" chassis or a 1986 FWD "C" chassis before 4252323, the oil filter adapter must also be transferred.
^ When assembly 3634698 or 3634699 is installed in an Eldorado or Seville the thermostat housing must also be transferred.
^ Engine lift brackets in some cases may have to be transferred to accommodate accessory mounting requirements of the vehicle.
2. Special Distributor Gear Note
Before installation of the distributor, the distributor thrust washer must be transferred from the original engine to the service engine and a new distributor gear (10499163) must also be installed. The new distributor gear must be lubricated with prelube (P/N 1052365).
3. Items Ordered Separately
1982-1984 Eldorado and Seville
1052365 Distributor Gear Prelube
10499163 Distributor Gear
412485 EGR Valve Gasket
1624583 Throttle Body Gasket
1630830 Crankcase Breather Hose
1626761 PCV Hose
6487779 PCV Valve
1629941 Throttle Cable Bracket
*489106 Cap-Vacuum Tee
1631153 Vacuum Pump Bracket
2044779 Clip - Evaporator Pipe Attachment
22527475 Screw - Evaporator Pipe Attachment
*1982 Only
1982-1984 RWD De Villes and Broughams
1052365 Distributor Gear Prelube
10499163 Distributor Gear
412485 EGR Valve Gasket
1624583 Throttle Body Gasket
1630830 Crankcase Breather Hose
1626761 PCV Hose
6487779 PCV Valve
1629940 Throttle Cable Bracket
*489106 Cap-Vacuum Tee
*1982 Only
1985 FWD De Villes and Fleetwoods Originally Equipped With Stamped Metal Valve Covers
1052365 Distributor Gear Prelube
10499163 Distributor Gear
412485 EGR Valve Gasket
1620870 EFE Grid Gasket
1630831 Crankcase Breather Hose
9438373 PCV Hose
6487532 PCV Valve
1628916 Vacuum Pump Outlet Pipe
1631225 Power Steering Pump Bracket
1985-1986 All Models Originally Equipped With Cast Valve Covers
1052365 Distributor Gear Prelube
10499163 Distributor Gear
412485 EGR Valve Gasket
1624583 Throttle Body Gasket (Longitudinal Engine)
1620870 EFE Grid Gasket (Transverse Engine)
1987 All Models Except Allante
1052365 Distributor Gear Prelube
10499163 Distributor Gear Prelube
412485 EGR Valve Gasket
1620870 EFE Grid Gasket
1987 Allante
1052365 Distributor Gear Prelube
10499163 Distributor Gear Prelube
1636127 Upper Manifold Gasket
4. Dipstick Considerations
^ Longitudinal service engine assemblies (3634702 through 3634707) are not supplied with a new dipstick. The original parts must be transferred. See chart below for revised applications.
^ P/N's 3634698 and 3634699 are equipped with a dipstick calibrated for 1986 De Villes after 4252323 and 1987 De Villes respectively.
^ If 3634699 is installed in a 1987 Eldorado or Seville, transfer the dipstick from the replaced engine (1640020).
^ If 3634698 is installed in a 1986 Eldorado or Seville transfer the dipstick from the replaced engine (1640020).
^ If 3634698 is installed in a 1985 De Ville or a 1986 De Ville before 4252323 install dipstick 1629282.
The following chart summarizes HT4100 engine oil dipstick revisions for 1982 through 1987 applications.
Application Tube Dipstick
82-83 "C" 1618780 1640021
84-85 "D"
85 "C" & 86 "C" 1636933 1629282
Before 4252323
Application Tube Dipstick
86 "C" After 1636933 1638398
4252323 & 87 "C"
82-85 "E/K" 1618780 1640022
86-87 "E/K" 1636933 1640020
87 "V" 1636933 1638874