Good news about crank driven sea water pumps
07-09-2012, 10:29 PM
#1
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Good news about crank driven sea water pumps
Moving from pre-Alpha to Bravo required a complete re-design of my cooling system for twin SBC's. The popular favorite is the Mercruiser belt driven sea water pump that mounts on a bracket on the starboard side of the engine at about 8 o-clock. I looked at several installs with this arrangement and figured servicing that pump would be a nightmare...had to be a better way.
I have always been a fan of Marine Power and Indamar and the way they rig marine engines. I noticed that all of their rigs use a crank driven pump that mounts directly to the crank pulley. I read some old post on OSO and asked several riggers in this town about the use of this pump instead of the belt driven type that are so popular. The answer I got considered that for stock and mildly modified engines the crank driven pumps from 5 years ago and older were good choices but fell short for highly modified big block rigs. That was until about 5 years ago Johnson Pump modified their version with a larger impeller that equals or exceeds the output of the Mercruiser pumps in GPH and PSI.
So now there is no reason to prefer the Mercruiser style over the newer crank driven pumps. The new high capacity pumps are # 10-24805-01 Mod # F6B-9. This pump is offered in a kit by Michigan Motorz and Jerry's Marine that includes a torque arm bracket that bolts to the block. Servicing this thing from the front is a snap because it's right on the front of the engine....plus there is no belt to break. Not to mention these pumps retail at less than half the price of the Mercruiser pump.
This is a pic of the kit.
So I went out and bought two of these today. Suction is going to connect to the water inlet on the Bravo Transom Assembly and discharge direct to the circulating pump.
I know after reading some older OSO post that I am not the first one to do this and hope this info benefits some else facing this same question or is considering replacing their old belt driven arrangement with a simpler, easier to maintain raw water pump. If you look at the way Marine Power builds their packages you will see that all of their set ups are first class heavy duty with things like dual remote oil filters and double SS clamps on all hose connections. The fact that they use these pumps on all of their engines speaks volumes to me.
I have always been a fan of Marine Power and Indamar and the way they rig marine engines. I noticed that all of their rigs use a crank driven pump that mounts directly to the crank pulley. I read some old post on OSO and asked several riggers in this town about the use of this pump instead of the belt driven type that are so popular. The answer I got considered that for stock and mildly modified engines the crank driven pumps from 5 years ago and older were good choices but fell short for highly modified big block rigs. That was until about 5 years ago Johnson Pump modified their version with a larger impeller that equals or exceeds the output of the Mercruiser pumps in GPH and PSI.
So now there is no reason to prefer the Mercruiser style over the newer crank driven pumps. The new high capacity pumps are # 10-24805-01 Mod # F6B-9. This pump is offered in a kit by Michigan Motorz and Jerry's Marine that includes a torque arm bracket that bolts to the block. Servicing this thing from the front is a snap because it's right on the front of the engine....plus there is no belt to break. Not to mention these pumps retail at less than half the price of the Mercruiser pump.
This is a pic of the kit.
So I went out and bought two of these today. Suction is going to connect to the water inlet on the Bravo Transom Assembly and discharge direct to the circulating pump.
I know after reading some older OSO post that I am not the first one to do this and hope this info benefits some else facing this same question or is considering replacing their old belt driven arrangement with a simpler, easier to maintain raw water pump. If you look at the way Marine Power builds their packages you will see that all of their set ups are first class heavy duty with things like dual remote oil filters and double SS clamps on all hose connections. The fact that they use these pumps on all of their engines speaks volumes to me.
07-10-2012, 03:00 AM
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fixx
Moving from pre-Alpha to Bravo required a complete re-design of my cooling system for twin SBC's. The popular favorite is the Mercruiser belt driven sea water pump that mounts on a bracket on the starboard side of the engine at about 8 o-clock. I looked at several installs with this arrangement and figured servicing that pump would be a nightmare...had to be a better way.
