Mercruiser Thermostat Housings

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Sierra Thermostat Housing

Mallory Thermostat Housing

185 (229 CID) 6330183 6919655 18-1994 (9)9-42502
185 (262 CID) A331455 B527954 18-1994 (9)9-42502
200 GM 6218462 B525981 18-1994 (9)9-42502
200/5.0L GM (3)B525982 UP 18-1994 (9)9-42502
200/5.0L GM (4)B525982 UP 18-1994 (9)9-42502
205 (262 CID) A331455 B527954 18-1994 (9)9-42502
205/4.3L, 4.3LX (262 CID) (3)B527955 D714369 18-1994 (9)9-42502
228 GM 4765100 6218461 18-1993 -
228 GM 6218462 B525981 18-1994 (9)9-42502
230 GM 6218462 B525981 18-1994 (9)9-42502
230/5.0L-LX GM (3)B525982 F600999 18-1994 (9)9-42502
230/5.0L-LX GM B525982 F600999 18-1994 (9)9-42502
250 GM 4768000 4908849 18-1993 -
255 GM 4175500 4767999 18-1993 -
260 GM 6218462 B525981 18-1994 (9)9-42502
260/5.7L GM (3)B525982 F600999 18-1994 (9)9-42502
350 Mag B525982 F600999 18-1994 (9)9-42502
5.7 GM (SKI) A338553 B514626 18-1994 (9)9-42502
280 GM TRS 4176250 4770199 18-1993 -
300 MR/TRS GM 6668677 B430367 18-1994 (9)9-42502
500(Gen V) F213293 F615766 18-1994 (9)9-42502

