I would use the Hardin pump over stock on the 496.

I ran one for 9 years till I sold the boat. I changed the impeller every year as annual maintenance. I kept reading how guys would go seasons on the same impeller. I skipped changing the impeller one year, to have sea water get into the bearing. I went back to changing the impeller at the beginning of every season.

What's nice about the Hardin pump is you can change the bearings and seals. I always kept an impeller kit and a rebuilt kit(impeller/seal/bearing) on the shelf. You can rebuild the pump in minutes if needed.

The newer style Hardin pump has double bearings and seals in it. The bearings are larger as well. A nice design.

Interesting, I'll ask my friend if his has the new dual seals. Seems like it should he had another one start leaking right before the toy run and had to replace it.

Pretty sure I will see him today for the games.Makes me glad I have the old plastic cheap bravo pumps, easy to change the whole thing every time.

Yeah, the OEM brass Merc Gen 7 pumps list at $605.00.
Seen some at $475 ish.
And of course Chinese imposters on Ebay for $200 ish.

So, the Hardin make sense if there are no issues.

I run the Hardin pumps. No issue if mounted with the right bracket.

i had initially used the snout mount style and chewed up bearings. Once the Hardin team told me that was my problem, no issue since. Change impellers every spring - cheap peace of mind.

not sure why you’d re-design water flow on a stock 496. Plenty of cooling power in the Bravo setup. Hell, I run closed cooling on 800HP 565’s with the standard bravo pump and never have temp move off 150*.

I would block off the exhaust and go straight thru-hull but that’s just me. Makes life simpler.

Just got back from talking with my buddy.

I had my numbers wrong.

He has had two of the Gen 7 pumps leak and one gen7 plus leak. Hardin covered them but he has had to pay for shipping to and back to them.

About 10 hours on the gen 7 and made it 20 on the plus.

The last time he got pretty irate with them and they paid the shipping on the gen 7 plus.

Not sure on the hours now, pretty much the 3 days we ran in the toy run, I forget how many hours we ran.

all have leaked not bearing failure.

seafordguy,

what was your issue? Maybe he needs to look into the same thing. 2006 Donzi ZR.

I'd seen several posts on forums, (can't remember if it was here or others at the moment) where people were complaining that there is a common issue where 496's will go into guardian mode under acceleration because the water pressure drops below 7psi and even though theres plenty of cooling capacity, its doing it because it thinks its protecting the engine from an overheat... I think it also doesn't give you any codes to boot so its a very frustrating problem if you don't know about it.

My issue was the snout mount style. It was ever so slightly distorting the snout when I clamped it down. Once I switched to the face mounts I haven’t had any problems since. I was frustrated with the rebuild cost. It was almost as much as the pump and one time I just bought a new pump so I think I have an extra over at the garage.

Got it. My boat is old school.

Yea, this is my first boat with fuel injection and computers... Not sure how I feel about it lol.

Is the water pressure sensor mechanical or electrical? Its seems 496's always have sensor issues, there's a lot of electronics on that engine. My buddy had a couple back a few years ago and every issue he ever had was due to some kind of sensor