Water Pumps and Accessories - Mercury Sea Pumps

Stainless Steel Gen 7 Sea Pump for Mercury 496
Starting From:
$549.99

This Part has options, please click the button below to order.

Stainless Steel Gen 7 Plus Sea Pump for Mercury 350 Mag, 496 Mag / HO, 8.2L Mag and 502 Mag - With Pulley

625-413 + Option(s)

Stainless Steel Gen 7 PLUS Sea Pump for Mercury 350 Mag, 496 MAG /HO, 8.2L Mag and 502 Mag - With Pulley

oem to hardin comparison

The NEW and IMPROVED Gen 7 Plus Sea Pump now includes dual seals and dual bearings. The bearing are also 40% larger than OEM bearings leading to even longer pump life!

  • 100-percent factory leak tested to ensure OEM dependability
  • Premium SPEC-approved quality components
  • Premium SPEC-quality seals: utilizing OE face materials provides exceptional heat transfer and low friction
  • Endurance-quality bearings: severe-duty, precision-ground and lubricated Heat-treated bearing shafts to match rollers
  • High-quality, protective packaging

For a number of years now the factory sea pumps have been plagued with a design flaw that made each factory pump a throw away non serviceable item. While the impeller could be serviced it is the factory body that wears out prematurely. Without the proper tolerances these units just won’t pump water. Well, Hardin Marine, the largest manufacturer of all Stainless Steel Sea Pumps set out to again solve the short comings of OEM equipment. By developing a stainless steel 316 heat treated casting Hardin Marine was able to incorporate new dual stainless steel serviceable wear plates as well as the use of a standard common Mercury water impeller. These characteristics have now turned this pump into a serviceable replacement that will provide years of serviceable life span. And all at a fraction of the cost of the original pump. So if you’re out to update and upgrade to a pump that's designed to last a life time, look no further as it has arrived.

Note: This Part includes a pulley already assembled to the pump. The pulley included in the 625-4131 kit is 5-3/4" in outside diameter and WILL NOT replace pulleys from Axius models as the diameter is not the same. This pulley will also not replace the 7" larger diameter pulley #8M2013638. For 7" diameter Axius applications, purchase 625-4130. All product photos show 5-3/4" pulley unless labeled otherwise.

Frequently Asked Questions:

1. Does this pump come complete or do I need to buy any other parts?
A: This pump comes complete, with pulley and it will re-use your factory rear pump inlet.

2. What if my rear pump housing is worn badly?
A: This surface no longer mates to the the new impeller, so it does not matter, the rear housing is now only a water inlet and exit for your new pump.

3. Does this pump feature wear plates on both sides of the impeller?
A: Yes it does, this is a unique feature of this pump, this will allow you to service this pump for years to come without any housing damage.

4. Is any modification required to my factory mounting bracket?
A: No modification is required, this pump was engineered to accept the stock mounting bracket.

5. What impeller does this pump use?
A: This pump features an upgraded larger shaft and bearing assembly and is designed to use the standard Mercruiser sea pump impeller that has been around for 30 years and is readily available across the country. The pump includes an impeller.

6. What OEM sea pumps does this fit and what OEM #'s does it replace?
A:Fits Mercruiser Gen 7 Sea Water Pumps (2000-Present)305/350/377/496 C.I.D 5.0L/5.7L/6.2L/8.1LTBI/MPI/EFI/MAG/Horizon/Scorpio

Replaces Mercury Part Numbers: 468M0122655, 46-8M0118067, 46-862914T08, 46-862914T08P, 46-862914T12, 46-862914A13, 46-862914A13, 46-862914T10, 46-862914T11, 46-862914A13, 46-8M0139996, 46-8M0137217, 0M615000 THRU 0W300012, 0W300013 THRU 0W309999, 0W310000 THRU 0W649999, 0W650000 THRU 1A063239, 1A063240 & Up

7. I'm having possible suction issues with my Mercrusier Gen 7 Pump, what can I do?
A: Check out this link for a troubleshooting guide.


Stainless Steel Gen 7 Sea Pump for Mercury 496
Your Price:
$495.99

Stainless Steel Gen 7 Plus Sea Pump for Mercury 350, 496 and 502 Mag

625-4132

Stainless Steel Gen 7 Plus Sea Pump for Mercury 350 Mag, 496 Mag / HO, 8.2L Mag and 502 Mag (No Pulley)

oem to hardin comparison

The NEW and IMPROVED Gen 7 Plus Sea Pump now includes dual seals and dual bearings. The bearing are also 40% larger than OEM bearings leading to even longer pump life!

NOTE:  YOU CAN PURCHASE THE MODEL WITH PULLEY PRE-INSTALLED (625-4131) BY CLICKING HERE.

