Multi-Stage Water Pumps - Dual Stage Sea Water Pumps

2 Stage Stainless Steel Sea Pump
Your Price:
$799.99

2 Stage Stainless Steel Sea Pump

625-4940

2 Stage Stainless Steel Sea Pump

The dual stage Extreme Sea Pump is the next step in our line of high performance, high volume raw water pumps. Incorporating two individual impellers this pump will double the volume of water delivered to your engine or give you the choice of separate routing to individual engine components. Dual stage pumps are commonly found on high horsepower pleasure boat applications where a dual independent water pump for an an intercooler, exhaust system or oil coolers is advantageous.

Available in either: Billet Aluminum or Stainless Steel, this dual stage sea pump is the key to solving over heating problems.


2 Stage Stainless Steel Sea Pump with 1 Groove Pulley, 1-1/4” NPT Center Inlet & Dual 1” NPT Outlets
Your Price:
$1,099.99

2 Stage Stainless Steel Sea Pump with 1 Groove Pulley, 1-1/4" NPT Center Inlet & Dual 1" NPT Outlets

625-4942

2 Stage Stainless Steel Sea Pump with 1 Groove Pulley, 1-1/4” NPT Center Inlet & Dual 1” NPT Outlets

The dual stage Extreme Sea Pump is the next step in our line of high performance, high volume raw water pumps. Incorporating two individual impellers this pump will double the volume of water delivered to your engine or give you the choice of separate routing to individual engine components. Dual stage pumps are commonly found on high horsepower pleasure boat applications where a dual independent water pump for an an intercooler, exhaust system or oil coolers is advantageous.

Available in either: Billet Aluminum or Stainless Steel, this dual stage sea pump is the key to solving over heating problems.


2 Stage Stainless Steel Sea Pump with 1 Groove Pulley, 1-1/4” NPT Center Inlet/Outlet
Your Price:
$1,169.99

2 Stage Stainless Steel Sea Pump with 1 Groove Pulley, 1-1/4" NPT Center Inlet/Outlet

625-4941

2 Stage Stainless Steel Sea Pump with 1 Groove Pulley, 1-1/4” NPT Center Inlet/Outlet

The dual stage Extreme Sea Pump is the next step in our line of high performance, high volume raw water pumps. Incorporating two individual impellers this pump will double the volume of water delivered to your engine or give you the choice of separate routing to individual engine components. Dual stage pumps are commonly found on high horsepower pleasure boat applications where a dual independent water pump for an an intercooler, exhaust system or oil coolers is advantageous.

Available in either: Billet Aluminum or Stainless Steel, this dual stage sea pump is the key to solving over heating problems.


2 Stage Stainless Steel Sea Pump with 2 Groove Pulley, 1-/4” NPT Center Inlet/Outlet
Your Price:
$1,189.99

2 Stage Stainless Steel Sea Pump with 2 Groove Pulley, 1-/4" NPT Center Inlet/Outlet

625-4951

2 Stage Stainless Steel Sea Pump with 2 Groove Pulley, 1-/4” NPT Center Inlet/Outlet

The dual stage Extreme Sea Pump is the next step in our line of high performance, high volume raw water pumps. Incorporating two individual impellers this pump will double the volume of water delivered to your engine or give you the choice of separate routing to individual engine components. Dual stage pumps are commonly found on high horsepower pleasure boat applications where a dual independent water pump for an an intercooler, exhaust system or oil coolers is advantageous.

Available in either: Billet Aluminum or Stainless Steel, this dual stage sea pump is the key to solving over heating problems.


2 Stage Stainless Steel Sea Pump with 2 Groove Pulley, 1-/4” NPT Center Inlet & Dual 1” NPT Outlets
Your Price:
$1,129.99

2 Stage Stainless Steel Sea Pump with 2 Groove Pulley, 1-1/4" NPT Center Inlet & Dual 1" NPT Outlets

625-4952

2 Stage Stainless Steel Sea Pump with 2 Groove Pulley, 1-/4” NPT Center Inlet & Dual 1” NPT Outlets

The dual stage Extreme Sea Pump is the next step in our line of high performance, high volume raw water pumps. Incorporating two individual impellers this pump will double the volume of water delivered to your engine or give you the choice of separate routing to individual engine components. Dual stage pumps are commonly found on high horsepower pleasure boat applications where a dual independent water pump for an an intercooler, exhaust system or oil coolers is advantageous.