Engine / Model

Beginning S/N

Ending S/N

Sierra Thermostat Housing

Mallory Thermostat Housing

Notes:
  • (3) : Old Design
  • (4) : New Design
  • (9) : For stainless steel version use 18-1989
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Engine / Model :
Your Price: $105.66
Save: $42.53
(28% Off $148.19)
Part # 18-1910 ValueShip™ Eligible
Hurry! Only 1 left in stock
Replaces OEM part #
  • MERCURY MARINE 861493A3
Fits: 3.0L GM 181 L/4 (1999-Up)
Your Price: $38.24
Save: $33.95
(47% Off $72.19)
Part # 18-1977-1 ValueShip™ Eligible
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Replaces OEM part #
  • MERCURY MARINE 47441A1
Fits: 225, GM 260, 228, 898/198, 185R, 898R, 228R, 2GR, 350 Mag
Your Price: $183.98
Save: $82.72
(31% Off $266.70)
Part # 18-1989 ValueShip™ Eligible
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Replaces OEM part #
  • MERCURY MARINE 860256A4
  • MERCURY MARINE 861006A
  • MERCURY MARINE 87290A4
(Use 18-1989K Thermostat Service Kit for replacement parts)
Your Price: $10.83
Save: $2.98
(21% Off $13.81)
Part # 18-1989K ValueShip™ Eligible
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Service Kit for 18-1989 Thermostat Housing
Your Price: $238.63
Save: $39.26
(14% Off $277.89)
Part # 18-1993 ValueShip™ Eligible
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Replaces OEM part #
  • MERCURY MARINE 78984A1
Your Price: $139.89
Save: $48.29
(25% Off $188.18)
Part # 18-1994 ValueShip™ Eligible
Hurry! Only 1 left in stock
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Replaces OEM part #
  • MERCURY MARINE 87290A4
For: Stainless Steel Version use 18-1989
Your Price: $302.37
Save: $127.29
(29% Off $429.66)
Part # 18-3531 ValueShip™ Eligible
Hurry! Only 1 left in stock
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Replaces OEM part #
  • MERCURY MARINE 861188A1
Fits: MCM/MIE GM V-6 & V-8 305, 350, 454 & 502 cid engines with closed cooling systems
Your Price: $169.99 (Out of stock)
Save: $74.01
(30% Off $244.00)
Part # 18-3532 ValueShip™ Eligible
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Replaces OEM part #
  • MERCURY MARINE 55331A5
Fits: MCM/MIE GM V6 & V8, 305, 350, 454, and 502cid, engines with closed cooling
Mallory Thermostat Housing 9-42502
Your Price: $160.99 (Out of stock)
Save: $27.19
(14% Off $188.18)
Part # 9-42502 ValueShip™ Eligible
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Replaces GLM #:N/A
Replaces Original Equipment Manufacturer(OEM):Mercruiser
Replaces Original Equipment Manufacturer # (OEM #):87290A4
Fits Application:MCM/MIE GM V6-V8 (305,350,454,502 & 504 cid) early design
Mallory Thermostat Housing 9-42501
Your Price: $221.99 (Out of stock)
Save: $145.36
(39% Off $367.35)
Part # 9-42501 ValueShip™ Eligible
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Replaces Original Equipment Manufacturer(OEM):Mercruiser
Replaces Original Equipment Manufacturer # (OEM #):861188A1
Fits Application:MCM/MIE GM V6-V8 (305,350,454,& 502) w/ closed cooling
Mallory Thermostat Housing 9-42505
Your Price: $122.99
Save: $80.65
(39% Off $203.64)
Part # 9-42505 ValueShip™ Eligible
Replaces Original Equipment Manufacturer(OEM):Mercruiser
Replaces Original Equipment Manufacturer # (OEM #):90736A18
Fits Application:MCM/MIE 185 (229 cid) 330, 340, 7.4L, 454 Mag, 370, 425 & 465
Mercury Marine 47442 A1 replacement parts
Your Price: $33.99 (Out of stock)
Save: $22.26
(39% Off $56.25)
Part # 9-42503 ValueShip™ Eligible
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Replaces Original Equipment Manufacturer(OEM):Mercruiser
Replaces Original Equipment Manufacturer # (OEM #):47442A1
Fits Application:MCM/MIE GM V6-V8 (454 & 502cid) & Hi Perf. 454/482 cid (Off-set Bolt pattern)
Your Price: $385.19
Save: $110.54
(22% Off $495.73)
Part # 18-3530-1 ValueShip™ Eligible
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  • Replaces: 860256A4
  • For: GM V6 and V8 (305 & 350 ci)
Your Price: $103.49 (Out of stock)
Save: $115.70
(52% Off $219.19)
Part # T-20913 ValueShip™ Eligible
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Replaces:
  • Chrysler #'s 2469639 and 2847405
Your Price: $175.18
Save: $148.82
(45% Off $324.00)
Part # T-20978 ValueShip™ Eligible
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Replaces:
  • Mercruiser #'s 76771 and 60427.
Sierra
Average Customer Review for Thermostat Housing Kit - 18-1910 - Sierra
Full StarFull StarEmpty StarEmpty StarEmpty Star Based On 1 Review | Write Review
Full StarFull StarEmpty StarEmpty StarEmpty StarMissing Pieces
by Karen from Palmetto, Florida on July 10, 2015
Thermostat and plastic sleeve for the thermostat were missing. Bolts that should be in the kit that mount the thermostat to the head were substituted for bolts that that don't fit anything on a Mercruiser 3.0...I know because I know every nut and bolt on this engine. They are so big they won't even fit through the holes of the thermostat housing, let alone anything else. Plus the bolts that were provided are cheap carbon steel. Ok for fresh water, completely useless for salt. Moral of the story: don't buy this stuff online unless it's genuine Mercruiser or Quicksilver. All of these boat part websites are selling the same junk. The sad thing is, I bought an exhaust elbow from iboats.com on this same order and it came with more parts than expected plus the bolts were stainless steel. Go figure.
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Average Customer Review for Mallory Thermostat Housing 9-42505
Full StarFull StarFull StarFull StarFull Star Based On 1 Review | Write Review
Full StarFull StarFull StarFull StarFull StarMercruiser Chevy big block 454 cid
by Thomas from Atlantic Highlands, New Jersey on July 07, 2015
Fits and works as expected. Mallory t-stat housing several hundred dollars less than Mercruiser part. Fully painted inside which should protect it from rusting. I boat in sal er, but only have a couple hours of use on it.
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Q:
Will this fit my 2005 mercruiser 3.0 ?
A:
Yes, based on the information you have provided, this should work for your application.
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