Mercruiser Thermostats

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Engine / Model

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Ending S/N

Sierra Thermostat

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

Engine / Model

Beginning S/N

Ending S/N

Sierra Thermostat

Notes:
  • (1) : Aluminum Manifold
  • (2) : Cast Iron
  • (3) : Old Design
  • (4) : New Design
  • (5) : Std. Cooling
  • (6) : Closed Cooling
  • (7) : 160°
Refine Parts List
Engine / Model :
Your Price: $18.02
Save: $8.46
(31% Off $26.48)
Part # 18-3549 ValueShip™ Eligible
SHIPS TODAY!* if ordered in 8 hrs 4 mins.
Replaces OEM part #
  • MERCURY MARINE 14586
  • For: 6, 7, 8, 9.9, 15 & 30 Hp Mercury/Mariner -A197112& later
  • 120 degrees
Your Price: $13.93
Save: $5.18
(27% Off $19.11)
Part # 18-3550 ValueShip™ Eligible
SHIPS TODAY!* if ordered in 8 hrs 4 mins.
Replaces OEM part #
  • MERCURY MARINE 59078
Your Price: $10.99
Save: $3.06
(21% Off $14.05)
Part # 18-3551 ValueShip™ Eligible
SHIPS TODAY!* if ordered in 8 hrs 4 mins.
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: $12.80
Save: $4.41
(25% Off $17.21)
Part # 18-3552 ValueShip™ Eligible
SHIPS TODAY!* if ordered in 8 hrs 4 mins.
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: $11.95
Save: $6.38
(34% Off $18.33)
Part # 18-3555 ValueShip™ Eligible
SHIPS TODAY!* if ordered in 8 hrs 4 mins.
No Reviews  |  Write Review  |  Ask Question
Replaces OEM part #
  • MERCURY MARINE 99155A1
Your Price: $18.90
Save: $9.93
(34% Off $28.83)
Part # 18-3557 ValueShip™ Eligible
SHIPS TODAY!* if ordered in 8 hrs 4 mins.
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1" - 143 Degree

Replaces OEM part #
  • CHRYSLER FORCE F335068
  • OMC 382385
  • OMC 396987
  • MERCURY MARINE 47594
Your Price: $17.23
Save: $8.67
(33% Off $25.90)
Part # 18-3649 ValueShip™ Eligible
SHIPS TODAY!* if ordered in 8 hrs 4 mins.
Fresh Water Cooling
Use with 18-2917 Gasket

Replaces OEM part #
  • CRUSADER 97895
  • MERCURY MARINE 807252-2
Thermostat - 18-43017 - Sierra
Your Price: $14.39
Save: $6.00
(29% Off $20.39)
Part # 18-43017 ValueShip™ Eligible
SHIPS TODAY!* if ordered in 8 hrs 4 mins.
No Reviews  |  Write Review  |  Ask Question
Replaces OEM Part #:
  • Indmar S985009
  • Mercury 863358
  • Mercury 863358T
Your Price: $15.59
Save: $5.54
(26% Off $21.13)
Part # 18-43015 ValueShip™ Eligible
SHIPS TODAY!* if ordered in 8 hrs 4 mins.
No Reviews  |  Write Review  |  Ask Question
Replaces OEM Part #:
  • Mercury 864493
Sierra
Average Customer Review for Sierra 18-3549 - Thermostat 120 Degrees
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!!!!
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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:
Will the Sierra 18-3551 thermostat 142F work for a gray marine 109?
A:
We cannot match it up with your motor. For: Ford 302/351 CID engines, and Crusader models:CH190 (305 CID), CH220 (305 CID), CH270 (350 CID), CH350 (454 CID).
Q:
Does this include the gasket?
A:
This is thermostat only.
Q:
I have a 1979 228 (4BBL) Mercruiser there is a 142 temp and a 160 degree temp that could fit which one should be used.?
A:
For a 1979 you need the 142, part number 18-3551.
Q:
Does this include the gasket?
A:
Yes this includes the gasket.
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