  • 100-percent factory leak tested to ensure OEM dependability
  • Premium SPEC-approved quality components
  • Premium SPEC-quality seals: utilizing OE face materials provides exceptional heat transfer and low friction
  • Endurance-quality bearings: severe-duty, precision-ground and lubricated Heat-treated bearing shafts to match rollers
  • High-quality, protective packaging

For a number of years now the factory sea pumps have been plagued with a design flaw that made each factory pump a throw away non serviceable item. While the impeller could be serviced it is the factory body that wears out prematurely. Without the proper tolerances these units just won’t pump water. Well, Hardin Marine, the largest manufacturer of all Stainless Steel Sea Pumps set out to again solve the short comings of OEM equipment. By developing a stainless steel 316 heat treated casting Hardin Marine was able to incorporate new dual stainless steel serviceable wear plates as well as the use of a standard common Mercury water impeller. These characteristics have now turned this pump into a serviceable replacement that will provide years of serviceable life span. And all at a fraction of the cost of the original pump. So if you’re out to update and upgrade to a pump that's designed to last a life time, look no further as it has arrived. Note: Impeller is included.


Stainless Steel Gen 7 Sea Pump for Mercury 496
Starting From:
$499.99

This Part has options, please click the button below to order.

Stainless Steel Gen 8 Sea Pump for Mercury

625-4122 + Option(s)

Stainless Steel Gen 8 Sea Pump for Mercury (No Pulley)

  • 100-percent factory leak tested to ensure OEM dependability
  • Premium SPEC-approved quality components
  • Premium SPEC-quality seals: utilizing OE face materials provides exceptional heat transfer and low friction
  • Endurance-quality bearings: severe-duty, precision-ground and lubricated Heat-treated bearing shafts to match rollers
  • High-quality, protective packaging

This is the new Generation 8 “Extreme Series” sea pump. Hardin Marine, the largest manufacturer of all Stainless Steel Sea Pumps set out to again solve the short comings of OEM equipment. By developing a stainless steel 316 heat treated casting that would incorporate new dual stainless steel serviceable wear plates as well as the use of a standard common water pump impeller.

These characteristics have now turned this pump into a lifetime serviceable replacement pump that will provide years of serviceable life span. And all at a fraction of the cost of the original pump. So if you’re out to update and upgrade to a pump that’s designed to last a lifetime, look no further as it has arrived. Replaces OEM 8M0095465, 8M0118070, 8M0123307, 46-8M0122667. Note: Impeller is included.

NOTE: Click here to figure out if you have the older style (design 1) or newer style (design 2) housing and wear plate.


Lifetime Series Gen 5/6 Standard Mercury Sea Pump
Your Price:
$599.99

This Part has options, please click the button below to order.

Mercruiser Gen 5/6 Replacement Extreme Series Stainless Steel Sea Water Pump

625-4118

Hardin Marine has once again used their racing support and heritage to develop a superior sea pump replacement option for the Mercruiser generation 5/6 application that requires the mechanical fuel pump mounting provision. This pump uses a 316L heat treated Stainless steel snout with a 17-4 hardened pump shaft and high speed roller bearings to provide the ultimate sea pump foundation for years of service. This pump is available in two (2) versions one which is the standard duty unit using a OEM style plastic impeller housing and impeller and a superduty version that employs Hardin's all stainless steel "Life Time" impeller housing with OEM Mercuiser impeller. The pumps are assembled and tested right here in the USA and are the best money can buy.

  • Heavy Duty "Extreme" Version
  • Extreme Series Stainless Steel Housing
  • Hardin Stainless Steel Snout
  • 17-4 Hardened Pump Shaft
  • High Speed Roller Bearings
  • Accepts OEM Factory Pulley
  • Replaces Mercruiser #'s 46-807151A8, 46-8m0084270, 46-807151A31, and 72774A82
  • For parts list, and to buy replacement parts click here

Lifetime Series Gen 5/6 Standard Mercury Sea Pump
Your Price:
$499.99

Mercruiser Gen 5/6 Replacement Standard Duty Sea Water Pump

625-4112

This pump is the standard duty unit using a OEM style plastic impeller housing and impeller. The pumps are assembled and tested right here in the USA and are the best money can buy.

  • Standard Duty Version
  • OEM Style Plastic Housing
  • High Speed Roller Bearings
  • Accepts OEM Factory Pulley
  • Replaces Mercruiser #'s 46-807151A8 and 72774A82

Stainless Steel Sea Pump Assembly
Your Price:
$399.99

Mercruiser Gen 4 Extreme Series Stainless Steel Sea Water Pump

625-4110

Stainless Steel Sea Pump Assembly

Finally a Sea Water Pump designed to last a life time. Hardin Marine has taken their years of sea water pump manufacturing experience and designed an all new stainless steel water pump to replace the factory pot metal and plastic style pumps used on original equipment applications.

