Leaking Jabsco water pump

Fascadale

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I have this pump on my engine

DSCF0682_zpsb60d3494.jpg


I took it off the engine during the winter so that I could drill out the broken screw.

After it went back on the engine the impeller was replaced, it got a new cover gasket and new screws.

There is now a drip, not fast but not slow coming from the rear of the impeller casing.

It not leaking from either the inlet or outlet and its not leaking from around the cover.

(Why do things get worse after you fix things?)

Suggestions please!
 
I have this pump on my engine



I took it off the engine during the winter so that I could drill out the broken screw.

After it went back on the engine the impeller was replaced, it got a new cover gasket and new screws.

There is now a drip, not fast but not slow coming from the rear of the impeller casing.

It not leaking from either the inlet or outlet and its not leaking from around the cover.

(Why do things get worse after you fix things?)

Suggestions please!

It's the seal. Water escapes from weephole. It won't heal itself

Take off again

Might as well replace the oil seal as well

But check the shaft for wear and check the bearings.
 
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Seals are easy to replace. It depends where the water goes and how much of a pain it is to you - it may be minute in comparison to the shaft log drip for instance.
The pump is designed to spin out any leaks before they damage the bearings or get into the timing gears, as long as the drain holes are clear.
Hopefully it's the seal rather than the £60 shaft that's the problem. I assume there is not an alignment procedure (like on Perk4108s) that you failed to observe during re-installation.
 
Did the shaft come out with the impeller? This can disturb the seals make sure the oil seals hav ss springs and go back in the correct way back to bck with springs facing!
 
Worth replacing the cover with a Speedseal when you have done the job. Does away with those silly little screws.
 
Thanks for all the advice.

I have just done this. Most awkward thing was working out the order of replacing the parts on the shaft since you have to use a press of some sort to get the old out and new bearings in. Also, make sure you measure locations on the shafts of the bearings since I found they moved a bit when I was bringing the shaft out of the pump. A rear bearing acting as a cam (for the fuel pump on my vetus) caused these difficulties, and probably won't be there on most other engines.

An afterthought - my shaft was slightly worn where the seals were but replacement was no longer available. I just used the old shaft and it seems fine with no drips/
 
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I have this pump on my engine

DSCF0682_zpsb60d3494.jpg


I took it off the engine during the winter so that I could drill out the broken screw.

After it went back on the engine the impeller was replaced, it got a new cover gasket and new screws.

There is now a drip, not fast but not slow coming from the rear of the impeller casing.

It not leaking from either the inlet or outlet and its not leaking from around the cover.

(Why do things get worse after you fix things?)

Suggestions please!

You'll probably find some pitting on the shaft when you take it out. You may get lucky with new seals but a speedi sleeve will solve the problem at about a third of the cost. If you do opt to replace the pump and keep that one as a spare the Jabsco replacement is much better designed with an o ring on the impeller housing and 3 No. 10mm bolts (I'm guessing from what I can see that's it a BD722??) Either way its worth comparing the cost of a speedi sleeve, new shaft and replacement pump if the seals only solution doesn't work.
 
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