I have always been a fan of Marine Power and Indamar and the way they rig marine engines. I noticed that all of their rigs use a crank driven pump that mounts directly to the crank pulley. I read some old post on OSO and asked several riggers in this town about the use of this pump instead of the belt driven type that are so popular. The answer I got considered that for stock and mildly modified engines the crank driven pumps from 5 years ago and older were good choices but fell short for highly modified big block rigs. That was until about 5 years ago Johnson Pump modified their version with a larger impeller that equals or exceeds the output of the Mercruiser pumps in GPH and PSI.
So now there is no reason to prefer the Mercruiser style over the newer crank driven pumps. The new high capacity pumps are # 10-24805-01 Mod # F6B-9. This pump is offered in a kit by Michigan Motorz and Jerry's Marine that includes a torque arm bracket that bolts to the block. Servicing this thing from the front is a snap because it's right on the front of the engine....plus there is no belt to break. Not to mention these pumps retail at less than half the price of the Mercruiser pump.
This is a pic of the kit.
So I went out and bought two of these today. Suction is going to connect to the water inlet on the Bravo Transom Assembly and discharge direct to the circulating pump.
I know after reading some older OSO post that I am not the first one to do this and hope this info benefits some else facing this same question or is considering replacing their old belt driven arrangement with a simpler, easier to maintain raw water pump. If you look at the way Marine Power builds their packages you will see that all of their set ups are first class heavy duty with things like dual remote oil filters and double SS clamps on all hose connections. The fact that they use these pumps on all of their engines speaks volumes to me.
I have always been a fan of Marine Power and Indamar and the way they rig marine engines. I noticed that all of their rigs use a crank driven pump that mounts directly to the crank pulley. I read some old post on OSO and asked several riggers in this town about the use of this pump instead of the belt driven type that are so popular. The answer I got considered that for stock and mildly modified engines the crank driven pumps from 5 years ago and older were good choices but fell short for highly modified big block rigs. That was until about 5 years ago Johnson Pump modified their version with a larger impeller that equals or exceeds the output of the Mercruiser pumps in GPH and PSI.
So now there is no reason to prefer the Mercruiser style over the newer crank driven pumps. The new high capacity pumps are # 10-24805-01 Mod # F6B-9. This pump is offered in a kit by Michigan Motorz and Jerry's Marine that includes a torque arm bracket that bolts to the block. Servicing this thing from the front is a snap because it's right on the front of the engine....plus there is no belt to break. Not to mention these pumps retail at less than half the price of the Mercruiser pump.
This is a pic of the kit.
So I went out and bought two of these today. Suction is going to connect to the water inlet on the Bravo Transom Assembly and discharge direct to the circulating pump.
I know after reading some older OSO post that I am not the first one to do this and hope this info benefits some else facing this same question or is considering replacing their old belt driven arrangement with a simpler, easier to maintain raw water pump. If you look at the way Marine Power builds their packages you will see that all of their set ups are first class heavy duty with things like dual remote oil filters and double SS clamps on all hose connections. The fact that they use these pumps on all of their engines speaks volumes to me.
07-10-2012, 07:43 PM
#7
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Depends on the crank pulley. If it's recessed...2~3" if not 4"~6".
Here's a 454 Indmar
[IMG]
[/IMG]
This is a 5.7 Marine Power Carbureted engine...350 Horsepower
[IMG]
[/IMG]
Here's a 454 Indmar
[IMG]
[/IMG]This is a 5.7 Marine Power Carbureted engine...350 Horsepower
[IMG]
[/IMG]
Last edited by sprink58; 07-10-2012 at 08:40 PM.
07-16-2012, 11:06 AM
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Advantage:Impeller changes in under 5 minutes. Even on the water.
Here is a shot of the Jabsco 12400-model setups on my Innovation 600's. I've been using this setup for 13 years and love it.
Here is a shot of the Jabsco 12400-model setups on my Innovation 600's. I've been using this setup for 13 years and love it.
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Retired! Boating full-time now.
Retired! Boating full-time now.
