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Mercruiser Thermostats

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Sierra Thermostat

Mallory Thermostat

ROVER3140000UP18-3551 9-43013
601887079204904418-3551 9-43013
802049045285142318-3551 9-43013
902851424322695718-3557 9-43024
1101537370204403318-3551 9-43013
120(1)1666601337734018-3551 9-43013
120(2)1725593232434618-3551 9-43013
120/2.5L(2)2324347UP18-3550 9-43020
140 (6 CYL)1538930172596018-3551 9-43013
140 (4 CYL)/3.0L2508261UP18-3550 9-43020
3.0L/3.0LXC856559UP18-3550 9-43020
1501666495204804618-3551 9-43013
160(1)2048022277003118-3551 9-43013
160(2)2048022223357418-3557 9-43024
160(2)2326069277003118-3557 9-43024
1652770032581343318-3550 9-43020
165/3.7L (4 CYL)6916779UP18-3555 9-43001
170 (4 CYL)6916779UP18-3555 9-43001
175/4.3L, 4.3LX (262 CID)(3)B527955UP18-3551 9-43013
175/4.3L, 4.3 LX (262 CID)(4)B527955UP18-3551 9-43013
175/4.3L, 4.3 LX (262 CID)(4)F001220UP18-3649(7) 9-43002
180/3.7L-LX (4 CYL)6916779UP18-3555 9-43001
185 (229 CID)6330183691965518-3551 9-43013
185 (262 CID)A331455B52795418-3551 9-43013
1901564539173090318-3551 9-43013
190 (4 CYL)6916779UP18-3555 9-43001
2002453769271207218-3557 9-43024
200 GM6218462B52598118-3551 9-43013
200/5.0L0B5259820F60099918-3649 9-43002
200/5.0L GM(3)B525982UP18-3551 9-43013
200/5.0L GM(4)B525982UP18-3649(7) 9-43002
205 (262 CID)A331455B52795418-3551 9-43013
205/4.3L, 4.3LX (262 CID)(3)B527955D71436918-3551 9-43013
205/4.3L, 4.3 LX (262 CID)(4)B527955D71436918-3551 9-43013
205/4.3L, 4.3 LX (262 CID)(4)F001220UP18-3649(7) 9-43002
215 FORD2781153304041018-3551 9-43013
215 FORD3040411UP18-3551 9-43013
215 FORD MCM/MIE3040411338572018-3649 9-43002
225 FORD MCM/MIE3385721417699918-3649 9-43002
225 GM1539620227864618-3551 9-43013
225 GM2278647239919718-3551 9-43013
225 GM2399198269401418-3551 9-43013
225/225S FORD3385721UP18-3551 9-43013
228 GM MCM/MIE4765100621846118-3649 9-43002
228 GM4765100621846118-3551 9-43013
228 GM6218462B52598118-3551 9-43013
230 GM6218462B52598118-3551 9-43013
230 MIE59070580B522550518-3649 9-43002
230 GM IB(5)5907058B52250518-3551 9-43013
230 GM IB(6)5907058B52250518-3551 9-43013
230/5.0L GM IB(5)B522506B52598118-3551 9-43013
230/5.0L GM IB(5)B522506B52598118-3649(7) 9-43002
230/5.0L GM IB(6)B522506B52598118-3551 9-43013
230/5.0L-LX GM(3)B525982F60099918-3551 9-43013
230/5.0L-LX GM(4)B525982UP18-3551 9-43013
230/5.0L GM IB(4)B522506B52598118-3649(7) 9-43002
230/5.0L-LX GMB525982F60099918-3649(7) 9-43002
230/5.0L MIE0B5225060B78815118-3649 9-43002
230/5.0LX GM0B5259820F60099918-3649 9-43002
233 FORD4173000UP18-3551 9-43013
233 FORD MIE4173000490230418-3649 9-43002
250 GM2314301263985418-3551 9-43013
250 GM4768000490884918-3551 9-43013
250 GM4768000490884918-3649 9-43002
250 GM MCM/MIE2314301263985418-3649 9-43002
250 GM MCM/MIE4175500590705718-3649 9-43002
255 FORD3258728UP18-3551 9-43013
255 FORD MCM/MIE3258728417829918-3649 9-43002
255 GM4175500476799918-3551 9-43013
260 GM4908850621846118-3551 9-43013
260 GM6218462B52598118-3551 9-43013
