Northern Lights Raw Water Pump

[Bustlebomb]

I recently posted about a raw water pump on my generator and got some great input on how to repair (thanks to all who helped!). One of the suggestions was to buy a new one and rebuild the old one so I've got a spare.

In looking at buying a replacement pump, I see the Northern Lights part (25-12007) which appears to be made by Jabsco. I also see that JMP makes a replacement pump as well. The JMP pump is 1/2 the price but I've never heard of JMP. Online reviews seem positive but I trust this forum more.

Does anyone have experience with JMP pumps?

Thanks,

 

[tiltrider1]

I don’t have any experience with JMP but since you plan to rebuild your OEM as a spare I think it’s safe to take a chance on the JMP.

 

[bayview]

never buy oem if you ca avoid it. Check Depco pump for pricing as well.

depcopump.com

 

[Comodave]

Depco may be able to give you some feedback on that pump. I have never heard of it but that isn’t surprising...

 

[sunchaser]

Johnson Marine Pumps. Lots of them in use as replacement and OEM.

 

[Simi 60]

.

Does anyone have experience with JMP pumps?

Thanks,

I have a JMP raw water pump on my 855 Cummins for two years now and the Jabsco relegated as a spare.


I am happy with it especially as the JMP was less coin and came with the pulley and large hose tails already on, so a straight swap.

Replacement jabsco was bare so even more expense to get it to work.

 

[Simi 60]

Johnson Marine Pumps. Lots of them in use as replacement and OEM.

Don't think so
JMP are made in Korea since 1977

http://jmp.co.kr/

 

[Simi 60]

But, for a fixed rpm genset, there is no way in hell I would EVER go back to impeller.
Electric pump all the way.

Details on pump we used here
Near 1000 hours on it, far better than the original
https://www.trawlerforum.com/forums/showpost.php?p=938875&postcount=15

 

[Larry M]

Just my suggestion, but I’d put the rebuilt one after you have it rebuilt. That way you know it works and you have a new spare. We’ve had 2 NL generators over the last 20 plus years and have had horrible success with rebuilding them myself and by professional rebuilders. The seals are hard to seat perfectly on a worn shaft. There’s nothing worse than using a rebuilt part that hasn’t been tested that doesn’t work or fails quickly.

You could also go with an electric that Semi 60 suggested. They aren’t self priming so they need to be below the water line but for reliability they are hard to beat.

 

[Bustlebomb]

Larry,

You bring up a great point about the rebuilt one.

Simi,

That's an interesting option. The way it is set up now, the raw water pump starts pushing water as I am cranking the generator. With your set up, the generator starts with no water flowing since your pump doesn't start working until it has electricity. Do you run it directly off of the generator so as soon as it fires up, the pump starts working? How would I determine what size pump (how many gpm) is needed by my generator?

Thanks,

 

[Simi 60]

With your set up, the generator starts with no water flowing since your pump doesn't start working until it has electricity. Do you run it directly off of the generator so as soon as it fires up, the pump starts working? ,

I run it directly off of the generator so as soon as it fires up, the pump starts working.

How would I determine what size pump (how many gpm) is needed by my generator?

Thanks

Many seemed to go with March electric - too expensive here
Others used pumps designed for home brew
All seem to pump around the 20 to 30 litre/minute
There are plenty of threads from US owners on here or cruisers forum
Fill your boots (-;
https://www.google.com/search?newwi...HVbPDjIQBSgAegQIARAC&biw=854&bih=1280&dpr=1.5

 

[Anniesez]

I recently replaced the raw water pump in my NL 753G with a JMP pump. Appears to be a robust pump. Too early to tell for service life.

 

[sunchaser]

IMHO

Personally I'm not a fan of electric driven raw water pumps for gensets unless some design issues have been addressed. For instance, establishing required flow rate for the installed piping, exhaust run and muffler. Back flooding the genset with incorrect pump size is an obvious no no. Then nailing down circuit design to preclude pump from running when diesel isn't running. Then the additional amps required yada yada.

