Page 777 - 2021 Sierra Catalog

➀18-3668D
18-3667
THERMOSTAT KIT
—CONTAINS—
18-3668
THERMOSTAT KIT Replaces: 807252T4, 807252Q4
—CONTAINS—
Part # Description O.E.#
18-2552 Thermostat Cover Gasket 27-33179-2
18-1977-1
THERMOSTAT HOUSING Replaces: 47441, 47441A1
Fits: 225, GM 260, 228, 898/198, 185R, 898R, 228R, 2GR
18-2553 Thermostat Cover Gasket 27-47510
18-2554 Thermostat Cover Gasket 27-41812 18-3551 Thermostat 59137
Part # Description O.E.#
18-2555 Thermostat Cover Gasket 27-89656-1
18-3555 Thermostat 99155A1
18-7173 O-Ring 25-30224
18-2917 Thermostat Housing Gasket 27-53045-1, 27-33918
18-1989
THERMOSTAT HOUSING Replaces: 8M0061381, 861006A1 Stainless Steel
Use 18-1989K Thermostat Service Kit for replacement parts
18-1994
THERMOSTAT HOUSING Replaces: 87290A4
For: Stainless Steel Version use 18-1989
18-3531
THERMOSTAT HOUSING Replaces: 807074A1, 808064A1, 861188A1
Fits: MCM/MIE GM V-6 & V-8 (305, 350, 454 & 502 cid) engines w/closed cooling systems
18-1910
THERMOSTAT HOUSING KIT Replaces: 47587, 47587A2, 47588, 60372A1, 60372A2, 63908A2, 861493A07, 861493A3
Fits: 3.0L GM 1999-Up, S/N 0L340999-Lower
18-1989K
THERMOSTAT SERVICE KIT Service Kit for 18-1989 Thermostat Housing
THERMOSTAT APPLICATION
18-1508 THERMOSTAT SEAL
Replaces: 25-8071341
Fits: Vazer (2007 & UP), GM V6 & V8 with closed cooling systems (1996 & UP)
Engine/Model
CID/#CYL
Year Range
Beginning Serial #
Ending Serial #
Housing
Thermostat Cover
Thermostat & Gasket Kit
Thermostat
Gaskets Req.
Gaskets Req. - Design II
Gaskets Req. - Design III
ROVER
3140000
UP
18-3551
60
68/L4
1965-1968
1887079
2049044
18-3551
80
80/L4
1966-1969
2049045
2851423
18-3551
90
96/L4
1970-1972
2851424
3226957
18-3557
18-2831
100 VASER
98/L4
2007-2010
w995000
&UP
18-1508
110
153/L4
1963-1966
1537370
2044033
❹
18-3551
110
153/L4
1963-1966
1821720
2044033
❺
18-3551
120
153/L4
1964-1972
1666601
3377340
❹
18-3551
120
153/L4
1964-1966
1725593
2046624
❺
18-3551
120
153/L4
1967
2046625
2324346
❺
18-3551
120
153/L4
1968-1972
2324347
3377340
18-3650 ❺, ➂
18-3650
18-3550
18-2831
120
153/L4
1972-1986
3377341
B531853
18-3650 ➂
18-3650
18-3550
18-2831
2.5L
153/L4
1987-1989
B531854
C853255
18-3650 ➂
18-3650
18-3550
18-2831
140
181/L4
1968-1986
2508261
B450800
18-3650 ➂
18-3650
18-3550
18-2831
140 (6 CYL)
1538930
1725960
—
18-3551
—
❶ Design I
❷ Design II
❸ Design III
❹ Aluminum Exhaust Manifold ❺ Cast Iron Exhaust Manifold ❻ Closed Cooling
❼ Standard Cooling ❽ With check ball
❾ Without check ball
❿ SN 4167000 & Up
➀ Original thermostat housing listed as NLA. Order update kit 87290A23 ➁ Original thermostat housing listed as NLA. Order update kit 90736A24 ➂ Complete thermostat housing kit kit
➃ Single and 3-point drain system
➄ 7-point drain system
➅ Mechanical Throttle Body
➆ Digital Throttle Body
➇ Emission Control Engine
➈ Manual drain system
➉ Air Actuated drain system
☞ Old Design
♠ New Design
♣ 160 degree
♥ For Stainless Steel version use 18-1989
759
I/O — MERCRUISER - Cooling System