Hardin Gen 7 Plus Seawater / Impeller Pumps

TonyG13

Just resurrecting the topic since it is now time for me to do some replacing. My shaft seals are leaking. I've read all the past topics and have a pretty good idea about them but does anyone have any real world experience on the Hardin Gen 7 Plus series since we last discussed in 2023-2024? Such as longevity and value compared to OEM?

My mechanic said he can make the switch while in the water - but that makes me a bit nervous. Anybody swap a pump while in the water?

I know @LaRea was the resident expert on rebuilding these Hardins but has moved on to bigger and better things! 

LaRea

He'll be fine swapping with the boat in the water.  Disconnect the supply hose, use a screwdriver to stuff a rag into the hose.  Might end up with a quart or two of water in the bilge when he's done.

Dream_Inn

I swapped mine out while on our 10 day trip in August.  My point is, I wasn’t home on my lift, so I did it in the water.  Like Chris said, just lift the hose above the water line.  I need to rebuild my spare Hardin this winter. @LaRea , any tricks to the press?

aero3113

I did mine in the water a couple times, I stuck a wooden tapered plug in the hose. 

oscar1

I just did mine in a trailer, it took a day to get it done, I am glad i didn't do it in the water. I have zero room to work in my eng bay, so everything take longer. 

TonyG13

Thanks for the quick responses. I'll probably order them this week.

I think I'll have him do both engines since they're the same age - and it saves a trip.

@oscar1 - As you know we have the exact same year and model - and the zero room in the engine bay is exactly why I'll have the mechanic do it. I'm getting too old to move quickly down there if something goes wrong.

LaRea

@Dream_Inn - Getting the bearings off and on with the press is straightforward, but the seals can be a pain.  To get the old seals out of the pump body, you might need a piece of steel rod with a slight bend in the middle so you can hammer them out.  When pressing in the new seals, be careful to keep them aligned or they'll go sideways and ruin the seal.  I was using a deepwell socket to press them in.  

Do you have snap ring pliers?  I bought a cheap set for $35 ... they worked but a nicer set would be easier to use.  

YYZRC

I still don’t understand what makes the Hardin “better” (apart from them being shiny). I am quick to throw boat bucks around but these pumps are one trap I am so happy I didn’t fall into. 

TonyG13

YYZRC said:

I still don’t understand what makes the Hardin “better” (apart from them being shiny). I am quick to throw boat bucks around but these pumps are one trap I am so happy I didn’t fall into. 

What's the trap? For my set-up -- 350 MAG Seacore MPI Bravo ECT with Axius -- Mercruiser (original OEM, not an Amazon or eBay knockoff) would run me north of $700 while the Hardin is about $600 all in. 

That +$100 can go into the annual fuel kitty.

oscar1

I installed original OEM.

LaRea

The "better" is replaceable wear plates.  When the inside of the pump body gets worn from ingesting sand or whatever, you can replace cheap wear plates instead of buying a new pump.  

Hardin's original pumps were great, except the bearings and seals didn't last long enough.  The "Plus" models have bigger, stronger bearings and seals.  The question is -- do they actually last longer?  (I never owned one, so I don't know.)  

YYZRC

LaRea said:

The "better" is replaceable wear plates.  When the inside of the pump body gets worn from ingesting sand or whatever, you can replace cheap wear plates instead of buying a new pump.  

Hardin's original pumps were great, except the bearings and seals didn't last long enough.  The "Plus" models have bigger, stronger bearings and seals.  The question is -- do they actually last longer?  (I never owned one, so I don't know.)  

Understood on the wear plate, altho the OEM pump has a wear plate on one side. 

So back to Tony’s issue. Bearings due to be replaced. I had a new bearing put in a spare OEM pump for $50 CAD. I don’t understand why you would replace a $700 pump because of a failed $50 bearing/seal. 

TonyG13

@YYZRC - OK, that makes sense. I'd say I'm probably in the bottom 1/3 of mechanical knowledge of users on this forum - and still learning. Even when I was a kid I could do carpentry, plumbing, electrical, etc., but for some reason never grasped internal combustion engines. Probably why I was a facilities manager supervising building things for 20+ years but never a mechanic.

Since owning this boat I have learned to swap out cool fuel filters and change the oil, but am still a bit apprehensive when it come to things that could sink it if something go wrong! I rely heavily here on this forum for the local knowledge to keep her shipshape - and you all come through in that regards. Thank you!

