Jabsco Raw Water Impeller Pump Shaft Seal Leaks

[sdowney717]

I have continual issues with my 3 jabsco salt water pumps
one is electric, the others are engine driven.
Compared to the Onan raw water impeller pump on the generator which has never leaked since I owned the boat over 10 years.

I have cut open those brass seals with the black carbon insert and I know why they start leaking. Salt water corrodes the inside where the small thin oring seals the carbon ring to the housing. Then the carbon ring gets stuck and no longer seals against the white ceramic face. The brass seal insert has a spring that pushes on the black carbon seal face.
A slight improvement I found was to remove the bronze ring on the shaft behind the white ceramic seat and put a silicone rubber ring. That ring acts like a spring and in effect pushes the white ceramic seal against the non functional black carbon brass seal.

So does anyone else have pumps like this that leak all the time and need expensive new seals every few months? I half believe jabsco likes this because people have to keep on buying new shaft seals.

[St. Elsewhere]

I had an electric driven water pump">raw water pump that was a maintenance headache until I replaced it with a magnetic drive pump. The weak point is the stainless shaft from the motor. Stagnant sea water causes the shaft to corrode which results in shaft seal failures. The magnetic drive eliminates the shaft and therefore the problem. I don't know what to do about an engine driven situation. More info is here: Magnetic Drive Pumps - Wikipedia, the free encyclopedia

[HopCar]

The ceramic / carbon face seals should out last several impellers.
Do your seals have a coil spring in the carbon half or do they use a wave washer to push the carbon against the ceramic?
What is the model of the pumps?

[sdowney717]

coil spring is inside the carbon half and comes as a sealed unit.
The carbon half gets stuck cant move then it starts leaking cause it looses its pressure against the ceramic white half

price is 39$ as you can see here. this seal is used in many jabsco pumps
http://www.go2marine.com/product.do?no=48223F

After you own something a few years and have so many leaks occur, you start to think of using a different manufacturer but the pumps are very pricey.

The engine has 2 pumps that use these seals, raw water and coolant recirculating. And I have two engines.
The coolant pumps with antifreeze almost never leak and are pretty trouble free.
The raw salt water ones always do after a while due to corrosion issues inside the seal.

The other leaky jabsco pump is an electric one which sees very seldom use, but even using a new seal, you can bet every time you start it it will leak drip etc... from the shaft weep slots.

[HopCar]

I can save you a few dollars on the seals but they shouldn't fail that fast. I sent a note to a friend of mine at Jabsco and asked her to check with their engineers to see if they have any ideas. I'll let you know what I find out.

[delmarrey]

I would think for marine application the springs/parts would be made of Inconel®, or at least 316L. They should not rust. You may be getting the wrong part # (for fresh water applications). Lets see what HopCar comes up with.

717, can you supply us with a pump Model #? Pictures ARE worth a thousand words.

[sdowney717]

5330 bronze pumps
Jabsco 5330-9101 Flexible Impeller Pedestal Pump

As far as I can tell, the spring does not corrode, the carbon seal gets stuck and cant move because the bronze seal housing corrodes. the way these work construction wise is
you have a bronze or brass outer case.
the spring goes in first
then the carbon face with a slim rubber oring on the outer edge of the carbon seal goes into the brass seal housing.
the lip of the seal housing is peened over to retain the carbon face seal.
when corrosion gets into the metal seal housing, the rubber ring cant slide or roll and the carbon face seal wont move and seal against the white ceramic seal.



you can decide to tolerate dribbling out of the weep slots but then you have salt water spraying dribbling on your metal causes a lot of rusting.

the jabsco seal years ago used to use an external spring but the new seals the spring is inside the seal.
as a way to try to help my situation, I pulled off the bronze spacer ring from the white ceramic side and replaced with a silicone rubber ring to act as a spring, pushing the ceramic seal against the brass carbon side and this gets me some more time. but eventually that also will fail either to rubber hardening or perhaps the carbon face wears down.

picture of the seal. The indentations keep the carbon face seal from rotating in the outer brass housing
http://www.fairfieldsupply.com/servl...80-0080/Detail

[sdowney717]

as a comparison with a pump that works extrmely well in the same boat is the mcck Onan generator pump here. I dont even know how there seal is designed, never had to open it up.
I took it off to replace the impellor and take a picture for you. This pump has never leaked on me.

[HopCar]

sdowney717, I received a note from an engineer at Jabsco. He wants to know what is being pumped, the model of the pump, and the duty cycle.
I assume you are pumping salt water, the pump is a 5330-9101, and the duty cycle is continous. These are your engine cooling pumps? That Onan pump is probably made by Jabsco as well. What model onan is your generator?

[HopCar]

sdowney717, I'm going to send you an email or PM with the contact information of Keith Evans at Jabsco. He is their product manager of flexible impeller pumps. Please keep me in the loop. I'd like to know how this works out.

[sdowney717]

I assume you are pumping salt water,

yes

the pump is a 5330-9101, and the duty cycle is continous. These are your engine cooling pumps?

yes. The pumps could be original to the boat which is a 1970 eggharbor with palmer IH 392 engines. (The pump bearings are not worn out)

That Onan pump is probably made by Jabsco as well. What model onan is your generator?

mcck 6500 watt, 120 volt, single phase 1800 rpm from 1970 with control -o- matic
I will add that it works great , I do try to keep up the equipment.

here is my manual online
Onan MCCK Manual

palmer engine manual
http://www.docstoc.com/docs/34445237...04-IH345-IH392
manual for the boat
http://www.docstoc.com/docs/34446278...or-Boat-Manual

the coolant pumps are 8500F 8510 F and work fine due to no salt water running threw them.

the electric jabsco salt water pump is like this one here and also leaks.
that price is crazy. Mine came with the boat. Might use a lip seal, this one I dont have so much concern as it is not used much at all.
http://www.boatersworld.com/product/MP63508984.htm
http://www.pumpvendor.com/media/jabs...050_series.pdf

seeing the price makes me think of fixing and selling it. what is a used one of those worth?

[HopCar]

Did you get the contact info I sent you? If the pumps are more than forty years old it might just be time to replace them.
The electric pump could be that old as well. They've been making them forever.
Here is what we sell them for: 1" NPT 115V AC Motor Pump - 6050-0003
Used value might be half of that.

[Mark Zarley]

The Onan pump has a lip seal I am pretty sure. The raw water seals on the engs were probably lip seals also because of the year of manufactor. Jabsco has probably updated the seals but the pump casting has not changed. I would try to get the original lip seal number and install. Some up dates just do not work out. In defense of the mechanical seals I have them on my NL genset and get around 1700 hrs before they start dripping.

[sdowney717]

this is the original old, so very very old instructions for the pump.
If you notice the spring was external to the seal. likely worked better as today the spring is inside the brass housing.
still was a type of face seal.
and no I did not get any message.

[delmarrey]

It would be nice if you could greatly lubricate the o-ring with lithium grease but the carbon seal must remain clean or it will not seat.

Personally, I think I would retrofit for different pumps. Salt water around hot steel parts is a major problem on boats, which makes them difficult to work on let alone the cosmetic aspects.

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