Available in either: Billet Aluminum or Stainless Steel, this dual stage sea pump is the key to solving over heating problems.


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.


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 Aluminum  Sea Pump
Your Price:
$820.00

2 Stage Aluminum Sea Pump

625-4920

2 Stage Aluminum Sea Pump 

The dual stage Extreme Sea Pump is the next step in our line of high performance, high volume raw water pumps. Incorporating two individual impellers this pump will double the volume of water delivered to your engine or give you the choice of separate routing to individual engine components.

Dual stage pumps are commonly found on high horsepower pleasure boat applications where a dual independent water pump for an an intercooler, exhaust system or oil cooler is advantageous.

Available in either: Billet Aluminum or Stainless Steel, this dual stage sea pump is the key to solving over heating problems.


2 Stage Aluminum  Sea Pump with 1 Groove Pulley, 1-1/4” NPT Center Inlet & Dual 1” NPT Outlets
Your Price:
$1,079.99

2 Stage Aluminum Sea Pump with 1 Groove Pulley, 1-1/4" NPT Center Inlet & Dual 1" NPT Outlets

625-4922

2 Stage Aluminum Sea Pump with 1 Groove Pulley, 1-1/4” NPT Center Inlet & Dual 1” NPT Outlets

The dual stage Extreme Sea Pump is the next step in our line of high performance, high volume raw water pumps. Incorporating two individual impellers this pump will double the volume of water delivered to your engine or give you the choice of separate routing to individual engine components. Dual stage pumps are commonly found on high horsepower pleasure boat applications where a dual independent water pump for an an intercooler, exhaust system or oil coolers is advantageous.

Available in either: Billet Aluminum or Stainless Steel, this dual stage sea pump is the key to solving over heating problems.


2 Stage Aluminum  Sea Pump with 2 Groove Pulley, 1-1/4” NPT Center Inlet & Dual 1” NPT Outlets
Your Price:
$1,099.99

2 Stage Aluminum Sea Pump with 2 Groove Pulley, 1-1/4" NPT Center Inlet & Dual 1" NPT Outlets

625-4932

2 Stage Aluminum Sea Pump with 2 Groove Pulley, 1-1/4” NPT Center Inlet & Dual 1” NPT Outlets

The dual stage Extreme Sea Pump is the next step in our line of high performance, high volume raw water pumps. Incorporating two individual impellers this pump will double the volume of water delivered to your engine or give you the choice of separate routing to individual engine components. Dual stage pumps are commonly found on high horsepower pleasure boat applications where a dual independent water pump for an an intercooler, exhaust system or oil coolers is advantageous.

Available in either: Billet Aluminum or Stainless Steel, this dual stage sea pump is the key to solving over heating problems.


2 Stage Aluminum  Sea Pump wit h1 Groove Pulley, 1-1/4” NPT Center Inlet/Outlet
Your Price:
$1,139.99

2 Stage Aluminum Sea Pump with 1 Groove Pulley, 1-1/4" NPT Center Inlet/Outlet

625-4921

2 Stage Aluminum Sea Pump wit h1 Groove Pulley, 1-1/4” NPT Center Inlet/Outlet

The dual stage Extreme Sea Pump is the next step in our line of high performance, high volume raw water pumps. Incorporating two individual impellers this pump will double the volume of water delivered to your engine or give you the choice of separate routing to individual engine components. Dual stage pumps are commonly found on high horsepower pleasure boat applications where a dual independent water pump for an an intercooler, exhaust system or oil coolers is advantageous.

Available in either: Billet Aluminum or Stainless Steel, this dual stage sea pump is the key to solving over heating problems.


2 Stage Aluminum  Sea Pump with 2 Groove Pulley, 1-1/4” NPT Center Inlet/Outlet
Your Price:
$1,159.99

2 Stage Aluminum Sea Pump with 2 Groove Pulley, 1-1/4" NPT Center Inlet/Outlet

625-4931

2 Stage Aluminum Sea Pump with 2 Groove Pulley, 1-1/4” NPT Center Inlet/Outlet

The dual stage Extreme Sea Pump is the next step in our line of high performance, high volume raw water pumps. Incorporating two individual impellers this pump will double the volume of water delivered to your engine or give you the choice of separate routing to individual engine components. Dual stage pumps are commonly found on high horsepower pleasure boat applications where a dual independent water pump for an an intercooler, exhaust system or oil coolers is advantageous.

Available in either: Billet Aluminum or Stainless Steel, this dual stage sea pump is the key to solving over heating problems.


GM LS Series Engine Dual Stage Sea Water Pump
Your Price:
$1,199.99

GM LS Series Engine Dual Stage Sea Water Pump

625-4117

Hardin Marine is the first to bring a engine specific sea water pump for the popular LS series of engines. This dual stage sea water pump was designed around the 5.3 ,6.0, and 6.2 liter generation engine platforms. The pump uses Hardin Marine's Extreme Lifetime Series stainless steel impeller housing as well as a proprietary short body construction that allows the necessary access or clearance for the engines factory engine mounting pads when the pump is installed. The pump is designed to mount to the engine blocks factory A/C mounting bosses while positioning the billet aluminum serpentine pulley in line with OEM crankshaft pulley. The billet mounting bracket provides the two necessary idlers that allow this pump to be incorporated into most factory automotive serpentine accessory drive systems. The Sea pump features female (2) 1" NPT  and (1) 1-1/4" common inlet and outlet ports for ease of plumbing convenience.

Note: Fits OEM GM LS Corvette / CTS-V / G8 automotive balancer spacing with 1-1/2" offset (NOT Truck or F-Body balancer)

Basic Dual Stage Sea Pump Service Kit
Your Price:
$189.99

Basic Dual Stage Sea Pump Service Kit

625-4181

Basic Dual Stage Sea Pump Service Kit

These kits consist of all the basic service related parts needed to rebuild a Hardin Marine Multi-Stage sea pump as well as many other multi-stage pumps on the market today. Each kit comes with the necessary sealing o-rings, impeller, and stainless steel wear plates.


2 Stage Master Rebuild Kit Gen 2
Your Price:
$219.99

Hardin Dual Stage Gen. 1 Sea Pump Master Rebuild Kit

625-4167

Hardin Dual Stage Gen. 1 Sea Pump Master Rebuild Kit

Replace all the bearings, seals, o-rings, clips, wear plates and impellers on your Hardin Dual Stage Sea Pump.

Gen. 1 Pumps have Black, Hardcoated, Billet Aluminum Rear Covers.
Gen. 2 Pumps have Polished, Cast Stainless Steel Rear Covers with a bolt in the center. The name Hardin Marine is cast into the cover.


2 Stage Master Rebuild Kit Gen 2
Your Price:
$209.99

Hardin Dual Stage Gen. 2 Sea Pump Master Rebuild Kit

625-4170

Hardin Dual Stage Gen. 2 Sea Pump Master Rebuild Kit

Replace all the bearings, seals, o-rings, clips, wear plates and impellers on your Hardin Dual Stage Sea Pump.

Gen. 1 Pumps have Black, Hardcoated, Billet Aluminum Rear Covers.
Gen. 2 Pumps have Polished, Cast Stainless Steel Rear Covers with a bolt in the center. The name Hardin Marine is cast into the cover.


525/700 2 Stage Master Rebuild Kit
Your Price:
$229.99

Hardin 525/700 Dual Stage Master Rebuild Kit

625-4177

Hardin 525/700 Dual Stage Master Rebuild Kit. This kit is designed to used on pump 625-4176 only.

Dual Stage Sea Pump Factory Rebuild
Your Price:
$419.99

Dual Stage Sea Pump Factory Rebuild

625-4191

Dual Stage Sea Pump Factory Rebuild

This is a factory rebuild of your pump. You will need to send your pump in to rebuilt. We will contact you with details when ordered.

2 Stage Stainless Rear Cap / Bearing Upgrade
Your Price:
$319.99

2 Stage Stainless Rear Cap / Bearing Upgrade

625-4163

2 Stage Stainless Rear Cap / Bearing Upgrade

The latest in multi-stage pump design has again advanced. All current series Hardin multi stage sea pumps now feature this roller bearing tail shaft design. If you have an earlier bushing styled tail shaft pump it can now easily be upgrades to the later version with one of our kits. This kit includes a new pump shaft, bearing, seal, and new stainless steel rear cover plate.