Leaking Raw Water Pump

[North Baltic sea]

North Baltic,
There's nothing wrong with the Seamax pumps.
I bought one when they first came out (7or 8 years?) and other than a new impeller every year, they have been stone reliable, no breakdowns or problems.
I have since installed them in 6 other boats I have worked on, no problems with them either.
I think the person who had that problem might not be entirely up front about the circumstances.
Tony Athens is a straight shooter, a very knowledgeable mechanic, and is generous with what he knows.
He personally developed the Seamax pump to replace the notoriously fickle Sherwood pumps on the Cummins B and C motors, in order to provide his customers with a reliable pump.
If you're going to spread second hand crap about him around here, there's gonna be a fight...

The aim is not to criticize anyone, I'm sorry if you got it wrong.

I tend to find things to do before purchasing decisions for web. Web can be found in a wide variety of opinions and that's why I was wondering whether this be the case, and I decided to ask it here.

I have received a lot of good Seaboard web pages and Tony's tips Cummins engines is great.

I have also read Sherwood issuing improvements to pumps, my Sherwood is run 7 yars, no leak. my mind to buy a spare pump, while it sometimes fails, so the journey continues, without the wait of the new part.

Thank you for sharing your experience seamax pump.

 

[dhays]

Do you have Cummins engines?

Yup, 5.9L QSB 380hp

 

[O C Diver]

Change the impellers every year and keep the old one for a spare (for a year). Cheap insurance.

Buy a new impeller for a spare. Next year install that impeller and buy another new one as a spare. Think about it. If the impeller goes bad out on the ocean, you then reinstall the old worn one, and finally you will need to change it again with a new one. Why would you install something that you removed because you thought it was likely to fail soon?

I keep a new spare water pump on board with the impeller removed. Install a new impeller when the pump gets put into service.

Ted

 

[ghost]

I can't tell from the picture, but which side is the pump leaking from? Sometimes the slots get dripped on from above, or are stained from a prior weep. If it's the slot in the middle with some discoloration, that is definitely the seal. If it's the face where the impeller goes, that's another kettle of fish.

If you don't have a spare pump, buy a new one. Swapping an entire pump can be done in a rocking seaway with motivation in about 15 minutes. But you would rarely have to do such a thing, though nice to know you can.

I rebuilt both of my jabsco pumps about 8 years ago. The face seals will go a month or 20 years, you just don't know. I've dealt with face seals in other applications and they are generally reliable. Same with the bearing. You likely won't wear them out in less than commercial service, and you see that large cut in the pump where it's leaking? That keeps the water that weeps from touching the bearings. Unless the thing has been leaking, gushing for awhile those bearings are often good. I replaced mine, but could have easily not done them. Replacing seals without bearings is fairly quick and simple.

The real argument for rebuilding is that you will know exactly how that pump goes together. I always recommend rebuilding for this reason, unless you don't have at least one full spare pump. My spare pump is with bracket and pulley, so I can literally swap the whole assembly with just two bolts and hose clamps.

Also, I like to run "new" pumps for awhile before swapping out to spare status. Just because something is new is no guarantee. Learned that the hard way.

Decent pumps like this, the seals and bearings can be rebuilt almost indefinitely, it's the housing and covers that can wear and determine the lifespan. I don't fear rebuild kits, in fact I trust in those. That's why you need to be 100% that the drip is from the slot, not the face. A face drip would probably just be a bad gasket, but if the impeller was putting too much pressure on the plate and caused wear, you want to notice.

Anyway, by the time you fully read this thread, you could have fully rebuilt a pump, at your leisure on a cold winter day, leaving you with a future back up. That's the best plan.