260 GM4908850621846118-3649 9-43002
260 GM IB(5)5907058B52250518-3551 9-43013
260 GM IB(6)5907058B52250518-3551 9-43013
260 MIE59070580B52250518-3649 9-43002
260/5.7L GM IB(5)B522506B52598118-3551 9-43013
260/5.7L GM IB(5)B522506B52598118-3551 9-43013
260/5.7L GM IB(5)B522506B52598118-3649(7) 9-43002
260/5.7L GM IB(6)B522506B52598118-3551 9-43013
260/5.7L GM(3)B525982F60099918-3551 9-43013
260/5.7L GM(4)B525982F60099918-3551 9-43013
260/5.7L GM(4)B525982F60099918-3649(7) 9-43002
260/5.7L GM0B5259820F60099918-3649 9-43002
260/5.7L MIE0B5225060F02499918-3649 9-43002
262 MAG ALPHA0F8038000K99999918-3649 9-43002
262 MAG BRAVO0F8038000K99999918-3649 9-43002
350 MagB525982F60099918-3551 9-43013
4.3L/LX GM0F0008780F60112618-3649 9-43002
4.3L/LX/LXH ALPHA0F6011270K99999918-3649 9-43002
4.3L/LX/LXH BRAVO0F6011270K99999918-3649 9-43002
4.3L/LH/EFI ALPHA0L010044UP18-3649 9-43002
4.3L/LH/EFI0L010044UP18-3649 9-43002
5.0L/EFI ALPHA0L012052UP18-3649 9-43002
5.0L/EFI BRAVO0L012052UP18-3649 9-43002
5.7 GM ALPHA0F2255600K99999918-3649 9-43002
5.7 GM BRAVO0F2255600K99999918-3649 9-43002
5.7L/EFI GM ALPHA0L010037UP18-3649 9-43002
5.7L/EFI GM BRAVO0L010037UP18-3649 9-43002
5.7 GM (SKI)A338553B51462618-3551 9-43013
5.7L SKI0B514627UP18-3649 9-43002
5.7 GM SKI/BRAVO(3)B514627UP18-3551 9-43013
5.7 GM SKI/BRAVO(4)B514627UP18-3551 9-43013
5.7 GM SKI/BRAVO(4)B514627UP18-3649(7) 9-43002
5.7L MIE0F0250000F62209918-3649 9-43002
5.7L MIE0F6221000K99999918-3649 9-43002
5.7L MIE0F6221000K99999918-3649 9-43002
5.7L MIE0L002003UP18-3649 9-43002
270 GM2851074307773518-3551 9-43013
270 GM MCM/MIE2851074338572018-3649 9-43002
280 GM4176250477019918-3649 9-43002
280 GM TRS4176250477019918-3551 9-43013
300 MR/TRS GM6668677B43036718-3551 9-43013
320 GM EFIA543604UP18-3551 9-43013
320 GM0A5436040C62241818-3649 9-43002
325 GM MCM/MIE2278747378044918-3649 9-43002
325 GM2278747231396418-3551 9-43013
325 GM2313965304273018-3551 9-43013
325 GM3042731UP18-3551 9-43013
330 GM4623115UP18-3551 9-43013
330 GM MCM/MIE46231150B81654018-3649 9-43002
330 GM W/BW(5)6083145UP18-3551 9-43013
330 GM W/BW(6)6083145UP18-3551 9-43013
340/7.4L GM IB(5)5889914UP18-3551 9-43013
340/7.4L GM IB(5)5889914UP18-3551 9-43013
340/7.4L GM IB(6)5889914UP18-3551 9-43013
340/7.4L MIE58899140D71549318-3649 9-43002
350 MAG0B2528820K99999918-3649 9-43002
350 MAG0B2528820K99999918-3649 9-43002
350 MAG SKI0D5054500K99999918-3649 9-43002
350 MAG EFI SKI0F2155610K99999918-3649 9-43002
350 MAG MPI/MIE0L010019UP18-3649 9-43002
350 MAG MPI SKI0F350583UP18-3649 9-43002
SCORPION SKI0F800000UP18-3649 9-43002
7.4 BRAVO GM(3)B771113D60311718-3551 9-43013
7.4 BRAVO GM(4)B771113UP18-3551 9-43013
7.4 BRAVO GM(4)D603118UP18-3649(7) 9-43002
7.4L W/HURTH IB(5)C391564D71549318-3551 9-43013
7.4L W/HURTH IB(6)C391564UP18-3551 9-43013
7.4L W/HURTH IBD715494UP18-3649(7) 9-43002
7.4L/LX GM0F3520000K99999918-3649 9-43002
7.4L MPI/TBI0F563052UP18-3649 9-43002
7.4L MIE0C3915640D71549318-3649 9-43002
7.4L MIE0C3915640F34999918-3649 9-43002
7.4L MIE0D7154940F82014118-3649 9-43002