These pumps are cast from 316L high quality stainless steel and each pump uses a double roller bearing style snout assembly while integrating a one piece rear impeller housing. These housings will not crack and erode like the factory style units. A factory style press on pump mandrel can be used to accommodate most pulleys. A unique feature to this pump is that the rear housing has 1"npt female inlet/outlet ports so that a wide range of fittings and hose connections can be used for ease of installation.

If your looking for what could possible be the last sea water pump you ever buy look no further as this is the finest direct replacement sea pump on the market today.

Replaces a sierra #18-3600 and Mercruiser 46-72774A32 and 46-807151A12. Also replaces two-piece raw water pump. Fits most Bravo, TR, TRS applications

Comes with Impeller


Stainless Steel Sea Pump Assembly
Your Price:
$299.99

Mercruiser Gen 4 Standard Duty Sea Water Pump

625-4111

Stainless Steel Snout / OEM Housing Sea Pump Assembly

    Replaces:
  • Sierra #18-3600
  • Mercruiser 46-72774A32 and 46-807151A12

Hardin Marine has taken their years of sea water pump manufacturing experience and blended their Extreme Series Sea Pump with an OEM style housing. These snout assembly on these pumps are cast from 316L high quality stainless steel and each pump uses a double roller bearing style snout assembly while integrating a one piece OEM plastic rear impeller housing. Replaces two-piece raw water pump. Fits most Bravo, TR, TRS applications


Gen 4 Stainless Steel Pump And Bracket Mercury Sea Pump Assembly V-Belt
Your Price:
$599.99

Gen 4 Stainless Steel Pump And Bracket Mercury Sea Pump Assembly - V-Belt

625-4100

Gen 4 Stainless Steel Pump And Bracket Mercury Sea Pump Assembly V-Belt

These are new Stainless Steel replacement sea pumps. We have configured options so that you may buy just a replacement pump only or bracket only or even an entire replacement pump assembly including the mounting bracket, V-groove pulley and mandrel. This model include a beautifully polished billet bracket and V-Belt Pulley and Mandrel.

NOTE: Billet bracket cannot be used in Circ Pump applications!


Gen 4 Stainless Steel Pump And Bracket Mercury Sea Pump Assembly - Serpentine
Your Price:
$639.99

Gen 4 SS Pump And Bracket Mercury Sea Pump Assembly - Serpentine - BBC

625-4103

Gen 4 Stainless Steel Pump And Bracket Mercury Sea Pump Assembly Serpentine - BBC

These are new Stainless Steel replacement sea pumps. We have configured options so that you may buy just a replacement pump only or bracket only or even an entire replacement pump assembly including the mounting bracket, Serpentine pulley and mandrel. This model include a beautifully polished billet bracket and Serpentine Pulley and Mandrel.

NOTE: Billet bracket cannot be used in Circ Pump applications!


Gen 4 Stainless Steel Mercury Pump Complete Assembly
Your Price:
$529.99

This Part has options, please click the button below to order.

Gen 4 Stainless Steel Mercury Pump Complete Assembly - BBC Applications

625-4109

New Gen 4 Stainless Steel Mercury Pump Assembly with Stamped Steel Bracket & Billet V-Groove Pulley - BBC Applications

These are new Stainless Steel replacement sea pumps. We have configured options so that you may buy just a replacement pump only or bracket only or even an entire replacement pump assembly including the mounting bracket, V-groove pulley and mandrel.


Gen 4 Stainless Steel Mercury Pump Complete Assembly
Your Price:
$599.99

Stainless Steel SBC Mercury Pump Complete Assembly

625-4107

Stainless Steel SBC Mercury Pump Complete Assembly

These are new Stainless Steel replacement sea pumps. We have configured options so that you may buy just a replacement pump only or bracket only or even an entire replacement pump assembly including the mounting bracket, V-groove pulley and mandrel. This model include a beautifully polished billet bracket and V-Belt Pulley and Mandrel. 

NOTE: Billet bracket cannot be used in Circ Pump applications!

2 Stage Conversion for factory Gen 5 & 6 Sea Pumps
Your Price:
$1,254.99

2 Stage Sea Pump for 525/700 Mercury Racing Applications Dual Outlet

625-4176

2 Stage sea pump for HP525 ,600SCI, and 700SCI Mercury Racing applications

  • Dual 1" common inlet, 2x 1" outlets

One of many of Hardin Marines latest cooling innovations in a new two stage sea pump for the popular Mercury Racing HP525, 600SCI, 662SCI, and 700SCI engines. Engine builders have been pleading for a solution to the lack of water that the factory sea pump delivers and Hardin Marine rose to the occasion with the development of this product. Finally an answer to failed headers from water starvation and detonating engines from under supplied intercoolers.

