Anyone familiar with dismantling a Jabsco 3270?

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NealB

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Having cut an access panel in the bulkhead, I've now succeeded in removing my leaky raw water pump, ready to fit new seals.

I've taken out the impellor, and removed the cam.

Does anyone know how I remove the shaft, to get access to the seals?

The following drawing shows a 'wear plate':

http://www.marinepartsexpress.com/jabsco_fs.html

Looking closely at mine, I'd swear I'm looking straight at the bottom of the pump cavity (ie no wear plate), but I could be wrong. I've very gingerly tried prising the bottom with circlip pliers, but there is no sign of movement.

Any tips gratefully received, as I'm very nervous of scoring the inside surfaces.

Thanks.
 
Sorry if this is an obvious question but have you removed the entire pump from the engine? There are two seals, an oil seal at the rear and a water seal at the front (behind the impellor)

John
 
Not done one exaclty like this but the shaft should knock out from the engine side then you can knock out the bearings followed by the seals and wear plate if there is one. Then prise that O ring out of its groove.

Take care not to damage the new seals when refitting the shaft.
 
Check this website

http://www.depcopump.com/datajabsco.htm

If you scroll down you will find two version of the 3270 pump.

It also gives some information about removing from a Perkins which you should have a read at.

You may need to make up some form of drift to remove the shaft and the bearings as most Jabscos I have worked on have the bearing shrunk in.

John
 
As Vic said, take care not to damage the seals when refitting. I cover the splines with a selotape, that way you wont cut the seals on the sharp edges.

Might have misread your note to Vic but I think you may be planning to "wack" the shaft the wrong way.

John
 
Thanks for the link. Very informative.

Yes, I realised the conflict between Vic's advice and my response a few minutes after I'd written it.

The original (1966) engine handbook states that the shaft is "withdrawn rearwards from the pump body". Maybe a different pump has been fitted over the years.

The book makes it sound like a 10 minute job.
 
[ QUOTE ]
So I just put the pump in a vice and whack the outer end of the shaft (protecting the splines with a bit of wood

[/ QUOTE ] No the other way from the engine side towards the water side.

Best idea may be to support the pump on some blocks of wood water side down and tap the shaft through like that. Don't like the idea of trying to grip it in a vice, recipe for doing damage. Be very careful of the face that the cover bolts on to.

'S going to make things difficult if the bearings are "shrunk" in but if they are heating it all in some nearly boiling water (I assume its a brass or bronze body) should make things easier.
Make sure when you drift out the bearings you only hit the outer race and do it evenly. Tap one side then the other then at 90 degs to keep it square all the way.
Just like you do with wheel bearings.
 
Slight difference of opinion here. My reading of the instructions is that you drift it out from the impellor end. The danger of drifting out from the engine end is that you may damage the dog. Mind you I hardly ever read manuals so i may have got it wrong.

John
 
Huge thanks for your time, to both Vic and John.

Tomorrow, I'll try some tentative tapping of the shaft, as Vic suggests, to see if it moves. If it doesn't move, I think I'll loose my nerve and take it round to the local mechanic. At least I'll have saved removal and refitting costs.

Thanks again.
 
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