Hardin Marine stainless steel replacement for Merc seawater pump

Dream_Inn

aero3113 said:

LaRea said:

Somebody needs to figure out a way for owners to pull and replace the pulley on these pumps.  The bearings are lasting only a couple hundred hours at most, and then you have to remove the pulley and rebuild the bearings.  I have yet to find an adequate tool for it. 

@Alswagg what do you use for servicing Hardin pumps? 

Now this is where I’m stuck on the decision. Isn’t the OEM pump lasting much longer than this?

I only got 4 seasons out of my last one that I just replaced.  It was leaking at the pulley shaft.

aero3113

@Dream_Inn , was that an OEM one or Hardin?

Cableguy Greg

I bought one without a pulley a few years ago because they weren't offering it with the pulley at that time. The thing is still sitting on my boat uninstalled. Grr...

LaRea

@aero3113 yes, that's the question.  

The Hardin pump body will outlast the OEM because the Hardin has replaceable wear plates.  When Hardin's pump first came out, it seemed like a slam-dunk win.  

Since then, a decade of fleet experience has shown that the Hardin pump requires a bearing rebuild every few seasons (call it 200 hours, YMMV).  As soon as you get water dripping from the pulley shaft, it means the bearing seal has failed.  The bearing rebuild kit costs ... wait for it ... $96, and it's a real pain to install.

I still prefer the Hardin.  If I accidentally feed it a bunch of sand that chews up the wear plate, it's a 1-hour fix using parts I keep on the boat.  But you have to factor in the cost of bearing service as a planned cost. 

To be honest, with the amount of long-distance cruising I do, I should probably carry a spare pump anyway.  

Dream_Inn

aero3113 said:

@Dream_Inn , was that an OEM one or Hardin?

That was and OEM one.  I replaced it this past spring with a Hardin with pulley installed.  I installed the stbd Hardin (w/o pulley) in 2017, so it has last 3 seasons so far.  Now I'm concerned to what @LaRea mentioned.  LaRea, did it just start making squealing noises?

aero3113

So you guys would say that the bearings last longer on the Hardin pumps?

LaRea

@Dream_Inn - your pump probably has a terminal case of bearing cancer. 

In Stage 1, the symptom is a drip from the pulley shaft, indicating the inner seal has failed and sea water is getting into the bearings.  Stage 2 is a water stain under the pump (well, not for your lift-stored boat).  Stage 3 is a squeal, which means the bearings have started to corrode from water intrusion.  At that point, you have to rebuild the bearings ASAP, or risk damaging the innards.  

@aero3113 - I don't recall bearing failures on the OEMs, but that's probably because I wore out the pump bodies before the bearing seals had a chance to fail.  

LaRea

@Dream_Inn did you keep the pump you replaced?  If yes, rebuild it and keep it aboard as a spare.  

reneechris14

this is the kit he speaks of. When I changed the one on my 270 it was due to damage to the body of the pump. Scoring to deep to make pressure original pump 800hours. The two I changed last year where due to leaky seal on the pulley shaft 350 hours oem pumps. I did buy the 2 of them with no pulleys used the cheap harbor freight tool with a hose clamp so it did not break the tool or the pulley. Sand blasted the pulleys and breakets.Had to hone the pulley to get the right ID to put it back on. 

reneechris14

Black_Diamond

Hardin no longer sells the pumps less pulley to the public. I’m sure they had people damaging bearings. 

Definitely the way to go when replacing the pump IMO. 

Ian

When I did my power steering pump, same thing - HF puller was useless. Went to Autozone and made use of their tool rental and it was done before I knew it. Some of their stuff is okay but some not.

LaRea

Thanks Al, order placed.  I've been through at least five pullers with no luck whatsoever.  

aero3113

@Alswagg , would you say the Hardin pump is far superior to OEM and the way to go if you need to replace your pump?

goalie59

I have had good success with Aftermarket Marine, I have used there rebuilt kits for a while. No need to replace the pump just install their wear plates, they even have a rebuild kit for the shaft seals and bearings . I have saved a lot over the years. 

Dream_Inn

LaRea said:

@Dream_Inn did you keep the pump you replaced?  If yes, rebuild it and keep it aboard as a spare.  

Yes, I've kept it but not sure that I'd want to put it back on in place of the Hardin pump.  yes, it would work well as a backup.

aero3113

Anyone have experience with these run dry impellers?

https://www.michiganmotorz.com/mercruiser-impeller-model-2001-p-11074.html?gclid=CjwKCAiA27LvBRB0EiwAPc8XWUzi0JiskzPMt90xdB03Ggj7B4AFcOQ9-NSwGrz86p8SmDssS9Zy9RoCJb4QAvD_BwE

reneechris14

That would fit in the hardin pump but not the OEM.  OEM has 2 flat spots. 

Dream_Inn

Very interesting aero!  I'm not sure it's worth double the price though, especially if you replace them every other year. But I have seen some people (on lifts particularly) that have issues with priming that maybe this would help.

aero3113

Its possible this impeller doesn't have to be changed every other year, it might be worth the extra money if that's the case. It looks/sounds like this material is softer and doesn't get brittle and wear like the originals. I think when I get the harden pumps Ill run them for 2 seasons then replace with these. The south shore of long Island is all sand.

aero3113

Defender has them for $49.99. They also make them for the OEM pump.

https://www.defender.com/product.jsp?path=-1%7C51%7C2234245%7C2234249&id=1041144

aero3113

$72.99 for the OEM pump

https://search.defender.com/?expression=2002+impeller

aero3113

Probably have one for the generator also.

skuter99

Regarding replacement time for impeller, I have mag 350mpi with hardin ss pump.

first season June till October, second season May till October, should I be looking at impeller replacement this year, or am I good for one more season?

Thanks

LaRea

A common "best practice" is to replace after 2-3 seasons, even if there are no symptoms.  

Glassguy54

A good friend of ours had a Formula 280 Sun Sport with twin 350 Mercruisers and he told me he never had the impellers replaced. I was kind of taken aback, because where he kept it (local reservoir) was shallow, muddy & sandy. Go figure.

Black_Diamond

I never go more than 3 seasons. Personally every 2 seasons, just not worth the hassle and always bad timing if the impeller fails. 

LaRea

Replacing impellers ... another method of manufacturing good luck.  

skuter99

Thanks

earl1z19

I think the Merc recommendation is 150 hours so in most cases its 3 years. I know the pump is Hardin but the impeller is Merc so I would go with that time frame.