That said, I also have two local (good) mechanics who I use, but since they are good it is hard to get ahold of them and schedule them. (I'm still waiting for one to call me back about the shaft seal.) Maybe they will tell me to just install a new bearing/seal. But can you even do a bearing/seal dockside or do you need a bench with specialty tools? If he can do that for $50 plus whatever time and materials that would be great.

I guess I was just thinking about the easiest way to just do a whole unit swap and be back on the water the fastest.

YYZRC

I boat with a toddler, an infant and a pre-teen. Everything I do is through the lens of will this make my boat safer, more reliable, or perform better. That’s why I copy almost everything @aero3113 does because he also has young kids. 

All that said, I just don’t understand the appeal. The only benefit of the Hardin that I can discern is that you can replace the wear plate af the base of the impeller shaft. How many hours before you would need a new OEM pump because of wear in the same location? 1000? My previous Rinker had 500 hours and the pumps were barely scored at the shaft base. This also isn’t something that fails suddenly, leaving you stranded. 

OEM pumps I can get parts for at any Merc dealer (and usually in stock). Hardin? Ship the whole pump assembly back and wait. Expensive and time consuming - especially if you can’t remove the pump yourself (it’s a terrible job if you are more than 75 pounds and 48” tall). 

I am convinced that if we got John and Chris a bit tipsy, they would admit that the Hardin were more trouble than they were worth!

aero3113

@YYZRC 👍🏻👍🏻

LaRea

Pumps might last 1000 hours, but you can definitely destroy one in minutes by pumping a bunch of sand through it. 

For me, boating in the silty, shallow Potomac River, wear plates were a big deal.  That dang silt destroyed several of the disposable OEM pumps.  The pump body would wear, I'd get overheat alarms when coming down off plane, and I'd shell out $1500 for new pumps.  Once I switched to the Hardins, I just had to replace the wear plates every other year when I did impellers.

But, of course, the Hardin seals and bearings didn't hold up.  Did I come out ahead compared to OEM?  Maybe, but it sure wasn't the slam-dunk I hoped for.  

If you don't feed your pumps a regular diet of sand and silt, maybe pump wear isn't a factor. Count yourself lucky!  

Dream_Inn

I agree with Chris (you say, well of course), because I got thru lots of sandy areas.  Just today, at low tide, my radar touched the dang bridge to go under to get back to my marina.  I had to turn around and go the ‘back’ way.  It is pure sand and when I can’t get under the bridge, it is maybe 2-3 feet depending on tide.  Today since I knew it was low because another 1/4 inch down I would’ve made it under the bridge, it was going to be shallow.  I turned the boat off, put drives up and pushed her thru, with admiral hitting bow thruster once in a while to steer.  The point is I have sandy areas that wear out those pumps.  

And, yes you can buy parts just like the OEM to fix it.  Also, it really depends on the boat for how easy or difficult it is to change.  I can do mine in under an hour, including taking apart, installing impeller and plates. I’m extremely lucky with all the space I have in my engine room.  But, I’ve owned the 240 and 310, so I know.

aero3113

Agree, having room really helps. I love the space my 330 has in the engine compartment.

TonyG13

Well I guess I will be the Guinea pig for the Gen 7 Plus.

I found a guy who was selling his boat and the new owner wanted all OEM so he swapped out his newly (10 hours) installed Hardin back to Quicksilver. So I got it with an extra (new) impeller, plates, adhesive, and stainless bolts for $400.

Plan is to install the Hardin and then rebuild the OEM for future use if/when needed.

I'll keep everyone posted as to the long-term success/failure. 

Corral42

I replaced both with hardin last season. Fun job.

rasbury

Omg I wish my motor looked that clean! So, seems like I recall me mentioning ware plates with a special impeller (100$) was just crazy talk and I should sign up for the harden pump!
Florida boating for sure is sandy shallow water. Our boat came out of the panhandle with 50 hours (showing) and soon I was learning about water pumps. I think if the seal is leaking then I'm out- I don't have a press for seals and such- or experience so I'd go new at that point. Our boat had around 375 hours before the gauges were stolen- I'm certainly over due for impeller replacement.

rasbury

@Corral42, not to hijack the thread, how the heck is your bilge that clean for an 07 boat? Lol

Corral42

The fire extinguisher could use some freshening up

rasbury

Corral42 said:

The fire extinguisher could use some freshening up

It looks like your bilge was painted at some point? I was at ours yesterday pulling a battery- it's like a petri dish down there. I also have water in the mid ship bilege (1/4") , should that not drain on through to the back? I think it's the anchor locker taking on water (rain, I'm on a trailer)...inside is dry with no musty smell.