Contact Our Parts Experts: 1-888-625-5460

Hablamos Español

Mercury Outboard Cooling Systems

(148 products)

Water is inducted through the lower unit by a water pump impeller in the cooling system on an outboard and then forced upward to circulate throughout the powerhead, and eventually exits through the exhaust system.

View as

  • Flush-M Mercury Outboard Flushing Solution

    Flush-M

    Flush-M - Mercury Outboard Flushing Solution - Black - 75-450HP Models

    (6)
    $75.00
    Learn More
  • Mercury 3.4L V6 - 4.6L V8 Water Pump Repair Kit - 98-8M0142980

    Mercury

    Mercury 3.4L V6 - 4.6L V8 Water Pump Repair Kit - 98-8M0142980

    (1)
    $47.50 $55.92
    Learn More
  • Mercury - Outboard Water Pump Impeller - Fits 30-40-45-50-60 HP Four Stroke Bigfoot, 60 HP Bigfoot 75-125 HP - 75-90-115 Four Stroke - 150 EFI - V-200 - Mercruiser Alpha One Gen II - 47-43026T2

    Mercury

    Mercury - Outboard Water Pump Impeller - Fits 30-40-45-50-60 HP Four Stroke Bigfoot, 60 HP Bigfoot 75-125 HP - 75-90-115 Four Stroke - 150 EFI - V-200 - Mercruiser Alpha One Gen II - 47-43026T2

    $29.99 $37.08
    Learn More
  • Mercury - Complete Water Pump - Fits 30-60 HP EFI & Carbureted FourStroke - 46-812966A12

    Mercury

    Mercury - Complete Water Pump - Fits 30-60 HP EFI & Carbureted FourStroke - 46-812966A12

    (2)
    $149.99 $174.83
    Learn More
  • Mercury Thermostat With Housing - 8M0137816

    Mercury

    Mercury Thermostat With Housing - 8M0137816

    $110.35 $129.92
    Learn More
  • Mercury - Poppet Valve Kit - Fits V-6 Outboard Models - 803062T1

    Mercury

    Mercury - Poppet Valve Kit - Fits V-6 Outboard Models - 803062T1

    $32.63 $38.42
    Learn More
  • Mercury - Complete Outboard Water Pump Kit - Fits 40-125 HP - 46-8M0113799

    Mercury

    Mercury - Complete Outboard Water Pump Kit - Fits 40-125 HP - 46-8M0113799

    (2)
    $171.49 $199.92
    Learn More
  • Mercury 853792A07 Outboard Water Pump Repair Kit - Fits 25-30 HP EFI Four Stroke

    Mercury

    Mercury 853792A07 Outboard Water Pump Repair Kit - Fits 25-30 HP EFI Four Stroke

    (2)
    $76.09 $89.58
    Learn More
  • Mercury - Outboard Water Pump Impeller - Fits Various Outboards 3.9-9.8 HP - 47-89981

    Mercury

    Mercury - Outboard Water Pump Impeller - Fits Various Outboards 3.9-9.8 HP - 47-89981

    (2)
    $22.99 $26.58
    Learn More
  • Mercury - Water Impeller Repair Kit - Fits 40-45-50 HP Four Stroke - 821354A2

    Mercury

    Mercury - Water Impeller Repair Kit - Fits 40-45-50 HP Four Stroke - 821354A2

    $58.49 $68.33
    Learn More
  • Mercury 47-803748K01 Outboard Water Impeller Repair Kit - Fits 8/9.9 HP Four Stroke

    Mercury

    Mercury 47-803748K01 Outboard Water Impeller Repair Kit - Fits 8/9.9 HP Four Stroke

    $70.99 $86.22
    Learn More
  • Mercury 8M0117413 Outboard Thermostat - Fits 40-60 HP SeaPro EFI Four Stroke

    Mercury

    Mercury 8M0117413 Outboard Thermostat - Fits 40-60 HP SeaPro EFI Four Stroke

    (1)
    $29.09 $34.25
    Learn More
  • Mercury - Outboard Water Pump Impeller - Fits Various 30-60 HP Four Stroke - 47-19453T

    Mercury

    Mercury - Outboard Water Pump Impeller - Fits Various 30-60 HP Four Stroke - 47-19453T

    (1)
    $45.99 $53.58
    Learn More
  • Mercury Quicksilver - Water Pump Impeller - Fits 40/45/50/60 FourStroke Bigfoot, 60 BigFoot, 75 125, 75/90/115 FourStroke, 150 EFI FourStroke, V6/V8 FourStroke, V 200 DFI, 135 300 Verado, V 225/250 & MerCruiser Alpha One Gen II Drives - 47-43026Q02

    Mercury

    Mercury Quicksilver - Water Pump Impeller - Fits 40/45/50/60 FourStroke Bigfoot, 60 BigFoot, 75 125, 75/90/115 FourStroke, 150 EFI FourStroke, V6/V8 FourStroke, V 200 DFI, 135 300 Verado, V 225/250 & MerCruiser Alpha One Gen II Drives - 47-43026Q02

    $29.99 $37.08
    Learn More
  • Mercury - Outboard Water Pump Impeller - Fits 9.9 HP Four Stroke MY 2005 - 47-803748

    Mercury

    Mercury - Outboard Water Pump Impeller - Fits 9.9 HP Four Stroke MY 2005 - 47-803748

    $27.53 $32.42
    Learn More
  • Mercury - Water Pump Impeller - Fits Various 15-25 HP - 47-8508910

    Mercury

    Mercury - Water Pump Impeller - Fits Various 15-25 HP - 47-8508910

    $31.92 $37.58
    Learn More
  • Mercury - Complete Water Pump - Fits Mercury/Mariner 8/9.9 HP FourStroke Outboards (non‑BigFoot) 2005 & Newer - 46-803750A03

    Mercury

    Mercury - Complete Water Pump - Fits Mercury/Mariner 8/9.9 HP FourStroke Outboards (non-BigFoot) 2005 & Newer - 46-803750A03

    $114.60 $134.92
    Learn More
  • Mercury - Outboard Water Temperature Sender - Fits V-6 Outboards - 13536A14

    Mercury

    Mercury - Outboard Water Temperature Sender - Fits V-6 Outboards - 13536A14

    $51.25 $60.33
    Learn More
  • Mercury - Outboard Water Temperature Sender - Fits V-6 outboard - 13536A13

    Mercury

    Mercury - Outboard Water Temperature Sender - Fits V-6 outboard - 13536A13

    (1)
    $39.99 $47.08
    Learn More
  • Mercury - IMPLLR DRVSHFT KT - 8M0140001

    Mercury

    Mercury - IMPLLR DRVSHFT KT - 8M0140001

    $104.19 $122.67
    Learn More
  • Mercury - Outboard Complete Water Pump - Fits 30-60 HP - 46-8M0113801

    Mercury

    Mercury - Outboard Complete Water Pump - Fits 30-60 HP - 46-8M0113801

    $174.37 $206.58
    Learn More
  • Mercury - Outboard Water Pump Impeller - Fits Various 25-20 HP Four Stroke and 2-Cycle Outboards - 47-161541

    Mercury

    Mercury - Outboard Water Pump Impeller - Fits Various 25-20 HP Four Stroke and 2-Cycle Outboards - 47-161541

    $27.75 $32.88
    Learn More
  • Mercury - Thermostat - 143 Degrees - 75692

    Mercury

    Mercury - Thermostat - 143 Degrees - 75692

    $20.64 $24.08
    Learn More
  • Flush-M - Suzuki Outboard Flushing Solution - Black - DF25 to DF350HP Models

    Flush-M

    Flush-M - Suzuki Outboard Flushing Solution - Black - DF25 to DF350HP Models

    $75.00
    Learn More
  • Mercury Quicksilver - Outboard Water Pump Impeller - Fits 6/15 HP 2-cycle - 8/9.9 HP Four Stroke - 47-42038Q02

    Mercury

    Mercury Quicksilver - Outboard Water Pump Impeller - Fits 6/15 HP 2-cycle - 8/9.9 HP Four Stroke - 47-42038Q02

    $22.99 $26.58
    Learn More
  • Mercury - Outboard Water Pump Upper Housing - 817275A1

    Mercury

    Mercury - Outboard Water Pump Upper Housing - 817275A1

    $83.81 $98.67
    Learn More
  • Mercury 47-803748K02 Outboard Water Impeller Repair Kit - Fits 9.9 HP Four Stroke

