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SeaSierra

Gasket – Fits Mercury Marine Big Block GM V-8 Engines (Replaces Mercury Marine 27-49110)

$2.50 $4.00
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Gasket – Fits Mercury Marine Big Block GM V-8 Engines (Replaces Mercury Marine 27-49110) is backordered and will ship as soon as it is back in stock.

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You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).

You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).

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Delivery and Shipping

Free standard shipping on all orders under 1 KG

If you have any questions, feel free to email us at info@sierramarines.com, and we’ll get back to you within 20–36 hours.

Product Details

This circulating water pump mount Gasket – Fits Mercury Marine Big Block GM V-8 Engines (454 & 502 cid). It is engineered as a reliable aftermarket solution for ensuring a proper seal and preventing coolant leaks in a wide range of specified powerboat engines.

It serves as a direct substitute for multiple part numbers, including Mercury Marine 27-49110, Sierra Marine 18-0903, GLM 31770, Mallory Marine 9-60066, OMC 3853361/914874, Volvo Penta 3853361, and Yamaha YSG-38600-39-G0.

  • Installation Location: Circulating Water Pump Mount
  • Engine Compatibility: Fits Big Block GM V-8 (454 & 502 cid) engines

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket.

Brand Part Number Superseded By
Mercury Marine 27-49110 27-8M0237307
Quicksilver 27-49110 / 27-8M0237307
Sierra Marine 18-0903
GLM 31770
Mallory Marine 9-60066
OMC 3853361 / 914874
Volvo Penta 3853361
Yamaha Marine YSG-38600-39-G0

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For Mercury Marine engines, please verify your model and serial number range against the list below to ensure accurate fitment.

