Northern Lights 5 KW Generators

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HiDHo

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Has anyone tried the run dry type raw water impellers (Globe Composite Solutions) to replace the NL #25-12009 impeller. I have had the NL impellers last any where from 100 to 300 hours.
The one in the photo had 117 hours of use.
 

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That looks a bit scary. I just replaced mine with a Jabsco but was going to use the NL impeller the next time. Now I am not so sure.
 
Any idea why so quick to fail?

Even intermittent use most of my impellers on mains, gas engines, gensets all last year's and at least 200 to 40 hours of service. Probably more but get changes before failure.
 
I have found on gensets over the years is some lose raw water as they sit and the impellers start up dry. Depends on the install height above the water line. Another thing I recently experienced is new boxed but old impellers time wise can break up.
 
My NL pump sets below the water line so I don't think dry runs are the cause. My Volvo TMD 31 A impellers go for 700 to 800 hours, I use Johnson Pump impellers.
I thought maybe I got old setting on the shelf impellers but the NL # 25-12009 seems to be used in several of their generators so there should be a turn over of inventory.
I was hoping someone had cross referenced the impeller to another supplier or was trying out the nitrile impellers vs neoprene.
 
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Just curious - how old was it, as opposed to the number of run hours? I never count on them running for more than a year unless the boat is used regularly over the course of the year. And then I don't think I'd push it for more than 2 years.
 
351 days. I pull the cover each year and inspect impellers, just seems like the NL eats them up fast compared to my Volvo impellers that last several years. In my generator spares I have a new NL # 25-12009, labels says made in Italy the one in the photo was labeled made in the USA. I think neoprene has a long shelf life if not exposed to heat, sunlight.
This 5 KW generator pump puts out a lot of water thru the exhaust, could be the design of the pump which might account for the short life of the impellers.
I also have read on other forums about the problem of short life of these impellers.
 
Has anyone tried the run dry type raw water impellers (Globe Composite Solutions) to replace the NL #25-12009 impeller. I have had the NL impellers last any where from 100 to 300 hours.
The one in the photo had 117 hours of use.

It is not normal for an impeller to fail that quickly.
 
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Replace the water pump with an electric pump.
 
Should be a Johnson pump, might source impellers directly from them. I too find that impellers that have sat for years in stock tend to die early. Also if inside of pump bore is rough or has sharp edges on cam, that can eat impeller too.

I also have a NL 5kW with the old skool pump with lip seals, I have changed the seal more times than the impeller. Probably three impellers in 2000hrs and eight years. More modern units have the lip type seal which is much better, but the bigger impeller tends to move lots more water.
 
My NL 8Kw gen has about 350 hrs on it and the original impeller. It pumps well but it's 5 years old now so I'm changing it. It just so happens that the impeller in this gen is the same as my FL 135's - Jabsco 1210-0001P. Your NL 25-12009 is the same as a Jabsco 18673-0001. Maybe one of theirs will have a better life?

Ken
 
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My NL 5KW has the same pump and I've been using the Johnson impellers that came with the boat, wrapped in a sealed plastic bag. With the original pump I kept having to replace the ceramic seal. According to the log, I got 100, 130 and 140 hrs. out of the three replaced impellers, then replaced the shaft and solved the seal problem. When I moved the unit to a new hatch under the veranda, I rebuilt the whole genset and installed a complete new pump, rebuilt the old one, then pickled it for a spare. So far, zero hours on the recon. At least one Manatee out there is using a March A/C pump in place of the old Johnson unit. I might even consider that but having to replace my own March A/C pump three times in four years with low usage, I don't find it any more reliable than the Johnson.
 
Impellers that look like the OP are not uncommon.

The hassle is finding all the pieces that shed and may now be pluging the block or heat exchanger.

Much UNFUN.

For cruisers the simple precaution of installing a 1 inch Y filter from Sendure mfg will catch all the bits and pieces , and cleans out easily.

Another concept is to replace all the tiny screws that hold the cover plate on with cap screws.

These will allow the removal tool to work , no silly slot to find and maintain while unscrewing , usually blind..
 
Thanks Kchase and Larry I will try the Jabsco impeller. My NL I has 962 hours on it so I'll hold off on doing the electric pump mod. I'm also going to double check the things Ski in NC pointed out just in case something is tearing up the vanes in the pump housing.
FF, finding the missing impeller pieces on the NL is not difficult, just remove the fan belt guard and remove a rubber boot on the cooler header and assemble the jig saw puzzle of vane parts. Someone at NL was thinking about maintenance when they designed it.
 
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I'm just going to reiterate what Ski said. Any sharp edges on the cam could cut the impeller up in short order. Same for any roughness in the pump housing.

I replaced my r..w. pump cam a few years ago. The impeller was not being chewed , YET, but the leading edge of the cam was getting thin and close to sharp. Although slow wearing , they do wear.
 
I replace mine every year (NL) and typically has over 100 hours a season and looks brand new each time.
 
HDH

How many hours on the pump?
 
I replace mine every year (NL) and typically has over 100 hours a season and looks brand new each time.

I replaced the impeller on my 56hp Yanmar yearly on the sailboat. It typically had much fewer hours on the engine than most of your Gensets do. These impellers don't seem terribly expensive and are very easy to replace. Doing it yearly seems like easy preventive maintenance. Of course if your Genset hours get up there, doing it even more often might be prudent.

Question though... I used a Jabsco impeller to replace mine last week. The Jabsco that I got fit great, but did not come with a replacement O-ring. That made me consider using a NL impeller for replacements in the future.
 
Question though... I used a Jabsco impeller to replace mine last week. The Jabsco that I got fit great, but did not come with a replacement O-ring. That made me consider using a NL impeller for replacements in the future.

At least up to now, the O-ring came with each Johnson or NL kit I've used, but I did re-use one O-ring when I dropped the new one somewhere. It leaked.
 
X2 on checking the cam. Very easy to check and replace.
 

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