Sea pump mounted fuel pump?
#12
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Joined: Mar 2020
Posts: 845
Likes: 502
Thanks for the replies guys.
I've even looked into using the block mounted fuel pump and going raw water pump only. No way can I use the pump on the block and the raw water I currently have. So I started looking into mark IV water pump and mounting bracket. It's getting ridiculous what I am considering just to increase a little more fuel for a mild build. I haven't even considered the raw water pump failure due to the fuel dilution issue either.
Option A: Go with KE fuel pump upgrade and cross fingers it works for me. Replace raw water pump gear lube every 20 hours.
Option B: Block off fuel pump on raw water pump mount and go with electric fuel pump. In reading up on this option, I would need to install a relay to turn pump on with oil pressure. Figure out a way to filter the fuel prior to moving through the pump. Install a fuel pressure regulator of some sort. Run a return hose. Is there something else I missed?
Option C: Run block mounted fuel pump with Mark IV raw water pump. Shim pump to align with other pullies as I read the Mark IV pump is not as long as the gen V.
Option D: Run block mounted fuel pump with some type of crank mounted raw water pump. Although I don't think I have any room for this type of install.
I'd prefer to keep it simple and inexpensive as possible. I'll prob just go with option A and hope for the best. Will most likely tap another hole for a second plug on the raw water pump housing to make fluid changes much easier.
SB, I have not had to deal with the fuel dilution issue so far, but I did buy the engine used and have no idea how many hours are on the raw water pump? I'm just going to use the gear lube and change it frequently for now. It would be curious to see if anyone has tried your idea though.
Thanks again
I've even looked into using the block mounted fuel pump and going raw water pump only. No way can I use the pump on the block and the raw water I currently have. So I started looking into mark IV water pump and mounting bracket. It's getting ridiculous what I am considering just to increase a little more fuel for a mild build. I haven't even considered the raw water pump failure due to the fuel dilution issue either.
Option A: Go with KE fuel pump upgrade and cross fingers it works for me. Replace raw water pump gear lube every 20 hours.
Option B: Block off fuel pump on raw water pump mount and go with electric fuel pump. In reading up on this option, I would need to install a relay to turn pump on with oil pressure. Figure out a way to filter the fuel prior to moving through the pump. Install a fuel pressure regulator of some sort. Run a return hose. Is there something else I missed?
Option C: Run block mounted fuel pump with Mark IV raw water pump. Shim pump to align with other pullies as I read the Mark IV pump is not as long as the gen V.
Option D: Run block mounted fuel pump with some type of crank mounted raw water pump. Although I don't think I have any room for this type of install.
I'd prefer to keep it simple and inexpensive as possible. I'll prob just go with option A and hope for the best. Will most likely tap another hole for a second plug on the raw water pump housing to make fluid changes much easier.
SB, I have not had to deal with the fuel dilution issue so far, but I did buy the engine used and have no idea how many hours are on the raw water pump? I'm just going to use the gear lube and change it frequently for now. It would be curious to see if anyone has tried your idea though.
Thanks again
#13
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Joined: Jan 2006
Posts: 3,598
Likes: 1,168
From: taxachusetts
you want a mechanical pump,,here you go,but its pricey
https://shop.bakerengineering.com/pr...lection%20here.
holley has a pretty good one
https://www.holley.com/products/fuel...yABEgIEA_D_BwE
https://shop.bakerengineering.com/pr...lection%20here.
holley has a pretty good one
https://www.holley.com/products/fuel...yABEgIEA_D_BwE
Last edited by sutphen 30; 12-14-2025 at 08:24 PM.
#14
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Joined: Mar 2020
Posts: 845
Likes: 502
you want a mechanical pump,,here you go,but its pricey
https://shop.bakerengineering.com/pr...lection%20here.
holley has a pretty good one
https://www.holley.com/products/fuel...yABEgIEA_D_BwE
https://shop.bakerengineering.com/pr...lection%20here.
holley has a pretty good one
https://www.holley.com/products/fuel...yABEgIEA_D_BwE
#15
#16
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Joined: Oct 2000
Posts: 1,507
Likes: 589
From: Lake Ozark, MO USA
#17
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Joined: Nov 2004
Posts: 14,094
Likes: 3,684
From: On A Dirt Floor
Just saw this OEM one listed at Teague’s. Would this not work ?
https://teaguecustommarine.com/mercu...A05HTlhiNadqZs
Mercury OEM Mechanical Pump
Mounts on Mercury Racing Sea Pumps
https://teaguecustommarine.com/mercu...A05HTlhiNadqZs
Mercury OEM Mechanical Pump
Mounts on Mercury Racing Sea Pumps
- 525efi
- 565efi
- 600SCi
- 662SCi
- 700SCi
#18
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Joined: Jan 2006
Posts: 3,598
Likes: 1,168
From: taxachusetts
if your daring,you could switch the arm from your pump to the new one.
#19
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Joined: Mar 2020
Posts: 845
Likes: 502
Just saw this OEM one listed at Teague’s. Would this not work ?
https://teaguecustommarine.com/mercu...A05HTlhiNadqZs
Mercury OEM Mechanical Pump
Mounts on Mercury Racing Sea Pumps
https://teaguecustommarine.com/mercu...A05HTlhiNadqZs
Mercury OEM Mechanical Pump
Mounts on Mercury Racing Sea Pumps
- 525efi
- 565efi
- 600SCi
- 662SCi
- 700SCi
Just an interesting FYI: if you look in the tech section on Teague's sight, it shows how they run a mechanical and electric to keep fuel pressure consistent.
https://teaguecustommarine.com//medi...l_manifold.pdf
It's a shame I cannot find one of the CV billet fuel pumps that mounted to the sea pump that were around years ago.