7.4L MIE0F8201420K99999918-3649 9-43002
7.4L MIE0F8201420K99999918-3649 9-43002
350 GM3780450UP18-3551 9-43013
350 GM (MAGNUM)A635178B52598118-3551 9-43013
350 GM (MAGNUM)(3)B525982UP18-3551 9-43013
350 GM (MAGNUM)(4)B525982UP18-3551 9-43013
350 GM (MAGNUM)(4)B525982UP18-3649(7) 9-43002
350 MIE3780450462310918-3649 9-43002
370 GM4179554672152718-3649 9-43002
370 TRS GM4179554672152718-3551 9-43013
370 TRS GM6721528UP18-3551 9-43013
390 GM2781129282505918-3551 9-43013
390 GM MCM/MIE2781129304273118-3649 9-43002
400 GM41795540B45764418-3649 9-43002
400 TRS GM4179554UP18-3551 9-43013
420 GMA398941UP18-3551 9-43013
420 GM0A3989410B62241818-3649 9-43002
440 TRS GM4179554UP18-3551 9-43013
454 GM MAGNUM/ALPHA(3)A631894B78514818-3551 9-43013
454 GM MAGNUM/BRAVO(4)A631894UP18-3551 9-43013
454 GM MAGNUM/BRAVO(4)B721206UP18-3649(7) 9-43002
454 MAG MCM/SKI0F3050000K99999918-3649 9-43002
460 TRS GM4179554UP18-3551 9-43013
4704208730621803618-3552 9-43000
4706218037UP18-3555 9-43000
4855685394UP18-3552 9-43000
4886170297UP18-3555 9-43000
500(Gen V)F213293F61576618-3551 9-43013
502 EFI/MPI MCM0F80260000K99999918-3649 9-43002
502 MAG MPI0L017000UP18-3649 9-43002
575 GM0A6774290D76371618-3649 9-43002
575A677429UP18-3551 9-43013
8.2L MIE0D8572000F35027418-3649 9-43002
8.2L MIE0F3502750F81961918-3649 9-43002
8.2L MIE0D8572000F81961918-3649 9-43002
8.2L MPI/MIE0F819620UP18-3649 9-43002
888 FORD3108723UP18-3551 9-43013
888 FORD MCM3108723488782918-3649 9-43002
898/198 GM4762210621846118-3551 9-43013
898/198 GM MCM/MIE4762210621846118-3649 9-43002
898 GM6218462UP18-3551 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°
Refine Parts List
Engine / Model

Blowout
Save 19%-40% Off.
Thermostat 120 Degrees - 18-3549 - Sierra
Your Price: $18.75
Save: $7.43
(28% Off $26.18)
Part # 18-3549 ValueShip™ Eligible
SHIPS TODAY!* if ordered in 7 hrs 15 mins. Replaces OEM part #
  • MERCURY MARINE 14586
  • For: 6, 7, 8, 9.9, 15 & 30 Hp Mercury/Mariner -A197112& later
  • 120 degrees
Thermostat 140 Degrees - 18-3550 - Sierra
Meltdown Sale Price: $15.29
Save: $3.63
(19% Off $18.92)
Part # 18-3550 ValueShip™ Eligible
SHIPS TODAY!* if ordered in 7 hrs 15 mins. Replaces OEM part #
  • MERCURY MARINE 59078
Thermostat 142 Degrees - 18-3551 - Sierra
Meltdown Sale Price: $9.89
Save: $3.46
(25% Off $13.35)
Part # 18-3551 ValueShip™ Eligible
SHIPS TODAY!* if ordered in 7 hrs 15 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)
Crusader Thermostat 160 Degrees - 18-3552 - Sierra
Your Price: $12.98
Save: $3.61
(21% Off $16.59)
Part # 18-3552 ValueShip™ Eligible
SHIPS TODAY!* if ordered in 7 hrs 15 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)
Thermostat 160 Degrees - 18-3555 - Sierra
Meltdown Sale Price: $14.39
Save: $3.76
(20% Off $18.15)
Part # 18-3555 ValueShip™ Eligible
No Reviews | Write Review | Ask Question
Replaces OEM part #
  • MERCURY MARINE 99155A1
Thermostat - 18-3557 - Sierra
Your Price: $20.35
Save: $8.19
(28% Off $28.54)
Part # 18-3557 ValueShip™ Eligible
SHIPS TODAY!* if ordered in 7 hrs 15 mins.