    Mercury

    Mercury 47-803748K02 Outboard Water Impeller Repair Kit - Fits 9.9 HP Four Stroke

    (1)
    $73.49 $91.91
    Learn More
  • Mercury - Sea Water Pump - Fits MCM/MIE 4.3L, 5.0L, 5.7L & 6.2L MPI w/ ECM 555 - 46-8M0139995

    Mercury

    Mercury - Sea Water Pump - Fits MCM/MIE 4.3L, 5.0L, 5.7L & 6.2L MPI w/ ECM 555 - 46-8M0139995

    $615.45
    Learn More
  • Mercury - Outboard Water Pump Impeller - Fits MCM & Outboard Applications - 47-89984T4

    Mercury

    Mercury - Outboard Water Pump Impeller - Fits MCM & Outboard Applications - 47-89984T4

    $40.99 $47.58
    Learn More
  • Mercury - Outboard Water Pump Impeller - Fits Mercury/Mariner 8/9.9 HP Four Stroke MY 2005 - 47-8037481

    Mercury

    Mercury - Outboard Water Pump Impeller - Fits Mercury/Mariner 8/9.9 HP Four Stroke MY 2005 - 47-8037481

    $13.52 $19.10
    Learn More
  • Mercury - Outboard Complete Water Pump - Fits 30 JET - 35 - 40 - 45 - 50 - 70 HP 2 Cycle (2/3/4 Cylinder) - 46-77177A3

    Mercury

    Mercury - Outboard Complete Water Pump - Fits 30 JET - 35 - 40 - 45 - 50 - 70 HP 2 Cycle (2/3/4 Cylinder) - 46-77177A3

    $106.49 $124.50
    Learn More
  • Mercury - Outboard Complete Water Pump - Fits 3.0L DFI - 817275A5

    Mercury

    Mercury - Outboard Complete Water Pump - Fits 3.0L DFI - 817275A5

    $133.49 $155.75
    Learn More
  • Mercury - Water Circulating Pump - Fits GM V‑6 & V‑8 Engines - 46-8M0113734

    Mercury

    Mercury - Water Circulating Pump - Fits GM V‑6 & V‑8 Engines - 46-8M0113734

    $142.99 $166.58
    Learn More
  • Mercury - Outboard Water Pump Impeller - Fits Mercury/Marnier Shiftable 3.3 HP - 4/5 HP 2-cycle - 4/5/6 HP Fourstroke - 47-161543

    Mercury

    Mercury - Outboard Water Pump Impeller - Fits Mercury/Marnier Shiftable 3.3 HP - 4/5 HP 2-cycle - 4/5/6 HP Fourstroke - 47-161543

    $22.93 $27.00
    Learn More
  • Mercury 47-19453T2 Outboard Water Impeller Repair Kit - Fits 50 - 55 - 60 HP 3 Cylinder - 2-cycle

    Mercury

    Mercury 47-19453T2 Outboard Water Impeller Repair Kit - Fits 50 - 55 - 60 HP 3 Cylinder - 2-cycle

    $86.99 $103.54
    Learn More
  • Mercury - Repair kit-w/p - 821354A04

    Mercury

    Mercury - Repair kit-w/p - 821354A04

    (1)
    $80.62 $94.92
    Learn More

Most newer Mercury Marine outboard engines use an enclosed cooling system. This means that there is a small tank on the top of the engine that uses a combination of fresh water and coolant.

This fresh water is circulated through the engine and through a heat exchanger. The fresh water, in this system, absorbs the heat of the engine. Mercury outboard motors are typically designed as open loop cooling systems. Meaning the motor draws water from the host body. That water is circulated through the engine, and fuel pump to maintain prop engine temperatures. After passing through the engine or fuel pump the water is then dumped back into the host body. Water is drawn into the water pump through the intake opening of the lower unit, where it passes through a cavity that ends up entering the pump itself. At that point, the impeller pressures the water into the long inlet tube leading to the bottom side of the powerhead. Internal combustion engine cooling uses either air or liquid to remove the waste heat from an internal combustion engine. For small or special-purpose engines, cooling using air from the atmosphere makes for a lightweight and relatively simple system. Cooling system, apparatus employed to keep the temperature of a structure or device from exceeding limits imposed by needs of safety and efficiency.