Mercruiser Thermostats

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Sierra Thermostat

Mallory Thermostat

ROVER 3140000 UP 18-3551 9-43013
60 1887079 2049044 18-3551 9-43013
80 2049045 2851423 18-3551 9-43013
90 2851424 3226957 18-3557 9-43024
110 1537370 2044033 18-3551 9-43013
120 (1)1666601 3377340 18-3551 9-43013
120 (2)1725593 2324346 18-3551 9-43013
120/2.5L (2)2324347 UP 18-3550 9-43020
140 (6 CYL) 1538930 1725960 18-3551 9-43013
140 (4 CYL)/3.0L 2508261 UP 18-3550 9-43020
3.0L/3.0LX C856559 UP 18-3550 9-43020
150 1666495 2048046 18-3551 9-43013
160 (1)2048022 2770031 18-3551 9-43013
160 (2)2048022 2233574 18-3557 9-43024
160 (2)2326069 2770031 18-3557 9-43024
165 2770032 5813433 18-3550 9-43020
165/3.7L (4 CYL) 6916779 UP 18-3555 9-43001
170 (4 CYL) 6916779 UP 18-3555 9-43001
175/4.3L, 4.3LX (262 CID) (3)B527955 UP 18-3551 9-43013
175/4.3L, 4.3 LX (262 CID) (4)B527955 UP 18-3551 9-43013
175/4.3L, 4.3 LX (262 CID) (4)F001220 UP 18-3649 (7)9-43002
180/3.7L-LX (4 CYL) 6916779 UP 18-3555 9-43001
185 (229 CID) 6330183 6919655 18-3551 9-43013
185 (262 CID) A331455 B527954 18-3551 9-43013
190 1564539 1730903 18-3551 9-43013
190 (4 CYL) 6916779 UP 18-3555 9-43001
200 2453769 2712072 18-3557 9-43024
200 GM 6218462 B525981 18-3551 9-43013
200/5.0L 0B525982 0F600999 18-3649 9-43002
200/5.0L GM (3)B525982 UP 18-3551 9-43013
200/5.0L GM (4)B525982 UP 18-3649 (7)9-43002
205 (262 CID) A331455 B527954 18-3551 9-43013
205/4.3L, 4.3LX (262 CID) (3)B527955 D714369 18-3551 9-43013
205/4.3L, 4.3 LX (262 CID) (4)B527955 D714369 18-3551 9-43013
205/4.3L, 4.3 LX (262 CID) (4)F001220 UP 18-3649 (7)9-43002
215 FORD 2781153 3040410 18-3551 9-43013
215 FORD 3040411 UP 18-3551 9-43013
215 FORD MCM/MIE 3040411 3385720 18-3649 9-43002
225 FORD MCM/MIE 3385721 4176999 18-3649 9-43002
225 GM 1539620 2278646 18-3551 9-43013
225 GM 2278647 2399197 18-3551 9-43013
225 GM 2399198 2694014 18-3551 9-43013
225/225S FORD 3385721 UP 18-3551 9-43013
228 GM MCM/MIE 4765100 6218461 18-3649 9-43002
228 GM 4765100 6218461 18-3551 9-43013
228 GM 6218462 B525981 18-3551 9-43013
230 GM 6218462 B525981 18-3551 9-43013
230 MIE 5907058 0B5225505 18-3649 9-43002
230 GM IB (5)5907058 B522505 18-3551 9-43013
230 GM IB (6)5907058 B522505 18-3551 9-43013
230/5.0L GM IB (5)B522506 B525981 18-3551 9-43013
230/5.0L GM IB (5)B522506 B525981 18-3649 (7)9-43002
230/5.0L GM IB (6)B522506 B525981 18-3551 9-43013
230/5.0L-LX GM (3)B525982 F600999 18-3551 9-43013
230/5.0L-LX GM (4)B525982 UP 18-3551 9-43013
230/5.0L GM IB (4)B522506 B525981 18-3649 (7)9-43002
230/5.0L-LX GM B525982 F600999 18-3649 (7)9-43002
230/5.0L MIE 0B522506 0B788151 18-3649 9-43002
230/5.0LX GM 0B525982 0F600999 18-3649 9-43002
233 FORD 4173000 UP 18-3551 9-43013
233 FORD MIE 4173000 4902304 18-3649 9-43002
250 GM 2314301 2639854 18-3551 9-43013
250 GM 4768000 4908849 18-3551 9-43013
250 GM 4768000 4908849 18-3649 9-43002
250 GM MCM/MIE 2314301 2639854 18-3649 9-43002
250 GM MCM/MIE 4175500 5907057 18-3649 9-43002
255 FORD 3258728 UP 18-3551 9-43013
255 FORD MCM/MIE 3258728 4178299 18-3649 9-43002
255 GM 4175500 4767999 18-3551 9-43013
260 GM 4908850 6218461 18-3551 9-43013
260 GM 6218462 B525981 18-3551 9-43013
260 GM 4908850 6218461 18-3649 9-43002
260 GM IB (5)5907058 B522505 18-3551 9-43013
260 GM IB (6)5907058 B522505 18-3551 9-43013
260 MIE 5907058 0B522505 18-3649 9-43002
260/5.7L GM IB (5)B522506 B525981 18-3551 9-43013
260/5.7L GM IB (5)B522506 B525981 18-3551 9-43013
260/5.7L GM IB (5)B522506 B525981 18-3649 (7)9-43002
260/5.7L GM IB (6)B522506 B525981 18-3551 9-43013
260/5.7L GM (3)B525982 F600999 18-3551 9-43013
260/5.7L GM (4)B525982 F600999 18-3551 9-43013
260/5.7L GM (4)B525982 F600999 18-3649 (7)9-43002
260/5.7L GM 0B525982 0F600999 18-3649 9-43002
260/5.7L MIE 0B522506 0F024999 18-3649 9-43002
262 MAG ALPHA 0F803800 0K999999 18-3649 9-43002
262 MAG BRAVO 0F803800 0K999999 18-3649 9-43002
350 Mag B525982 F600999 18-3551 9-43013
4.3L/LX GM 0F000878 0F601126 18-3649 9-43002
4.3L/LX/LXH ALPHA 0F601127 0K999999 18-3649 9-43002
4.3L/LX/LXH BRAVO 0F601127 0K999999 18-3649 9-43002
4.3L/LH/EFI ALPHA 0L010044 UP 18-3649 9-43002
4.3L/LH/EFI 0L010044 UP 18-3649 9-43002
5.0L/EFI ALPHA 0L012052 UP 18-3649 9-43002
5.0L/EFI BRAVO 0L012052 UP 18-3649 9-43002
5.7 GM ALPHA 0F225560 0K999999 18-3649 9-43002
5.7 GM BRAVO 0F225560 0K999999 18-3649 9-43002
5.7L/EFI GM ALPHA 0L010037 UP 18-3649 9-43002
5.7L/EFI GM BRAVO 0L010037 UP 18-3649 9-43002
5.7 GM (SKI) A338553 B514626 18-3551 9-43013
5.7L SKI 0B514627 UP 18-3649 9-43002
5.7 GM SKI/BRAVO (3)B514627 UP 18-3551 9-43013
5.7 GM SKI/BRAVO (4)B514627 UP 18-3551 9-43013
5.7 GM SKI/BRAVO (4)B514627 UP 18-3649 (7)9-43002
5.7L MIE 0F025000 0F622099 18-3649 9-43002
5.7L MIE 0F622100 0K999999 18-3649 9-43002
5.7L MIE 0F622100 0K999999 18-3649 9-43002
5.7L MIE 0L002003 UP 18-3649 9-43002
270 GM 2851074 3077735 18-3551 9-43013
270 GM MCM/MIE 2851074 3385720 18-3649 9-43002
280 GM 4176250 4770199 18-3649 9-43002
280 GM TRS 4176250 4770199 18-3551 9-43013
300 MR/TRS GM 6668677 B430367 18-3551 9-43013
320 GM EFI A543604 UP 18-3551 9-43013
320 GM 0A543604 0C622418 18-3649 9-43002
325 GM MCM/MIE 2278747 3780449 18-3649 9-43002
325 GM 2278747 2313964 18-3551 9-43013
325 GM 2313965 3042730 18-3551 9-43013
325 GM 3042731 UP 18-3551 9-43013
330 GM 4623115 UP 18-3551 9-43013
330 GM MCM/MIE 4623115 0B816540 18-3649 9-43002
330 GM W/BW (5)6083145 UP 18-3551 9-43013