Brand Model Years OEM Part No. Notes
Mercury Marine 370 TRS 1978–1985 27-49110 GM 454 V-8 4179554 THRU 6721527
Mercury Marine 370 TRS 1985–1987 27-49110 GM 454 V-8 6721528 THRU 0B714586
Mercury Marine 400 TRS 1980–1986 27-49110 GM 454 V-8 4179554 THRU 0B457644
Mercury Marine 420 1987–1989 27-49110 GM 454 V-8 0A398941 THRU 0B622418
Mercury Marine 425 (GEN. V) 1992–1993 27-49110 GM 454 V-8 0A398941 THRU 0D937011
Mercury Marine 425 1990–1992 27-49110 GM 454 V-8 0A398941 THRU 0D937011
Mercury Marine 440 TRS 1983–1986 27-49110 GM 454 V-8 4179554 THRU 0B485220
Mercury Marine 450 (GEN. V) 1995–1996 27-49110 GM 454 V-8 0F347100 THRU 0F347277
Mercury Marine 460 TRS 1983–1986 27-49110 GM 482 V-8 4179554 THRU 6181046
Mercury Marine 465 (GEN. V) 1992–1994 27-49110 GM 502 V-8 0C849992 THRU 0F213244
Mercury Marine 465 1990–1992 27-49110 GM 502 V-8 0C849992 THRU 0F213244
Mercury Marine 500 (GEN. +) 1999 27-49110 GM 502 V-8 0L414639 THRU 0L601036
Mercury Marine 500 (GEN. V) 1994–1995 27-49110 GM 502 V-8 0F213293 THRU 0F615766
Mercury Marine 500 (GEN. V) 1996 27-49110 GM 502 V-8 0F615767 THRU 0F745159
Mercury Marine 500 (GEN. VI) 1997–1998 27-49110 GM 502 V-8 0F745195 THRU 0F877722
Mercury Marine 500 (GEN. VI) 1997–1998 27-49110 GM 502 V-8 0K000001 THRU 0L000737
Mercury Marine 500 (GEN. VI) 1997–1998 27-49110 GM 502 V-8 0L000768 THRU 0L001772
Mercury Marine 500 Bulldog 27-49110 0K000248 THRU 0L001607
Mercury Marine 500 Bulldog 1999–2001 27-49110 0L414620 THRU 0M050281
Mercury Marine 500 Bulldog 1990–1996 27-49110 GM 540 V-8 0C577254 THRU 0F745405
Mercury Marine 500 EFI 27-49110 0L001496 THRU 0L306499
Mercury Marine 500 EFI 27-49110 0L306500 THRU 0L307027
Mercury Marine 500 EFI 27-49110 0L307028 THRU 0L602036
Mercury Marine 500 EFI 27-49110 0M050001 THRU 0M050853
Mercury Marine 500 EFI 27-49110 0M052001 THRU 0M053628
Mercury Marine 500 EFI 27-49110 0M900064 THRU 0M901284
Mercury Marine 500 EFI 27-49110 0M905089 THRU 0M907127
Mercury Marine 520 27-49110 0M970122 & Up
Mercury Marine 525 EFI 27-49110 0M900146 THRU 0M953619
Mercury Marine 525 EFI 27-49110 0M953620 THRU 0M956326
Mercury Marine 525 EFI 27-49110 0M956327 THRU 0M962885
Mercury Marine 525 EFI 27-49110 0M962886 & Up
Mercury Marine 525 SC (Gen VI) 27-49110 0F745260 THRU 0F877734
Mercury Marine 525 SC (Gen VI) 27-49110 0K000012 THRU 0L415623
Mercury Marine 525 SC (GEN. V) 1992–1995 27-49110 GM 454 V-8 0D456000 THRU 0F348963
Mercury Marine 525 SC (GEN. V) 1996 27-49110 GM 454 V-8 0F615814 THRU 0F745215
Mercury Marine 525 SC 1991–1992 27-49110 GM 454 V-8 0D456000 THRU 0F348963
Mercury Marine 540 27-49110 0M970866 & Up
Mercury Marine 565 EFI 27-49110 0M967821 & Up
Mercury Marine 575 1986–1992 27-49110 GM 540 V-8 0A677429 THRU 0D763716
Mercury Marine 575 SCi 27-49110 0L306696 THRU 0L307026
Mercury Marine 575 SCi 27-49110 0L601000 THRU 0L602090
Mercury Marine 575 SCi 27-49110 0M050000 THRU 0M053292
Mercury Marine 575 SCi 27-49110 0M900000 THRU 0M950526
Mercury Marine 600 SC Bobtail 1998 27-49110 0L414734 THRU 0L601186
Mercury Marine 600 SC GEN IV & V 1991–1996 27-49110 GM 502 V-8 0D456489 THRU 0F877642
Mercury Marine 600 SCi 27-49110 0M952908 THRU 0M962885
Mercury Marine 600 SCi 27-49110 0M962886 & Up
Mercury Marine 662 SCi 27-49110 0M956580 THRU 0M962885
Mercury Marine 662 SCi 27-49110 0M962886 & Up
Mercury Marine 700 SCi 27-49110 0M962886 & Up
Mercury Marine 700 SCi 27-49110 0M954560 THRU 0M962885
Mercury Marine 800 SC (GEN. V) 1993–1998 27-49110 GM 572 V-8 0D763836 AND UP
Mercury Marine 900 SC 1997–1999 27-49110 0K000858 THRU 0L602069
Mercury Marine 900 SC Dry Sump 27-49110 0L306805 THRU 0M901290
Mercury Marine 900 SC Dry Sump 2000 27-49110 0L306805 & Up
Mercury Marine 454 EFI (SKI) GEN. V 1995 27-49110 GM 454 V-8 0F215800 THRU 0F820099
Mercury Marine 454 MAG. MPI (SKI) GEN. VI 1996–1997 27-49110 GM 454 V-8 0F820100 THRU 0K999999
Mercury Marine 325 1969–1972 27-49110 GM 427 V-8 2278747 THRU 3780449
Mercury Marine 325 MIE 1968–1974 27-49110 GM 427 V-8 2278747 THRU 3780449
Mercury Marine 330 1977–1981 27-49110 GM 454 V-8 4623115 THRU 6083144
Mercury Marine 330 MIE 1977–1980 27-49110 GM 454 V-8 4623115 THRU 5889913
Mercury Marine 340 MIE W/B/W 1981–1987 27-49110 GM 454 V-8 5889914 THRU 0B788365
Mercury Marine 350 MIE 1974–1976 27-49110 GM 454 V-8 3780450 THRU 4623109
Mercury Marine 390 1969–1970 27-49110 GM 482 V-8 2781129 THRU 2825059
Mercury Marine 390 MIE 1969–1970 27-49110 GM 482 V-8 2781129 THRU 2825059
Mercury Marine 454 MAG. MPI HORIZON (GEN. VI) 27-49110 GM 454 V-8 0L002200 THRU 0L086049
Mercury Marine 454 MAG. MPI HORIZON (GEN. VI) 27-49110 GM 454 V-8 0L086050 THRU 0L674000
Mercury Marine 7.4L MIE (LH) GEN. V 1992–1996 27-49110 GM 454 V-8 0D715494 THRU 0F820141
Mercury Marine 7.4L MIE (LH) GEN. VI 1996–1997 27-49110 GM 454 V-8 0F820142 THRU 0K999999
Mercury Marine 7.4L MIE MPI (LH) GEN. V 1995–1996 27-49110 GM 454 V-8 0F563052 THRU 0F820103
Mercury Marine 7.4L MIE MPI (LH) GEN. VI 1996–1997 27-49110 GM 454 V-8 0F820104 THRU 0K999999
Mercury Marine 7.4l MIE W/B/W 1988–1992 27-49110 GM 454 V-8 0B788366 THRU 0D715493
Mercury Marine 7.4L MIE W/HURTH 1989–1992 27-49110 GM 454 V-8 0C391564 THRU 0D715493
Mercury Marine 7.4L MPI MIE (L29) GEN. VI 1998–2000 27-49110 GM 454 V-8 0L002006 THRU 0L674613
Mercury Marine 7.4L TBI MIE (LH) GEN. VI 1996–1997 27-49110 GM 454 V-8 0F874815 THRU 0K999999
Mercury Marine 8.2L MIE GEN. V 1993–1996 27-49110 GM 502 V-8 0D857200 THRU 0F819619
Mercury Marine 8.2L MIE MPI (GEN. VI) 27-49110 GM 502 V-8 0L002450 THRU 0L086012
Mercury Marine 8.2L MIE MPI (GEN. VI) 27-49110 GM 502 V-8 0L086013 THRU 0L674200
Mercury Marine 8.2L MIE MPI (LH) GEN. VI 1996–1997 27-49110 GM 502 V-8 0F819620 THRU 0K999999
Mercury Marine 8.2L MIE W/HURTH 1990–1992 27-49110 GM 502 V-8 0C878221 THRU 0D857199
Mercury Marine 330 1982–1987 27-49110 GM 454 V-8 6083145 THRU 0B816540
Mercury Marine 454 EFI (GEN. V) 1994–1996 27-49110 GM 454 V-8 0F115700 THRU 0F802349
Mercury Marine 454 MAG MPI BRAVO (GEN VI) 1998 27-49110 GM 454 V-8 0L010029 THRU 0L058399
Mercury Marine 454 MAG. ALPHA 1986–1988 27-49110 GM 454 V-8 0A631894 THRU 0B785148
Mercury Marine 454 MAG. BRAVO (GEN. V) 1992–1994 27-49110 GM 454 V-8 0D805069 THRU 0F304999
Mercury Marine 454 MAG. BRAVO (GEN. V) 1995–1996 27-49110 GM 454 V-8 0F305000 THRU 0F801699
Mercury Marine 454 MAG. BRAVO (GEN. V) 1996–1997 27-49110 GM 454 V-8 0F801700 THRU 0K999999
Mercury Marine 454 MAG. BRAVO 1988–1992 27-49110 GM 454 V-8 0B721206 THRU 0D805068
Mercury Marine 454 MAG. BRAVO MPI (GEN VI) 1996–1997 27-49110 GM 454 V-8 0F802350 THRU 0K999999
Mercury Marine 454 MAG. MPI BRAVO (GEN VI) 27-49110 GM 454 V-8 0L085400 THRU 0M024999
Mercury Marine 502 EFI (GEN. V) 1993–1995 27-49110 GM 502 V-8 0D840650 THRU 0F802599
Mercury Marine 502 MAG MPI BRAVO (GEN VI) 1998 27-49110 GM 502 V-8 0L017000 THRU 0L085432
Mercury Marine 502 MAG. BRAVO (GEN. V) 1992–1993 27-49110 GM 502 V-8 0D824589 THRU 0F114528
Mercury Marine 502 MAG. BRAVO 1990–1992 27-49110 GM 502 V-8 0C878221 THRU 0D824588
Mercury Marine 502 MAG. MPI (GEN VI) 1996 27-49110 GM 502 V-8 0F802600 THRU 0K999999
Mercury Marine 502 MAG. MPI BRAVO (GEN VI) 27-49110 GM 502 V-8 0L085433 THRU 0M024999
Mercury Marine 7.4L BRAVO (GEN. V) 1992–1996 27-49110 GM 454 V-8 0D603118 THRU 0F800699
Mercury Marine 7.4L BRAVO (GEN. VI) 1996–1997 27-49110 GM 454 V-8 0F800700 THRU 0K999999
Mercury Marine 7.4L BRAVO (MPI)(GEN. VI) 1998–2000 27-49110 GM 454 V-8 0L010003 THRU 0M024330
Mercury Marine 7.4L BRAVO 1988–1991 27-49110 GM 454 V-8 0B771113 THRU 0D603117
Mercury Marine 7.4LX BRAVO (MPI)(GEN. V) 1996 27-49110 GM 454 V-8 0F602010 THRU 0F801999
Mercury Marine 7.4LX BRAVO (MPI)(GEN. VI) 1996–1997 27-49110 GM 454 V-8 0F802000 THRU 0K999999
Mercury Marine 7.4LX BRAVO (TBI)(GEN. VI) 1996–1997 27-49110 GM 454 V-8 0F820000 THRU 0K999999
Mercury Marine 8.2L INBOARD (BASE) EC Up to 2A041665 27-49110 2A041665 & Up (source shows both)
Mercury Marine 8.2L INBOARD (Base) EC 27-49110 1A350802 THRU 2A041664
Mercury Marine 8.2L INBOARD (H.O.) EC Up to 2A041665 27-49110 2A041665 & Up (source shows both)
Mercury Marine 8.2L INBOARD (H.O.) EC 27-49110 1A350802 THRU 2A041664
Mercury Marine 8.2L Mag (Base Model) 27-49110 1A351597 & Up
Mercury Marine 8.2L Mag (H.O. Model) 27-49110 1A351597 & Up
Mercury Marine 8.2L Mag EC (Base Model) 27-49110 1A350340 THRU 2A041664
Mercury Marine 8.2L Mag EC (Base Model) 27-49110 2A051742 THRU 2A051742
Mercury Marine 8.2L Mag EC (Base Model) 27-49110 2A041665 THRU 2A051741
Mercury Marine 8.2L Mag EC (Base Model) 27-49110 2A051743 & Up
Mercury Marine 8.2L Mag EC (H.O. Model) 27-49110 1A350340 THRU 2A041664
Mercury Marine 8.2L Mag EC (H.O. Model) 27-49110 2A051741 THRU 2A051741
Mercury Marine 8.2L Mag EC (H.O. Model) 27-49110 2A041665 THRU 2A051740
Mercury Marine 8.2L Mag EC (H.O. Model) 27-49110 2A051742 & Up
Mercury Marine 540 Stroker 4V 27-49110 1G400000 & Up

Technical Specs

Product Type
Gasket
Installation
Circulating Water Pump Mount
Engine Fitment
Fits Big Block GM V-8 (454 & 502 cid) engines
Product Dimensions
1.06" L x 5.13" W x 4.0" H
Weight
0.45 kg (1 pound)

Installation Notes

  1. Disconnect the boat's battery and ensure the engine is cool.
  2. Place a drain pan under the engine and drain the cooling system completely.
  3. Loosen the tensioner to remove the serpentine belt from the water pump pulley.
  4. Carefully unbolt and remove the circulating water pump from the engine block. Note the position of different-sized bolts if applicable.
  5. Thoroughly clean any old gasket material and residue from both the engine block and the water pump mounting surfaces.
  6. Position the new gasket onto the water pump or engine block, ensuring all bolt holes align perfectly.
  7. Reinstall the water pump assembly, hand-tightening the bolts first, then torquing them to the manufacturer's specified sequence and values.
  8. Reinstall the serpentine belt and verify correct tension.
  9. Refill the cooling system with the appropriate coolant.
  10. Reconnect the battery, start the engine, and carefully check for any leaks around the water pump.

Troubleshooting & FAQ

How do I know if this gasket will fit my specific engine?

The most reliable method is to check your engine's model and serial number against our compatibility table. While this gasket fits a wide range of Mercury Marine Big Block GM V-8 engines, serial number ranges are the best way to confirm an exact match.

What are the signs of a failing water pump gasket?

Common symptoms include visible coolant leaks from the front-center of the engine (around the pump), crusty coolant residue on the pump body, and engine overheating warnings. A faint sweet smell of antifreeze after running the engine can also indicate a small leak.

Should I use sealant with this gasket?

Most modern gaskets are designed to be installed dry. However, always refer to your engine's specific service manual. If sealant is recommended, apply a thin, even bead as instructed.

Is this part different from the original OEM gasket?

This is a high-quality aftermarket part designed to meet or exceed OEM specifications for fit, form, and function. The materials are comparable and provide a reliable seal, but it is not an original Mercury Marine part.

OEM vs. Aftermarket?

This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.

Shipping speed & cost

We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.

Warranty & returns

Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.

Safety & Important Info

  • Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
  • This is an aftermarket replacement, not an OEM component.
  • Professional installation is recommended for safety and performance.

About Sea Sierra

  • Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
  • Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
  • Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.

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