Hardin marine stainless sea water / fuel pump
01-19-2026 | 04:13 PM
#1
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From: Tullahoma Tennessee
Hardin marine stainless sea water / fuel pump
I picked these up this past weekend for my BBC ‘s I am curious to anyone’s thoughts on them? Seem to be quailty built. They have one season on them I picked both of them up for the price of a McDonald combo meal. Hoping I don’t mess up by removing the OEM bravo water pumps cause these sure seem like an upgrade ?
also on the backs of them they just say “ out “ on the water pump which one is in?
also on the backs of them they just say “ out “ on the water pump which one is in?
01-19-2026 | 06:22 PM
#3
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From: Lake Ozark, MO USA
I have 2 with one season on them. My new and 2 season old Merc fuel pump leaked and blew the seal on the Hardin pumps. I just rebuild the sea pumps last week. Those you have are a little older because they do not have the drain holes in the bottom to change the drive oil. The rotation on the housing should show 2 arrows, RH and LH. I don't know what you paid, but the pulleys and mandrels are 130.00 for the combo each from Hardin. I would like to find a couple of them for myself.
01-19-2026 | 06:25 PM
#4
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From: Lake Ozark, MO USA
87, here is a link to their catalog. Click on the video and you can se on the back of the impellor housing how they are set up for connections.
Hardin Marine - Mercruiser Gen 5/6 Replacement Extreme Series Stainless Steel Sea Water Pump
Hardin Marine - Mercruiser Gen 5/6 Replacement Extreme Series Stainless Steel Sea Water Pump
01-19-2026 | 08:31 PM
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From: Lake Ozark, MO USA
01-20-2026 | 07:32 PM
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I do not have any personal experience with the Hardin sea pumps. I did do a lot of reading up on them when I found one for sale at a good price.
It seems some people have differing opinions. Might want to hang onto the OEM pumps just to be safe.
It's prob safe to assume most people have had good results with them.
One of the problems I had read about was the oil reservoir for the fuel pump lubrication builds up pressure and pushed oil past the front seal. Hardin does sell a kit that is supposed to bleed off excess pressure. https://www.hardin-marine.com/p-1044...equalizer.aspx
Another issue I had read about had to do with low or lower water pressure than the OEM pump. Someone was saying there were slight differences in the impeller cavity size that reduced output?
You can do a search on here by typing in Hardin sea pump in the "search" bar and you should see threads about them.
It seems some people have differing opinions. Might want to hang onto the OEM pumps just to be safe.
It's prob safe to assume most people have had good results with them.
One of the problems I had read about was the oil reservoir for the fuel pump lubrication builds up pressure and pushed oil past the front seal. Hardin does sell a kit that is supposed to bleed off excess pressure. https://www.hardin-marine.com/p-1044...equalizer.aspx
Another issue I had read about had to do with low or lower water pressure than the OEM pump. Someone was saying there were slight differences in the impeller cavity size that reduced output?
You can do a search on here by typing in Hardin sea pump in the "search" bar and you should see threads about them.
Last edited by xlint89; 01-21-2026 at 08:32 PM.
01-20-2026 | 11:20 PM
#8
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Joined: Oct 2000
Posts: 20,232
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From: Omaha/LOTO
I do not have any personal experience with the Hardin sea pumps. I did do a lot of reading up on them when I found one for sale at a good price.
It seems some people have differing opinions. Might want to hang onto the OEM pumps just to be safe.
It's prob safe to assume most people have had good results with them.
One of the problems I had read about was the oil reservoir for the fuel pump lubrication builds up pressure and pushed oil past the front seal. Hardin does sell a kit that is supposed to bleed off excess pressure. https://www.hardin-marine.com/p-1044...equalizer.aspx
Another issue I had read about had to do with low or lower water pressure than the OEM pump. Someone was saying there were slight differences in the impeller cavity size that reduced output? If i remember correctly, I think it was Griff that ran one for a couple seasons and switched back to OEM?
You can do a search on here by typing in Hardin sea pump in the "search" bar and you should see threads about them.
It seems some people have differing opinions. Might want to hang onto the OEM pumps just to be safe.
It's prob safe to assume most people have had good results with them.
One of the problems I had read about was the oil reservoir for the fuel pump lubrication builds up pressure and pushed oil past the front seal. Hardin does sell a kit that is supposed to bleed off excess pressure. https://www.hardin-marine.com/p-1044...equalizer.aspx
Another issue I had read about had to do with low or lower water pressure than the OEM pump. Someone was saying there were slight differences in the impeller cavity size that reduced output? If i remember correctly, I think it was Griff that ran one for a couple seasons and switched back to OEM?
You can do a search on here by typing in Hardin sea pump in the "search" bar and you should see threads about them.
01-20-2026 | 11:33 PM
#9
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From: Omaha/LOTO
I have 2 of these set ups. One doesn’t have the pulley. They came off a friend’s boat years ago when he switched to electric pumps. The sea pumps spin smoothly and appear fine.
01-21-2026 | 01:12 PM
#10
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Joined: Jan 2007
Posts: 2,241
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From: Jackson, n.j. ~ Brooklyn, n.y.
Griff....looking for 2 seawater pumps no fuel pumps needed...for BBC 575's was interested in Harden, but way too expensive......right now have 2 cracked ones needing replacement.
