991551 Marine Boat Replacement Thermostat 

Mercruiser Thermostat 991551

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MSRP: $36.25
Your Price: $34.99
You Save: 3% off MSRP!

NOTE: This Item is a Non-Stocked, Special Order, OEM Mercury Part.
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Applications Where This Item Is Used:

350 MAG MPI MX 6.2L MPI INBOARD - MX 6.2L MPI HORIZON MIE454 MAG MPI HORIZON AND 8.2L MIE MPI - 454 MAG. MPI HORIZON (GEN. VI) GM 454 V-8
7.4L/8.2L MPI (MIE) GEN VI - 7.4L MIE MPI (LH) GEN. VI GM 454 V-8 1996-1997350/6.2L MAG MPI (MIE) (GEN+) - MX 6.2L MPI MIE
454/502 MPI MAG BRAVO (GEN VI) - 502 MAG. MPI BRAVO (GEN VI) GM 502 V-84.3L ALPHA/BRAVO (262 CID - GEN +) - 4.3LH (GEN +) (4 BBL.) GM 262 V-6 1998
350 MAG MPI MX 6.2L MPI INBOARD - 350 MAG MPI HORIZON MIE5.0L EFI ALPHA/BRAVO 5.7L EFI ALPHA/BRAVO (GEN +) ENGINE - 5.0L EFI GM 305 V-8 1998
454/502 MPI MAG BRAVO (GEN VI) - 454 MAG. MPI BRAVO (GEN VI) GM 454 V-84.3L EFI ALPHA/BRAVO (262 CID - GEN+) - 4.3L EFI (GEN+) TBI GM 262 V-6
7.4L EFI (MIE) HURTH/BORG WARNER (GEN VI) - 7.4L TBI MIE (LH) GEN. VI GM 454 V-8 1996-1997454 MAG MPI HORIZON/MIE 8.2L MPI - 8.2L MIE MPI (GEN. VI) GM 502 V-8
5.0L/5.7L ALPHA/BRAVO GEN+ - 5.0L (2 BBL.) GM 305 V-8 1998-20015.0L/5.7L ALPHA/BRAVO GEN+ - 5.7L (2 BBL.) GM 350 V-8 1998-2001
454/502 MPI MAG BRAVO (GEN VI) - 502 MAG MPI BRAVO (GEN VI) GM 502 V-8 1998350 MAG MPI (GEN+)MIE - 350 MAG. MPI MIE (GEN+) GM 350 V-8 1998
454 MAG MPI HORIZON AND 8.2L MIE MPI - 8.2L MIE MPI (GEN. VI) GM 502 V-85.0L / 5.7L EFI ALPHA/BRAVO (GEN +) ENGINE - 5.7L EFI GM 350 V-8 1999-2001
5.0L,350 MAG,MX 6.2L MPI STERNDRIVE - MX 6.2L MPI HORIZON BRAVO4.3L EFI ALPHA/BRAVO (262 C.I.D. GEN+) - 4.3L EFI (GEN+) TBI GM 262 V-6
5.0L,350 MAG,MX 6.2L MPI STERNDRIVE - 350 MAG MPI HORIZON ALPHA/BRAVO7.4L MPI (MIE) (GEN VI-L29) - 7.4L MPI MIE (L29) GEN. VI GM 454 V-8 1998-2000
5.7L CARB (MIE) (GEN+) - 5.7L CARB MIE5.7L EFI (MIE)TBI (GEN+) - 5.7L EFI MIE GM 350 V-8 1997
5.0L,350 MAG,MX 6.2L MPI STERNDRIVE - 5.0L MPI ALPHA/BRAVO7.4L/8.2L MPI (MIE) GEN VI - 8.2L MIE MPI (LH) GEN. VI GM 502 V-8 1996-1997
454/502 MPI MAG BRAVO (GEN VI) - 454 MAG MPI BRAVO (GEN VI) GM 454 V-8 1998350/6.2L MAG MPI (MIE) (GEN+) - 350 MAG MPI HORIZON MIE
MX 6.2L MPI BRAVO ENGINE - MX 6.2L MPI BRAVO454 MAG MPI HORIZON/MIE 8.2L MPI - 454 MAG. MPI HORIZON (GEN. VI) GM 454 V-8
4.3L MPI ALPHA/BRAVO( 262 C.I.D. MULTI PORT INJECTION ) - 4.3L MPI ALPHA/BRAVO7.4L MPI BRAVO L29 (GEN VI) - 7.4L BRAVO (MPI)(GEN. VI) GM 454 V-8 1998-2000
5.0L EFI ALPHA/BRAVO 5.7L EFI ALPHA/BRAVO (GEN +) ENGINE - 5.7L EFI GM 350 V-8 1998350 MAGNUM MPI ALPHA/BRAVO (GEN+) ENGINE - 350 MAG MPI ALPHA/BRAVO
5.0L / 5.7L EFI ALPHA/BRAVO (GEN +) ENGINE - 5.0L EFI GM 305 V-8 1999-20015.0L / 5.7L EFI ALPHA/BRAVO (GEN +) ENGINE - 5.0L EFI GM 305 V-8 1999-2001
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