330 GM W/BW (6)6083145 UP 18-3551 9-43013
340/7.4L GM IB (5)5889914 UP 18-3551 9-43013
340/7.4L GM IB (5)5889914 UP 18-3551 9-43013
340/7.4L GM IB (6)5889914 UP 18-3551 9-43013
340/7.4L MIE 5889914 0D715493 18-3649 9-43002
350 MAG 0B252882 0K999999 18-3649 9-43002
350 MAG 0B252882 0K999999 18-3649 9-43002
350 MAG SKI 0D505450 0K999999 18-3649 9-43002
350 MAG EFI SKI 0F215561 0K999999 18-3649 9-43002
350 MAG MPI/MIE 0L010019 UP 18-3649 9-43002
350 MAG MPI SKI 0F350583 UP 18-3649 9-43002
SCORPION SKI 0F800000 UP 18-3649 9-43002
7.4 BRAVO GM (3)B771113 D603117 18-3551 9-43013
7.4 BRAVO GM (4)B771113 UP 18-3551 9-43013
7.4 BRAVO GM (4)D603118 UP 18-3649 (7)9-43002
7.4L W/HURTH IB (5)C391564 D715493 18-3551 9-43013
7.4L W/HURTH IB (6)C391564 UP 18-3551 9-43013
7.4L W/HURTH IB D715494 UP 18-3649 (7)9-43002
7.4L/LX GM 0F352000 0K999999 18-3649 9-43002
7.4L MPI/TBI 0F563052 UP 18-3649 9-43002
7.4L MIE 0C391564 0D715493 18-3649 9-43002
7.4L MIE 0C391564 0F349999 18-3649 9-43002
7.4L MIE 0D715494 0F820141 18-3649 9-43002
7.4L MIE 0F820142 0K999999 18-3649 9-43002
7.4L MIE 0F820142 0K999999 18-3649 9-43002
350 GM 3780450 UP 18-3551 9-43013
350 GM (MAGNUM) A635178 B525981 18-3551 9-43013
350 GM (MAGNUM) (3)B525982 UP 18-3551 9-43013
350 GM (MAGNUM) (4)B525982 UP 18-3551 9-43013
350 GM (MAGNUM) (4)B525982 UP 18-3649 (7)9-43002
350 MIE 3780450 4623109 18-3649 9-43002
370 GM 4179554 6721527 18-3649 9-43002
370 TRS GM 4179554 6721527 18-3551 9-43013
370 TRS GM 6721528 UP 18-3551 9-43013
390 GM 2781129 2825059 18-3551 9-43013
390 GM MCM/MIE 2781129 3042731 18-3649 9-43002
400 GM 4179554 0B457644 18-3649 9-43002
400 TRS GM 4179554 UP 18-3551 9-43013
420 GM A398941 UP 18-3551 9-43013
420 GM 0A398941 0B622418 18-3649 9-43002
440 TRS GM 4179554 UP 18-3551 9-43013
454 GM MAGNUM/ALPHA (3)A631894 B785148 18-3551 9-43013
454 GM MAGNUM/BRAVO (4)A631894 UP 18-3551 9-43013
454 GM MAGNUM/BRAVO (4)B721206 UP 18-3649 (7)9-43002
454 MAG MCM/SKI 0F305000 0K999999 18-3649 9-43002
460 TRS GM 4179554 UP 18-3551 9-43013
470 4208730 6218036 18-3552 9-43000
470 6218037 UP 18-3555 9-43000
485 5685394 UP 18-3552 9-43000
488 6170297 UP 18-3555 9-43000
500(Gen V) F213293 F615766 18-3551 9-43013
502 EFI/MPI MCM 0F8026000 0K999999 18-3649 9-43002
502 MAG MPI 0L017000 UP 18-3649 9-43002
575 GM 0A677429 0D763716 18-3649 9-43002
575 A677429 UP 18-3551 9-43013
8.2L MIE 0D857200 0F350274 18-3649 9-43002
8.2L MIE 0F350275 0F819619 18-3649 9-43002
8.2L MIE 0D857200 0F819619 18-3649 9-43002
8.2L MPI/MIE 0F819620 UP 18-3649 9-43002
888 FORD 3108723 UP 18-3551 9-43013
888 FORD MCM 3108723 4887829 18-3649 9-43002
898/198 GM 4762210 6218461 18-3551 9-43013
898/198 GM MCM/MIE 4762210 6218461 18-3649 9-43002
898 GM 6218462 UP 18-3551 9-43013

Engine / Model

Beginning S/N

Ending S/N

Sierra Thermostat

Mallory Thermostat

Notes:
  • (1) : Aluminum Manifold
  • (2) : Cast Iron
  • (3) : Old Design
  • (4) : New Design
  • (5) : Std. Cooling
  • (6) : Closed Cooling
  • (7) : 160°
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Engine / Model :
Your Price: $18.97
Save: $7.51
(28% Off $26.48)
Part # 18-3549 ValueShip™ Eligible
Replaces OEM part #
  • MERCURY MARINE 14586
  • For: 6, 7, 8, 9.9, 15 & 30 Hp Mercury/Mariner -A197112& later
  • 120 degrees
Your Price: $14.67
Save: $4.44
(23% Off $19.11)
Part # 18-3550 ValueShip™ Eligible
Replaces OEM part #
  • MERCURY MARINE 59078
Your Price: $11.99
Save: $2.06
(14% Off $14.05)
Part # 18-3551 ValueShip™ Eligible
Replaces OEM part #
  • CHRYSLER INBOARD 4142885
  • CRUSADER 96319
  • PLEASURECRAFT RO26002E
  • MERCURY MARINE 59137
For: Ford 302/351 CID engines, and Crusader models:CH190 (305 CID), CH220 (305 CID), CH270 (350 CID), CH350 (454 CID)
Your Price: $13.47
Save: $3.74
(21% Off $17.21)
Part # 18-3552 ValueShip™ Eligible
No Reviews  |  Write Review  |  Ask Question
Replaces OEM part #
  • CRUSADER 96358
  • MERCURY MARINE 76270T
  • MERCURY MARINE 76270
Fresh Water Cooling Only
For: Crusader Models: 165 (229 CID), CH190/CH220 (305 CID), CH270 (350 CID), CH350 (454 CID)
Your Price: $14.22
Save: $4.11
(22% Off $18.33)
Part # 18-3555 ValueShip™ Eligible
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Replaces OEM part #
  • MERCURY MARINE 99155A1
Your Price: $20.57
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(28% Off $28.83)
Part # 18-3557 ValueShip™ Eligible
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1" - 143 Degree

Replaces OEM part #
  • CHRYSLER FORCE F335068
  • OMC 382385
  • OMC 396987
  • MERCURY MARINE 47594
Your Price: $18.13
Save: $7.77
(30% Off $25.90)
Part # 18-3649 ValueShip™ Eligible
Fresh Water Cooling
Use with 18-2917 Gasket

Replaces OEM part #
  • CRUSADER 97895
  • MERCURY MARINE 807252-2
Your Price: $16.99 Discontinued
Save: $11.55
(40% Off $28.54)
Part # 9-43024 ValueShip™ Eligible
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Replaces Original Equipment Manufacturer(OEM):CHRYSLER FORCE
Replaces Original Equipment Manufacturer # (OEM #):F335068
Your Price: $9.99 Discontinued
Save: $6.21
(38% Off $16.20)
Part # 9-43000 ValueShip™ Eligible
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Replaces GLM #:13050
Replaces Original Equipment Manufacturer(OEM):Mercruiser / Crusader
Replaces Original Equipment Manufacturer # (OEM #):76270T / 96358
Fits Application:160 degree
Your Price: $11.99 Discontinued
Save: $7.95
(39% Off $19.94)
Part # 9-43017 ValueShip™ Eligible
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Replaces Original Equipment Manufacturer(OEM):Mercruiser
Replaces Original Equipment Manufacturer # (OEM #):863358
Fits Application:496 magnum & HO , 8.1L MIE & HO
Your Price: $11.99 Discontinued
Save: $7.95
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Part # 9-43015 ValueShip™ Eligible
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Replaces Original Equipment Manufacturer(OEM):Mercruiser
Replaces Original Equipment Manufacturer # (OEM #):864493
Your Price: $10.99 Discontinued
Save: $7.16
(39% Off $18.15)
Part # 9-43016 ValueShip™ Eligible
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Replaces Original Equipment Manufacturer(OEM):Mercruiser
Replaces Original Equipment Manufacturer # (OEM #):99155-1
Fits Application:160 degree 1998 & newer V-6 & V-8 w/closed cooling
Thermostat - 18-43017 - Sierra
Your Price: $17.50
Save: $2.91
(14% Off $20.41)
Part # 18-43017 ValueShip™ Eligible
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Replaces OEM Part #:
  • Indmar S985009
  • Mercury 863358
  • Mercury 863358T
Your Price: $18.11
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(14% Off $21.13)
Part # 18-43015 ValueShip™ Eligible
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Replaces OEM Part #:
  • Mercury 864493
Sierra
Average Customer Review for Thermostat 120 Degrees - 18-3549 - Sierra
Full StarFull StarFull StarFull StarFull Star Based On 1 Review | Write Review
Full StarFull StarFull StarFull StarFull StarJust worked
by Bob from Surrey, British Columbia on March 01, 2013
pretty much just had to fit and work...it did both so i'm happy.
(0 of 1 people found this review helpful)
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Average Customer Review for Thermostat 140 Degrees - 18-3550 - Sierra
Full StarFull StarFull StarFull StarEmpty Star Based On 1 Review | Write Review
Full StarFull StarFull StarFull StarEmpty StarQuick shipping
by Jeremiah from Arkansas City, Kansas on August 03, 2014
Quality part and good price.
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Average Customer Review for Thermostat 142 Degrees - 18-3551 - Sierra
Full StarFull StarFull StarFull StarFull Star Based On 1 Review | Write Review
Full StarFull StarFull StarFull StarFull StarGreat Product
by Chad from Milton, Florida on August 05, 2013
Worked as advertised and showed up on time.
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Average Customer Review for Thermostat 160 Degrees - 18-3649 - Sierra
Full StarFull StarFull StarFull StarEmpty Star Based On 3 Reviews | Write Review
Full StarFull StarFull StarEmpty StarEmpty StarThermostat
by Eduardo from Gloucester, Virginia on June 15, 2015
This is the right product. But it should have come with gasket. Everyone knows you need to replace the gasket when replacing the thermostat. Well everyone except for this company!!!!
Was this review helpful?
Full StarFull StarFull StarFull StarFull StarGood value
by Larry from Bakersfield, California on May 26, 2014
Good item, but it should also come with the gaskets, I had to find them somewhere else.
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Full StarFull StarFull StarFull StarFull StarReview for Sierra 18-3649 Thermostat 160 Degrees
by a Customer on March 20, 2009
(0 of 1 people found this review helpful)
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Q:
Does this include the gasket?
A:
This is thermostat only.
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