Cummins 370 6TBA raw sea water pump

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Tomion
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Cummins 370 6TBA raw sea water pump

Post by Tomion »

Its time to replace my sea water pump impellers, they are 4 years old. Ugh! I have seen an upgrade replacement pump from Seaboard SMX 1730. They suggest on their add the stock pump is inferior and prone to failure. They are $750 compared to the stock pump of $430. Has anyone had to replace a failed pump on their Cummins 370 6BTA. My 2001 engines have 570 hour on them and about 100 hours on impellars. Thinking about putting spare pump onboard as well as impellar. Thanks
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Re: Cummins 370 6TBA raw sea water pump

Post by mjk1040 »

Are these in fresh or salt water? Your call, but I would wait until after I changed the impellers and did a visual on the pumps. If you show signs of possible failure or excessive internal wear, I would then contemplate my next move, replace with originals or upgrade them? Your $$, your call! Mike
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Re: Cummins 370 6TBA raw sea water pump

Post by Midnight Sun »

I would definitely agree. Rather rare for a pump to wear out unless the water you are in is very dirty and you have thousands of hours on the clock. 4 years and no issues, doing preventative maintenance sounds quite good and no indication of wear IMHO.
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Re: Cummins 370 6TBA raw sea water pump

Post by CYO Admin »

The Sherwood pumps are junk. I replaced mine with the ones from Seaboard and had zero issues with them.
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Re: Cummins 370 6TBA raw sea water pump

Post by Mystic144 »

Keep in mind its not the impeller that fails but rater the seal on the shaft that drives the pump.
When it fails it will take out the gears in the front of the engine.
This is what is considered complete engine failure.
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Re: Cummins 370 6TBA raw sea water pump

Post by Viper »

Mystic144 wrote:Qr Bbpost....the seal on the shaft that drives the pump.
When it fails it will take out the gears in the front of the engine.
This is what is considered complete engine failure.

+1
Replaced a Cummins 2 years ago for this very reason.
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Re: Cummins 370 6TBA raw sea water pump

Post by ScubaPete »

My Cummins 330's have the stock Sherwood pumps. The boat is a 2002 Carver 406. After 15 years and 800 hours (550+ in salt water) both are doing just fine with no leaks, drips, or weeps. All I have ever done is change the impeller every 100-150 hours.
I keep hearing that the Sherwood pumps are junk, but that's not true for me.
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Re: Cummins 370 6TBA raw sea water pump

Post by simple interest »

What is normal life expectancy for impellers when used in saltwater?
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Re: Cummins 370 6TBA raw sea water pump

Post by John Easley »

ScubaPete wrote:Qr Bbpost My Cummins 330's have the stock Sherwood pumps. The boat is a 2002 Carver 406. After 15 years and 800 hours (550+ in salt water) both are doing just fine with no leaks, drips, or weeps. All I have ever done is change the impeller every 100-150 hours.
I keep hearing that the Sherwood pumps are junk, but that's not true for me.


Agreed. I have the same engines with stock raw water pumps. The impellers are changed almost religiously at 100 hours and the 20 year old pumps are going strong. This boat has been in salt water its entire life.
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Re: Cummins 370 6TBA raw sea water pump

Post by Danv35 »

How difficult is it to change out the port impeller? Cummins 330hp 5.9
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