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991551 Marine Boat Replacement Thermostat 

Mercruiser Thermostat 991551

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NOTICE: Any images shown are representational ONLY and do not necessarily depict the actual part or included items in a particular part or kit. Mercury has been known to remove items depicted in product images such as screws or gaskets from kits they make without notification. For any product content, fitment or application questions on this part please call Mercury Product Support at 920-929-5040.

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

NOTE: This Item is a Non-Stocked, Special Order, OEM Mercury Part.
ALL OEM Mercury parts may take up to 7-10 days to ship. All OEM Mercury parts are NON-RETURNABLE! Orders placed on all OEM Mercury parts are NON-REFUNDABLE! Please contact us with the part number and we can assist you with more accurate delivery time estimate.
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Additonal Info On This Product:

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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