Jabsco Raw Water Impeller Pump Shaft Seal Leaks

[sdowney717]

yes the grease idea would be nice. See with this seal, water gets into the inner ring of the shaft hole, between carbon face and seal housing, goes behind the carbon face where the spring is, The rubber o ring is one the outer edge and stops the water moving further. But putting lithium lube behind there would take an extremely small needle. It would be better to drill a small hole on the seal backside, tin with solder, fill it with grease, then perhaps solder it shut.
Lithium grease and water dont mix. Actually this idea has some merit.

All the failed seals, the carbon ring is intact, it just looses the ability to press against the ceramic face so it dribbles. I can get a summer's worth out of the seal, BUT IMO, it should last much longer seeing the carbon face does not wear down hardly at all.

You cant just push the seal further into the housing, it needs a spring pressure to allow movement, without that it wont work, you will break the carbon seal or massive wear and then leaks again.

[HopCar]

sdowney717, This is the important part of the message I sent you.

Send Keith Evans an email about your seal problem.
Keith M. Evans
Product Manager
Flexible Impeller
ITT CORPORATION
keith.evans2@itt.com


There are tens of thousands of pumps with this type of seal in service. I've been selling them for about forty years. There is nothing wrong with the design of the pump or seal. They normally last hundreds of hours before the seals need replacing. There may be a bad batch of seals out there or you may have something wrong with your forty year old pumps.

"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."

These pumps lasted forty years. That's pretty damn good. They are still selling the exact same pump. I think I'd buy the same pump and then worry about it in forty years.

Come to think of it, you mentioned earlier that the bearings weren't worn out. That doesn't sound normal for a forty year old pump. If the bearing is worn, it could allow the shaft to get out of alignment which would let water into the seal.

[sdowney717]

ok , perhaps it is possible the bearings are loose. They feel decent to me.
A prior owner may have put in new bearings, I owned the boat the last 12 years, so what about the prior decades.

The bronze pump body is in excellent shape.
Of course the manufacturer will never say anything negative.

"which would let water into the seal"

the seals are designed to get wet on the inside. Water passes up the shaft into the seal by way of the seal center hole. It is then retained by the ceramic face seal on one side (which has its own o ring to seal to shaft) , and on the carbon side by the internal rubber oring. The backside of the carbon face seal and spring and metal housing are salt water saturated on the inside of the brass bronze seal housing.
I can replace the seals and I get a year out of them. I think they should last longer. But you dont understand how these work or you would not have said that.

[HopCar]

Sorry I didn't make my self clear. The problem wouldn't be corrosion in the spring housing, it would be corrosion in front of the carbon seal preventing the spring from pushing the carbon forward as it wears. Of course water isn't supposed to get on that side of the carbon so maybe the seal starts to leak before you get corrosion there. Now I am confused!

I'm not familiar with your Palmer engine but I'm assuming that the pump is belt driven. If so, remove the belt and try to push the pulley to the side. If you can't detect any movement it probably isn't the bearing.

"So does anyone else have pumps like this that leak all the time and need expensive new seals every few months?"

In my experience very few people have this problem. You should contact Keith at Jabsco and ask him. The point is that these are normally very reliable pumps. The majority of marine engines use rubber impeller pumps and I would bet that the majority of them use this type of seal. I've never thought about this but I would think that the seals need to be changed about every fourth impeller change. Maybe not even that often.
Unless you are running the boat a hell of a lot, the seals on this pump would normally last longer than "a few months".

[delmarrey]

Actually, pumps that sit for long periods will leak more often then those with continuous work. The seals and springs rely on the vibration/motion/heat to keep them seated and grit free.

If bearings are bad they'll most likely be making noise, especially if water has gotten into them. A rusty bearing will only last for a few hours. Being a double row bearing'd shaft, there should be NO side play at all.

[sdowney717]

the bearings are tight no side play.
to me these pumps would be just fine if they would not leak so often.

I feel like I describe exactly how these seals work and what happens and people dont understand. Over the years when the pumps start leaking and I pull out the seal, the carbon face is always stuck. If you take a new one and press on it with your finger you will feel it move and spring back.

perhaps an acid dip vinegar etc... would clean them out.

[sdowney717]

update, the pump is no longer leaking.
I took the whole thing apart.
took the old seal, washed with dish soap and soaked in vinegar a few hours.
It was moving better then, the black carbon plastic inside the brass housing.
Still not great like when new. But movement and springy is a good thing.
Rinsed. blew and dried with compressed air.
I then took some wheel lithium grease and totally saturated the inside as much as I could. In the future I will use a hyperdermic, you can inject in the space between housing and black carbon.
Put the grease on the bronze pump seal bore.
Carefully drove in the seal. I have a wood dowel I machined to fit with a center pin for this. Drive this down in the bore so that when you put in the bearing shaft with the white ceramic seal it will push this bronze black seal backwards.
Greased up the white ceramic seal, shaft seals bearing, etc...
Carelessly wiped off any grease from the seal surface.

And it does not leak at all when it runs.
I hope the lithium grease will repel enough water that it lasts.

In the past I would use a thin smear of non hardening sealer like permatek number 2 on the bronze seal bore to seal bronze pump bore to bronze seal body. This time I used only the lithium grease in a cartridge, like you buy at Wal-mart.

[delmarrey]

WTG - Glad it worked out for ya!

Like I said in the my last post, run it once in a while. Or, if your going to just let it sit, flush out the raw water system with fresh water and antifreeze.

[vintageray]

I took the cover off mine today to change the impeller. The old impeller looks better than the new ones (spares) that are in their boxes. Greased it up a little and stuck it back in. Mine is gear driven, attached behind the timing cover on the old Perkins 4.236. Looks like a hunk of rust, but doesn't leak (fingers crossed). Last replaced in April 1995 at a cost of $438.00 for the pump. Ya' all are making me nervous.

[sdowney717]

be careful with oil or grease on neoprene impellors which can cause them to swell. Nitile does not swell up.

best to use a little dish soap.

[Shanaly]

Originally Posted by 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?

hello HopCar, you may be able to help me....! I have a Ford Lees 2701E, the 'jabsco' pump has a lip seal on the 3/4in shaft as it entered the impeller housing. jabsco no longer offers it. it sounds like you understand seals, can you suggest one....?

[delmarrey]

Originally Posted by Shanaly

hello HopCar, you may be able to help me....! I have a Ford Lees 2701E, the 'jabsco' pump has a lip seal on the 3/4in shaft as it entered the impeller housing. jabsco no longer offers it. it sounds like you understand seals, can you suggest one....?

http://www.timken.com/en-us/products...nfoSection.pdf

[shakey doug]

G,day,
Any industral bearing & transmission supplier will be able to supply a replacement. Either take a sample along or give them the OD-ID & width, to convert it suitable for marine use remove the inner steel expander ring and replace it with a neoprene O ring.