This pump is designed to retrofit to all Mercury Generation 5/6 engines equipped with a sea pump mounted fuel pump. This pump accepts the OEM factory mechanical fuel pumps that are integrated components in the OEM fuel system and provide additional priming support to the factory EFI system. On the supercharged engines this unit is perfect to solve the cooling system short comings of the factory single stage sea water pump system that splits the single water supply to feed the factory intercooler.

Note: Pulley is not included


2 Stage Sea Pump for 525/700 Mercury Racing Applications Single Common Outlet
Your Price:
$1,315.99

2 Stage Sea Pump for 525/700 Mercury Racing Applications Single Common Outlet

625-4219

2 Stage Sea Pump for 525/700 Mercury Racing Applications

  • Single 1-1/4" outlet common outlet

One of many of Hardin Marines latest cooling innovations in a new two stage sea pump for the popular Mercury Racing HP525, 600SCI, 662SCI, and 700SCI engines. Engine builders have been pleading for a solution to the lack of water that the factory sea pump delivers and Hardin Marine rose to the occasion with the development of this product. Finally an answer to failed headers from water starvation and detonating engines from under supplied intercoolers.

This pump is designed to retrofit to all Mercury Generation 5/6 engines equipped with a sea pump mounted fuel pump. This pump accepts the OEM factory mechanical fuel pumps that are integrated components in the OEM fuel system and provide additional priming support to the factory EFI system. On the supercharged engines this unit is perfect to solve the cooling system short comings of the factory single stage sea water pump system that splits the single water supply to feed the factory intercooler.

Note: Pulley is not included


2 Stage Conversion for factory Gen 5 & 6 Sea Pumps
Your Price:
$1,299.99

2 Stage Sea Pump for Gen 4 & 6 Mercury Applications

625-4134

2 Stage Sea Pump for Gen 4 & 6 Mercury Applications

  • Dual 1" common inlet, 2 x 1" outlets

Note: Pulley is not included, image shown is rendering not actual item.


Replacement Mercury Sea Pump for Mercury 1075 - Gen 1
Your Price:
$1,669.99

Replacement Mercury Sea Pump for Mercury 1075 - Gen 1

625-4141

Replacement Mercury Sea Pump for Mercury 1075 SCi - Gen 1

Built to the highest standards in order to ensure maximum performance this pump is designed to last a lifetime. This pump replaces Design I and II model pumps for Mercury 1075 SCi Gen 1. Will replace OEM #'s 840048A05, and 841359A01. Pulley is Not Included. Will not replace Design III model pumps. The 3 stage inlet has an aluminum inlet with spacer.


Brass Seawater Pump w/ SS Fittings 46-807151A12
Your Price:
$530.99

Brass Seawater Pump w/ SS Fittings 46-807151A12

700-12093

Brass Seawater Pump w/ SS Fittings- For engines with V-belt replaces MerCruiser part # 46-807151A12, 46-72774A32

All Brass Seawater Pump with Stainless Steel Fittings


Replacement Seawater Pump For Mercruiser Gen 5, with Pulley
Your Price:
$480.99

Replacement Seawater Pump For Mercruiser Gen 5, with Pulley

700-12212

Replacement Seawater Pump For Mercruiser Gen 5, with Pulley. For engines with V-belt replaces MerCruiser part # 46-807151A8 and 72774A82. Imported.


Replacement Complete Seawater Pump For Mercruiser Gen 7, with Pulley
Your Price:
$505.99

Replacement Complete Seawater Pump For Mercruiser Gen 7, with Pulley

700-12114

Replacement Seawater Pump For Mercruiser Gen 7, with Pulley. For engines with Serpentine-belt replaces MerCruiser part # 46-8M0122655. Imported.


Replacement Seawater Pump For Mercruiser Gen 7, No Pulley
Your Price:
$334.99

This Part has options, please click the button below to order.

Replacement Seawater Pump For Mercruiser Gen 7, No Pulley

700-12112

Replacement Seawater Pump For Mercruiser Gen 7 replaces MerCruiser part # 46-8M0118062. Imported.


Replacement Mercury Sea Pump for Mercury 1075
Your Price:
$1,539.99

Replacement Mercury Sea Pump for Mercury 1075

625-4140

Replacement Mercury Sea Pump for Mercury 1075 SCi

Built to the highest standards in order to ensure maximum performance this pump is designed to last a lifetime. This pump replaces Design I and II model pumps for Mercury 1075 SCi. Will replace OEM #'s 840048A05 and 841359A01. Pulley is Not Included. Will not replace Design III model pumps. The 3 stage inlet has a stainless down turn inlet.