No Reviews | Write Review | Ask Question
1" - 143 Degree

Replaces OEM part #
  • CHRYSLER FORCE F335068
  • OMC 382385
  • OMC 396987
  • MERCURY MARINE 47594
Thermostat 160 Degrees - 18-3649 - Sierra
Your Price: $17.98
Save: $7.69
(29% Off $25.67)
Part # 18-3649 ValueShip™ Eligible
SHIPS TODAY!* if ordered in 7 hrs 15 mins. Fresh Water Cooling
Use with 18-2917 Gasket

Replaces OEM part #
  • CRUSADER 97895
  • MERCURY MARINE 807252-2
Mallory Thermostat (143) 9-43024
Meltdown Sale Price: $16.87
Save: $11.67
(40% Off $28.54)
Part # 9-43024 ValueShip™ Eligible
SHIPS TODAY!* if ordered in 7 hrs 15 mins.
No Reviews | Write Review | Ask Question
Replaces Original Equipment Manufacturer(OEM):CHRYSLER FORCE
Replaces Original Equipment Manufacturer # (OEM #):F335068
Mallory Thermostat 9-43000
Meltdown Sale Price: $9.83
Save: $6.37
(39% Off $16.20)
Part # 9-43000 ValueShip™ Eligible
SHIPS TODAY!* if ordered in 7 hrs 15 mins.
No Reviews | Write Review | Ask Question
Replaces GLM #:13050
Replaces Original Equipment Manufacturer(OEM):Mercruiser / Crusader
Replaces Original Equipment Manufacturer # (OEM #):76270T / 96358
Fits Application:160 degree
Mallory Thermostat 9-43017
Meltdown Sale Price: $12.57
Save: $7.37
(36% Off $19.94)
Part # 9-43017 ValueShip™ Eligible
SHIPS TODAY!* if ordered in 7 hrs 15 mins.
Hurry! Only 1 left in stock
No Reviews | Write Review | Ask Question
Replaces Original Equipment Manufacturer(OEM):Mercruiser
Replaces Original Equipment Manufacturer # (OEM #):863358
Fits Application:496 magnum & HO , 8.1L MIE & HO
Mallory Thermostat 9-43015
Meltdown Sale Price: $12.57
Save: $7.37
(36% Off $19.94)
Part # 9-43015 ValueShip™ Eligible
SHIPS TODAY!* if ordered in 7 hrs 15 mins.
No Reviews | Write Review | Ask Question
Replaces Original Equipment Manufacturer(OEM):Mercruiser
Replaces Original Equipment Manufacturer # (OEM #):864493
Mallory Thermostat 9-43016
Meltdown Sale Price: $11.26
Save: $6.89
(37% Off $18.15)
Part # 9-43016 ValueShip™ Eligible
SHIPS TODAY!* if ordered in 7 hrs 15 mins.
Hurry! Only 1 left in stock
No Reviews | Write Review | Ask Question
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
Thermostat - 18-43017 - Sierra
Meltdown Sale Price: $15.27
Part # 18-43017 ValueShip™ Eligible
SHIPS TODAY!* if ordered in 7 hrs 15 mins.
No Reviews | Write Review | Ask Question
Replaces OEM Part #:
  • Indmar S985009
  • Mercury 863358
  • Mercury 863358T
Thermostat - 18-43015 - Sierra
Meltdown Sale Price: $15.81 (Out of stock)
Part # 18-43015 ValueShip™ Eligible
No Reviews | Write Review | Ask Question
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)
Was this review helpful?
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.
Was this review helpful?
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.
Was this review helpful?
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.
Was this review helpful?
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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