With the engine driven raw water pumps not expensive and very long lasting if treated right the risk reward doesn't seem to balance out. For sure a new genset warranty would be voided by eliminating OEM raw water design.

 

[Simi 60]

IMHO

Personally I'm not a fan of electric driven raw water pumps for gensets unless some design issues have been addressed. For instance, establishing required flow rate for the installed piping, exhaust run and muffler. Back flooding the genset with incorrect pump size is an obvious no no.

Have not heard of anyone having that issue - have you?

Then nailing down circuit design to preclude pump from running when diesel isn't running.

Its wired directly to the genset - genset not running means no power to pump
Easy

Then the additional amps required yada yada.

The additional one amp?
I reckon a genset can handle that.

With the engine driven raw water pumps not expensive and very long lasting if treated right

. Its the short lived impellers at $40 a pop and the bloodletting required to change.
Also, a replacement Sherwood pump landed in Australia is over $1000
https://shop.toadmarinesupply.com/ships_store/?p=details&mfc=Universal&sku=302837&sectionid=5171

the risk reward doesn't seem to balance out

Sure it does, I see zero risk and all reward

For sure a new genset warranty would be voided by eliminating OEM raw water design.

No one is advocating taking off a new, perfectly good pump.
Its owners who's pump has died and needs replacement , so clearly an out of warranty genset

 

[Xsbank]

The fuel pump is electric, tee into that.

 

[ksanders]

I have over a thousand hours on my NL raw water pump with only one or two impeller changes.

Why not just replace the pump you have with the same unit? If jabsco made it, just buy the same thing, Jabsco branded and be done with it.

 

[Simi 60]

I have over a thousand hours on my NL raw water pump with only one or two impeller changes.

Why not just replace the pump you have with the same unit? If jabsco made it, just buy the same thing, Jabsco branded and be done with it.

Possibly because they are 6x the price of the electric alternative
Then $50 every time an impeller goes
And $300 for a rebuild kit

Compare that to $100 for electric and there the story, price gouge and labour ends.
Time and money saved spent on more important things like single malt speyside whiskey and time to enjoy it. (-;

 

[Bustlebomb]

Thanks for all the input.

Looks like the JMP may be a viable option quality-wise.

I’ve got to go down and do a little wire chasing to see what I need to do if I decide to go with the 110v pump.

Simi, what did you use for circuit protection?

 

[Larry M]

I added to the TF Library under Systems, a file where an electric fuel pump was added to a Northern Lights generator.

https://www.trawlerforum.com/forums/downloads.php?do=file&id=127

 

[Simi 60]

.

Simi, what did you use for circuit protection?

Cut the plug off one of these and connected directly
Plug pump into it

 

[Bustlebomb]

Larry, that's perfect. Thanks!

Simi, great idea. I'll see what I can find that is similar to that, but 110v.

 

[Duetto]

we have 110v pumps on gensets on 2 different boats. one has 1700hrs and the other 600hrs. as simi said wire right to genset output. only thing that took some thinking was that on our mainship pilot the bilge in rear is near waterline and led to air in line downstream from pump. if install is at least 6-9" below water line you shouldn't have a problem.

 

[Salish Nomad]

I recently replaced the original pump on my 6KW generator with a JMP pump. The oe pump was not repairable due to corrosion on the ss shaft beneath the seal.
The new pump looks to be excellent quality.

 

[Carolena]

FYI - we replaced the raw water pump on our NL generator a few months ago. From what I could tell, it looks like JMP supplies the pump for NL on our genny. We went with the JMP and the only difference I could see looking at the pump was no NL logo embossed in the impeller cover plate. We shopped around and got the JMP for less than half the cost of the NL replacement, and not much more than a full rebuild kit. That plus the time and tools needed to rebuild, it made more sense to buy the JMP. One season in and we are happy so far.

 

[Xsbank]

How much is a N.L. Pump? I have one that is a paperweight that was a spare on my 8kw genset on my old GB.

It's heavy so shipping might be spendy but I would love to see it go to a happy home.

I'll post pictures as soon as Apple gets it together.

 

[Xsbank]

Sorry, here it is: